PageSourceSearch
Opt out API access

https://bunfig.netlify.app/assets/migration.md.Cli5yz4A.js

js bunfig.netlify.app collected 2026-10-03 10:32:44 UTC 126,764 bytes, 455 lines download raw bytes 

1import{_ as i,o as a,i as n,ak as h}from"./chunks/framework.CIfHljvi.js";const d=JSON.parse('{"title":"Migration Guide","description":"","frontmatter":{},"headers":[],"relativePath":"migration.md","filePath":"migration.md","lastUpdated":1758421350000}'),l={name:"migration.md"};function t(p,s,k,e,r,E){return a(),n("div",null,[...s[0]||(s[0]=[h(`<h1 id="migration-guide" tabindex="-1">Migration Guide <a class="header-anchor" href="#migration-guide" aria-label="Permalink to &quot;Migration Guide&quot;">​</a></h1><p>This guide helps you migrate from other configuration libraries to bunfig, providing step-by-step instructions and code examples for common migration scenarios.</p><h2 id="from-dotenv" tabindex="-1">From dotenv <a class="header-anchor" href="#from-dotenv" aria-label="Permalink to &quot;From dotenv&quot;">​</a></h2><p>If you&#39;re using dotenv (<code>.env</code> files), bunfig can automatically read environment variables and merge them with your configuration.</p><h3 id="before-dotenv" tabindex="-1">Before (dotenv) <a class="header-anchor" href="#before-dotenv" aria-label="Permalink to &quot;Before (dotenv)&quot;">​</a></h3><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// .env file content</span></span>
2<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// PORT=3000</span></span>
3<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// HOST=localhost</span></span>
4<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// DATABASE_URL=postgresql://localhost:5432/myapp</span></span>
5<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// REDIS_URL=redis://localhost:6379</span></span>
6<span class="line"></span>
7<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.js</span></span>
8<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;dotenv&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">).</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">()</span></span>
9<span class="line"></span>
10<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
11<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
12<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">HOST</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
13<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
14<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;postgresql://localhost:5432/default&#39;</span></span>
15<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
16<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  redis: {</span></span>
17<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">REDIS_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;redis://localhost:6379&#39;</span></span>
18<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
19<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><h3 id="after-bunfig" tabindex="-1">After (bunfig) <a class="header-anchor" href="#after-bunfig" aria-label="Permalink to &quot;After (bunfig)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

19<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.config.ts</span></span>
20<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.ts</span></span>
21<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
22<span class="line"></span>
23<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
24<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
25<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
26<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
27<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;postgresql://localhost:5432/myapp&#39;</span></span>
28<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
29<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  redis: {</span></span>
30<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;redis://localhost:6379&#39;</span></span>
31<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
32<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
33<span class="line"></span>
34<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
35<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
36<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">  // Environment variables automatically override config values</span></span>
37<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">  // APP_PORT, APP_HOST, APP_DATABASE_URL, APP_REDIS_URL</span></span>
38<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><p><strong>Migration Benefits:</strong></p><ul><li>✅ Automatic environment variable detection</li><li>✅ Type safety with TypeScript</li><li>✅ No manual <code>process.env</code> parsing</li><li>✅ Built-in validation and error handling</li><li>✅ Multiple configuration sources (files, env vars, package.json)</li></ul><h2 id="from-node-config" tabindex="-1">From node-config <a class="header-anchor" href="#from-node-config" aria-label="Permalink to &quot;From node-config&quot;">​</a></h2><p>The <code>config</code> npm package uses directory-based configuration files.</p><h3 id="before-node-config" tabindex="-1">Before (node-config) <a class="header-anchor" href="#before-node-config" aria-label="Permalink to &quot;Before (node-config)&quot;">​</a></h3><div class="language-json vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">json</span>

38<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// config/default.json</span></span>
39<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">{</span></span>
40<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;server&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
41<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
42<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;localhost&quot;</span></span>
43<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
44<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;database&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
45<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;localhost&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
46<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">5432</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
47<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;name&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;myapp&quot;</span></span>
48<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
49<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-json vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">json</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// config/production.json</span></span>
50<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">{</span></span>
51<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;server&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
52<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">8080</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
53<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;0.0.0.0&quot;</span></span>
54<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
55<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;database&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
56<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;prod-db.example.com&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
57<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;ssl&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">true</span></span>
58<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
59<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span>

59<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.js</span></span>
60<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;config&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
61<span class="line"></span>
62<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> server</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> config.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">

62get</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;server&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
63<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> database</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> config.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">get</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;database&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span></code></pre></div><h3 id="after-bunfig-1" tabindex="-1">After (bunfig) <a class="header-anchor" href="#after-bunfig-1" aria-label="Permalink to &quot;After (bunfig)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.ts</span></span>
64<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
65<span class="line"></span>
66<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// config/base.config.ts</span></span>
67<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// config/production.config.ts</span></span>
68<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> base </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;./base.config&#39;</span></span>
69<span class="line"></span>
70<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
71<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  server: {</span></span>
72<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
73<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span></span>
74<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
75<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
76<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
77<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">5432</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
78<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;myapp&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
79<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">

79    ssl: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">false</span></span>
80<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
81<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
82<span class="line"></span>
83<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
84<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  ...</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">base,</span></span>
85<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  server: {</span></span>
86<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    ...</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">base.server,</span></span>
87<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">8080</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
88<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;0.0.0.0&#39;</span></span>
89<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
90<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
91<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    ...</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">base.database,</span></span>
92<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;prod-db.example.com&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
93<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    ssl: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">true</span></span>
94<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
95<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
96<span class="line"></span>
97<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> environment</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">NODE_ENV</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;base&#39;</span></span>
98<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
99<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: environment,</span></span>
100<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  cwd: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;./config&#39;</span></span>
101<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><p><strong>Migration Benefits:</strong></p><ul><li>✅ Better TypeScript support</li><li>✅ More flexible file formats (TS, JS, JSON)</li><li>✅ Built-in environment variable integration</li><li>✅ Validation and error handling</li><li>✅ Home directory configuration support</li></ul><h2 id="from-rc-files" tabindex="-1">From rc files <a class="header-anchor" href="#from-rc-files" aria-label="Permalink to &quot;From rc files&quot;">​</a></h2><p>RC configuration libraries use dotfiles with JSON configuration.</p><h3 id="before-rc" tabindex="-1">Before (rc) <a class="header-anchor" href="#before-rc" aria-label="Permalink to &quot;Before (rc)&quot;">​</a></h3><div class="language-json vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">json</span>

101<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">{</span></span>
102<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
103<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;localhost&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
104<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;database&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
105<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;url&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;postgresql://localhost:5432/myapp&quot;</span></span>
106<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
107<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.js</span></span>
108<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> rc</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;rc&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
109<span class="line"></span>
110<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Load config with defaults</span></span>
111<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> rcResult</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> rc</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;myapp&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, {</span></span>
112<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
113<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
114<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
115<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;postgresql://localhost:5432/default&#39;</span></span>
116<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
117<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><h3 id="after-bunfig-2" tabindex="-1">After (bunfig) <a class="header-anchor" href="#after-bunfig-2" aria-label="Permalink to &quot;After (bunfig)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

117<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// .myapp.config.ts</span></span>
118<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
119<span class="line"></span>
120<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
121<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
122<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
123<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
124<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;postgresql://localhost:5432/myapp&#39;</span></span>
125<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
126<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
127<span class="line"></span>
128<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
129<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;myapp&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
130<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  defaultConfig: {</span></span>
131<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
132<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
133<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    database: {</span></span>
134<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;postgresql://localhost:5432/default&#39;</span></span>
135<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    }</span></span>
136<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
137<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><p><strong>Migration Benefits:</strong></p><ul><li>✅ TypeScript support for better development experience</li><li>✅ More file format options</li><li>✅ Better error handling and validation</li><li>✅ Environment variable integration</li><li>✅ Package.json integration</li></ul><h2 id="from-cosmiconfig" tabindex="-1">From Cosmiconfig <a class="header-anchor" href="#from-cosmiconfig" aria-label="Permalink to &quot;From Cosmiconfig&quot;">​</a></h2><p>Cosmiconfig searches for configuration files in various formats.</p><h3 id="before-cosmiconfig" tabindex="-1">Before (cosmiconfig) <a class="header-anchor" href="#before-cosmiconfig" aria-label="Permalink to &quot;Before (cosmiconfig)&quot;">​</a></h3><div class="language-json vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">json</span>

137<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// package.json</span></span>
138<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">{</span></span>
139<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;name&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;my-project&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
140<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;version&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;1.0.0&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
141<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;myapp&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: {</span></span>
142<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
143<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;localhost&quot;</span></span>
144<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
145<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-json vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">json</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// .myapprc.json</span></span>
146<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">{</span></span>
147<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;port&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
148<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  &quot;host&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;localhost&quot;</span></span>
149<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// myapp.config.js</span></span>
150<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">module</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">exports</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
151<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
152<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span></span>
153<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span>

153<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.js</span></span>
154<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">cosmiconfigSync</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;cosmiconfig&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
155<span class="line"></span>
156<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> explorer</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> cosmiconfigSync</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;myapp&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
157<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> result</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> explorer.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">search</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">()</span></span>
158<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> result </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">?</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> result.config </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {}</span></span></code></pre></div><h3 id="after-bunfig-3" tabindex="-1">After (bunfig) <a class="header-anchor" href="#after-bunfig-3" aria-label="Permalink to &quot;After (bunfig)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Any of these work automatically:</span></span>
159<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// - myapp.config.ts</span></span>
160<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// - .myapp.config.ts</span></span>
161<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// - myapp.config.js</span></span>
162<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// - package.json (with &quot;myapp&quot; field)</span></span>
163<span class="line"></span>
164<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// myapp.config.ts</span></span>
165<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.ts</span></span>
166<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
167<span class="line"></span>
168<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
169<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
170<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span></span>
171<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
172<span class="line"></span>
173<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;myapp&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span></code></pre></div><p><strong>Migration Benefits:</strong></p><ul><li>

173✅ Built-in support for all common file locations</li><li>✅ TypeScript and modern ES modules</li><li>✅ Environment variable integration</li><li>✅ Validation and error handling</li><li>✅ Better performance with caching</li></ul><h2 id="from-environment-variables-only" tabindex="-1">From Environment Variables Only <a class="header-anchor" href="#from-environment-variables-only" aria-label="Permalink to &quot;From Environment Variables Only&quot;">​</a></h2><p>If you&#39;re only using environment variables, bunfig makes it easier to organize and validate them.</p><h3 id="before-environment-variables" tabindex="-1">Before (environment variables) <a class="header-anchor" href="#before-environment-variables" aria-label="Permalink to &quot;Before (environment variables)&quot;">​</a></h3><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.js</span></span>
174<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
175<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  server: {</span></span>
176<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">parseInt</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">PORT</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
177<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">HOST</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;localhost&#39;</span></span>
178<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
179<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
180<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;postgresql://localhost:5432/default&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
181<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    pool: Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">parseInt</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">DB_POOL</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
182<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    ssl: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">DB_SSL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ===</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;true&#39;</span></span>
183<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
184<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  redis: {</span></span>
185<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">REDIS_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;redis://localhost:6379&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
186<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    db: Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">parseInt</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">REDIS_DB</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 0</span></span>
187<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
188<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  features: {</span></span>
189<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    enableCache: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">ENABLE_CACHE</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ===</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;true&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
190<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    enableMetrics: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">ENABLE_METRICS</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ===</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;true&#39;</span></span>
191<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
192<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
193<span class="line"></span>
194<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Manual validation</span></span>
195<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">if</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">!</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">config.database.url) {</span></span>
196<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  throw</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> Error</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;DATABASE_URL is required&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
197<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
198<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">if</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (config.server.port </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">&lt;</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 1</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> config.server.port </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">&gt;</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 65535</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) {</span></span>
199<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  throw</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> Error</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;PORT must be between 1 and 65535&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
200<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span></code></pre></div><h3 id="after-bunfig-4" tabindex="-1">After (bunfig) <a class="header-anchor" href="#after-bunfig-4" aria-label="Permalink to &quot;After (bunfig)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

200<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.config.ts</span></span>
201<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// app.ts</span></span>
202<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
203<span class="line"></span>
204<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
205<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  server: {</span></span>
206<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
207<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    host: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;localhost&#39;</span></span>
208<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
209<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database: {</span></span>
210<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;postgresql://localhost:5432/default&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
211<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    pool: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">5</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
212<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    ssl: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">false</span></span>
213<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
214<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  redis: {</span></span>
215<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    url: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;redis://localhost:6379&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
216<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    db: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">0</span></span>
217<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  },</span></span>
218<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  features: {</span></span>
219<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    enableCache: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">false</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
220<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    enableMetrics: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">false</span></span>
221<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
222<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
223<span class="line"></span>
224<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">

224({</span></span>
225<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
226<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  schema: {</span></span>
227<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
228<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    properties: {</span></span>
229<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      server: {</span></span>
230<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
231<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        properties: {</span></span>
232<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">          port: { type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;number&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, minimum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">1</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, maximum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">65535</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> },</span></span>
233<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">          host: { type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;string&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, minLength: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">1</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> }</span></span>
234<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        },</span></span>
235<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        required: [</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;port&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;host&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span>
236<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      },</span></span>
237<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      database: {</span></span>
238<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
239<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        properties: {</span></span>
240<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">          url: { type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;string&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, pattern: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;^postgresql://&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> },</span></span>
241<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">          pool: { type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;number&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, minimum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">1</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, maximum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">100</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> }</span></span>
242<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        },</span></span>
243<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        required: [</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;url&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span>
244<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      }</span></span>
245<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    },</span></span>
246<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    required: [</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;server&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;database&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span>
247<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
248<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span>
249<span class="line"></span>
250<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Environment variables automatically override:</span></span>
251<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// APP_SERVER_PORT=8080</span></span>
252<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// APP_DATABASE_URL=postgresql://prod:5432/app</span></span>
253<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// APP_FEATURES_ENABLECACHE=true</span></span></code></pre></div><p><strong>Migration Benefits:</strong></p><ul><li>✅ Automatic type conversion (string → number, string → boolean)</li><li>✅ Built-in validation with JSON Schema</li><li>✅ Default values in configuration files</li><li>✅ Better error messages for invalid values</li><li>

253✅ No manual parsing or validation code</li></ul><h2 id="migration-checklist" tabindex="-1">Migration Checklist <a class="header-anchor" href="#migration-checklist" aria-label="Permalink to &quot;Migration Checklist&quot;">​</a></h2><h3 id="step-1-install-bunfig" tabindex="-1">Step 1: Install bunfig <a class="header-anchor" href="#step-1-install-bunfig" aria-label="Permalink to &quot;Step 1: Install bunfig&quot;">​</a></h3><div class="language-bash vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">bash</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Remove old dependencies</span></span>
254<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">bun</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> remove</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> dotenv</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> config</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> rc</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> cosmiconfig</span></span>
255<span class="line"></span>
256<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Install bunfig</span></span>
257<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">bun</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> add</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> bunfig</span></span></code></pre></div><h3 id="step-2-create-configuration-files" tabindex="-1">Step 2: Create Configuration Files <a class="header-anchor" href="#step-2-create-configuration-files" aria-label="Permalink to &quot;Step 2: Create Configuration Files&quot;">​</a></h3><div class="language-bash vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">bash</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Create your first config file</span></span>
258<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">touch</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> app.config.ts</span></span>
259<span class="line"></span>
260<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Or organize by feature</span></span>
261<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">mkdir</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> config</span></span>
262<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">touch</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> config/server.config.ts</span></span>
263<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">touch</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> config/database.config.ts</span></span></code></pre></div><h3 id="step-3-convert-configuration" tabindex="-1">Step 3: Convert Configuration <a class="header-anchor" href="#step-3-convert-configuration" aria-label="Permalink to &quot;Step 3: Convert Configuration&quot;">​</a></h3><ol><li><strong>Extract defaults</strong> from your code into configuration files</li><li><strong>Remove manual environment variable parsing</strong></li><li><strong>Add TypeScript interfaces</strong> for type safety</li><li><strong>Add validation schemas</strong> for critical settings</li></ol><h3 id="step-4-update-application-code" tabindex="-1">Step 4: Update Application Code <a class="header-anchor" href="#step-4-update-application-code" aria-label="Permalink to &quot;Step 4: Update Application Code&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

263<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Before</span></span>
264<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// After</span></span>
265<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
266<span class="line"></span>
267<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;config&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
268<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> port</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> config.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">

268get</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;server.port&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
269<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">server</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
270<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> port</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> server.port </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Already includes env var overrides</span></span></code></pre></div><h3 id="step-5-update-environment-variables" tabindex="-1">Step 5: Update Environment Variables <a class="header-anchor" href="#step-5-update-environment-variables" aria-label="Permalink to &quot;Step 5: Update Environment Variables&quot;">​</a></h3><div class="language-bash vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">bash</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Before (dotenv style)</span></span>
271<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">3000</span></span>
272<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">postgresql://localhost:5432/app</span></span>
273<span class="line"></span>
274<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># After (bunfig style with prefixes)</span></span>
275<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">APP_SERVER_PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">3000</span></span>
276<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">APP_DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">postgresql://localhost:5432/app</span></span></code></pre></div><h3 id="step-6-add-validation-optional" tabindex="-1">Step 6: Add Validation (Optional) <a class="header-anchor" href="#step-6-add-validation-optional" aria-label="Permalink to &quot;Step 6: Add Validation (Optional)&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">

276({</span></span>
277<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
278<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  schema: {</span></span>
279<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
280<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    properties: {</span></span>
281<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      server: {</span></span>
282<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
283<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        properties: {</span></span>
284<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">          port: { type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;number&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, minimum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">1</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, maximum: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">65535</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> }</span></span>
285<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        },</span></span>
286<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">        required: [</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;port&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span>
287<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">      }</span></span>
288<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    }</span></span>
289<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
290<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><h3 id="step-7-test-migration" tabindex="-1">Step 7: Test Migration <a class="header-anchor" href="#step-7-test-migration" aria-label="Permalink to &quot;Step 7: Test Migration&quot;">​</a></h3><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Create a test to verify migration</span></span>
291<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { describe, expect, it } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bun:test&#39;</span></span>
292<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { config } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;bunfig&#39;</span></span>
293<span class="line"></span>
294<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">describe</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;Configuration Migration&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">

294, () </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
295<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">  it</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;should load configuration with defaults&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">async</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> () </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
296<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> cfg</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
297<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">    expect</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(cfg.server.port).</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">toBe</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
298<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">    expect</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(cfg.database.url).</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">toBeDefined</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">()</span></span>
299<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  })</span></span>
300<span class="line"></span>
301<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">  it</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;should override with environment variables&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">async</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> () </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
302<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">APP_SERVER_PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;8080&#39;</span></span>
303<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> cfg</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
304<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">    expect</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(cfg.server.port).</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">toBe</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">8080</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
305<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    delete</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">APP_SERVER_PORT</span></span>
306<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  })</span></span>
307<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><h2 id="common-migration-issues" tabindex="-1">Common Migration Issues <a class="header-anchor" href="#common-migration-issues" aria-label="Permalink to &quot;Common Migration Issues&quot;">​</a></h2><h3 id="environment-variable-naming" tabindex="-1">Environment Variable Naming <a class="header-anchor" href="#environment-variable-naming" aria-label="Permalink to &quot;Environment Variable Naming&quot;">​</a></h3><p><strong>Issue:</strong> Environment variables not being picked up.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

307<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ❌ Wrong: dotenv style variables</span></span>
308<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;3000&#39;</span></span>
309<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;postgresql://...&#39;</span></span>
310<span class="line"></span>
311<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ✅ Correct: bunfig requires prefixed variables</span></span>
312<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">APP_SERVER_PORT</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;3000&#39;</span></span>
313<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">APP_DATABASE_URL</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;postgresql://...&#39;</span></span></code></pre></div><h3 id="nested-configuration" tabindex="-1">Nested Configuration <a class="header-anchor" href="#nested-configuration" aria-label="Permalink to &quot;Nested Configuration&quot;">​</a></h3><p><strong>Issue:</strong> Complex nested configurations not working.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ❌ Wrong: flat environment variables</span></span>
314<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">SERVER_DATABASE_POOL_SIZE</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;10&#39;</span></span>
315<span class="line"></span>
316<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ✅ Correct: use underscores for nesting</span></span>
317<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">APP_DATABASE_POOL_SIZE</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;10&#39;</span></span>
318<span class="line"></span>
319<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Which maps to:</span></span>
320<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// {</span></span>
321<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">//   database: {</span></span>
322<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">//     pool: {</span></span>
323<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">//       size: 10</span></span>
324<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">//     }</span></span>
325<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">//   }</span></span>
326<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// }</span></span></code></pre></div><h3 id="type-conversion" tabindex="-1">Type Conversion <a class="header-anchor" href="#type-conversion" aria-label="Permalink to &quot;Type Conversion&quot;">​</a></h3><p><strong>Issue:</strong> Environment variables staying as strings.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

326<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ❌ Manual conversion needed before</span></span>
327<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> port</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">parseInt</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">PORT</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 3000</span></span>
328<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> enabled</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">ENABLE_FEATURE</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ===</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;true&#39;</span></span>
329<span class="line"></span>
330<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ✅ Automatic conversion with bunfig</span></span>
331<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Set defaults with correct types in config file:</span></span>
332<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
333<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  port: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">3000</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// number type</span></span>
334<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  enabled: </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">false</span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // boolean type</span></span>
335<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
336<span class="line"></span>
337<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Environment variables automatically converted:</span></span>
338<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// APP_PORT=8080 → port: 8080 (number)</span></span>
339<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// APP_ENABLED=true → enabled: true (boolean)</span></span></code></pre></div><h3 id="file-locations" tabindex="-1">File Locations <a class="header-anchor" href="#file-locations" aria-label="Permalink to &quot;File Locations&quot;">​</a></h3><p><strong>Issue:</strong> Configuration files not found.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ❌ Wrong: files in wrong location or wrong name</span></span>
340<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// These files won&#39;t be detected by bunfig:</span></span>
341<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// config/default.json</span></span>
342<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// .env</span></span>
343<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// .myapprc</span></span>
344<span class="line"></span>
345<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// ✅ Correct: bunfig file patterns</span></span>
346<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> correctPatterns</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> [</span></span>
347<span class="line"><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">  &#39;app.config.ts&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Primary</span></span>
348<span class="line"><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">  &#39;.app.config.ts&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Alternative</span></span>
349<span class="line"><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">  &#39;config/app.config.ts&#39;</span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // In subdirectory</span></span>
350<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span></code></pre></div><h2 id="advanced-migration-patterns" tabindex="-1">Advanced Migration Patterns <a class="header-anchor" href="#advanced-migration-patterns" aria-label="Permalink to &quot;Advanced Migration Patterns&quot;">​</a></h2><h3 id="gradual-migration" tabindex="-1">Gradual Migration <a class="header-anchor" href="#gradual-migration" aria-label="Permalink to &quot;Gradual Migration&quot;">​</a></h3><p>Migrate piece by piece instead of all at once:</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

350<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 1: Keep existing config, add bunfig for new features</span></span>
351<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> legacyConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;config&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
352<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> newFeatures</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;features&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
353<span class="line"></span>
354<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> combinedConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
355<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  ...</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">legacyConfig,</span></span>
356<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  features: newFeatures</span></span>
357<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
358<span class="line"></span>
359<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 2: Migrate critical services</span></span>
360<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> database</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;database&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
361<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> combinedConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
362<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  ...</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">legacyConfig,</span></span>
363<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  database,</span></span>
364<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  features: newFeatures</span></span>
365<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">}</span></span>
366<span class="line"></span>
367<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 3: Complete migration</span></span>
368<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span></code></pre></div><h3 id="configuration-validation-migration" tabindex="-1">Configuration Validation Migration <a class="header-anchor" href="#configuration-validation-migration" aria-label="Permalink to &quot;Configuration Validation Migration&quot;">​</a></h3><p>Add validation gradually:</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

368<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 1: Basic loading without validation</span></span>
369<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> loadConfig</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({ name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> })</span></span>
370<span class="line"></span>
371<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 2: Add basic validation</span></span>
372<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> loadConfig</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
373<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
374<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  schema: {</span></span>
375<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    type: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;object&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
376<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">    required: [</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;server&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;database&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">]</span></span>
377<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  }</span></span>
378<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span>
379<span class="line"></span>
380<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Phase 3: Comprehensive validation</span></span>
381<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> loadConfig</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
382<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
383<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  schema: detailedSchema,</span></span>
384<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  validate: customValidationFunction</span></span>
385<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><h3 id="environment-strategy-migration" tabindex="-1">Environment Strategy Migration <a class="header-anchor" href="#environment-strategy-migration" aria-label="Permalink to &quot;Environment Strategy Migration&quot;">​</a></h3><p>Transition environment strategies:</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span>

385<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Before: Manual environment detection</span></span>
386<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> environment</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">NODE_ENV</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;development&#39;</span></span>
387<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> configFile</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> \`config/\${</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">environment</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">}.json\`</span></span>
388<span class="line"></span>
389<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// During migration: Support both</span></span>
390<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> legacyConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(configFile)</span></span>
391<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> bunfigConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
392<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: environment,</span></span>
393<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  cwd: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;./config&#39;</span></span>
394<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span>
395<span class="line"></span>
396<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// After migration: Pure bunfig</span></span>
397<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> appConfig</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> await</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> config</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">({</span></span>
398<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: process.env.</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">NODE_ENV</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &#39;development&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
399<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  cwd: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;./config&#39;</span></span>
400<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span></code></pre></div><h2 id="migration-tools" tabindex="-1">Migration Tools <a class="header-anchor" href="#migration-tools" aria-label="Permalink to &quot;Migration Tools&quot;">​</a></h2><h3 id="automated-migration-script" tabindex="-1">Automated Migration Script <a class="header-anchor" href="#automated-migration-script" aria-label="Permalink to &quot;Automated Migration Script&quot;">​</a></h3><div class="language-bash vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">bash</span>

400<pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">#!/bin/bash</span></span>
401<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># migrate-to-bunfig.sh</span></span>
402<span class="line"></span>
403<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;🔄 Migrating to bunfig...&quot;</span></span>
404<span class="line"></span>
405<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Backup existing configuration</span></span>
406<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">mkdir</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> -p</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> migration-backup</span></span>
407<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">cp</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> -r</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> config</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> migration-backup/</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> 2&gt;</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">/dev/null</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> true</span></span>
408<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">cp</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> .env</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">*</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> migration-backup/</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> 2&gt;</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">/dev/null</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> ||</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> true</span></span>
409<span class="line"></span>
410<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Install bunfig</span></span>
411<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;📦 Installing bunfig...&quot;</span></span>
412<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">bun</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> add</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> bunfig</span></span>
413<span class="line"></span>
414<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Convert .env to config file</span></span>
415<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">if</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> [ </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">-f</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> .env ]; </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">then</span></span>
416<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">  echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;🔧 Converting .env to app.config.ts...&quot;</span></span>
417<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">

417  node</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> migration-scripts/convert-env.js</span></span>
418<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">fi</span></span>
419<span class="line"></span>
420<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"># Convert rc files</span></span>
421<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> file </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">in</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> .*rc</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">; </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">do</span></span>
422<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  if</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> [ </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">-f</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$file</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> ]; </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">then</span></span>
423<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">    echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;🔧 Converting </span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$file</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">...&quot;</span></span>
424<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">    node</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> migration-scripts/convert-rc.js</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$file</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;</span></span>
425<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  fi</span></span>
426<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">done</span></span>
427<span class="line"></span>
428<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;✅ Migration complete! Check your new configuration files.&quot;</span></span>
429<span class="line"><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">echo</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;🧪 Run tests to verify the migration.&quot;</span></span></code></pre></div><h3 id="environment-variable-converter" tabindex="-1">Environment Variable Converter <a class="header-anchor" href="#environment-variable-converter" aria-label="Permalink to &quot;Environment Variable Converter&quot;">​</a></h3><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code" style="--shiki-light:#24292e;--shiki-dark:#e1e4e8;--shiki-light-bg:#fff;--shiki-dark-bg:#24292e;" tabindex="0"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// migration-scripts/convert-env.js</span></span>
430<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> fs</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> require</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;node:fs&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
431<span class="line"></span>
432<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Read .env file</span></span>
433<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> envContent</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> fs.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">readFileSync</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;.env&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;utf8&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
434<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> envVars</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> envContent</span></span>
435<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  .</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">split</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">\\n</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
436<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  .</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">filter</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">line</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> line.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">trim</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">() </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">&amp;&amp;</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> !</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">line.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">startsWith</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;#&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">))</span></span>
437<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  .</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">map</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">((</span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">line</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
438<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    const</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> [</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">key</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">value</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">] </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> line.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">split</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;=&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span>
439<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">    return</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { key: key.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">trim</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(), value: value.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">trim</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">() }</span></span>
440<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  })</span></span>
441<span class="line"></span>
442<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Convert to config structure</span></span>
443<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> config</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {}</span></span>
444<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">envVars.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">forEach</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(({ </span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">key</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">value</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> }) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
445<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">  // Convert PORT=3000 to { port: 3000 }</span></span>
446<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> configKey</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> key.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">toLowerCase</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">()</span></span>
447<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> configValue</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">isNaN</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(value) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">?</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> value </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> Number.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">parseInt</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(value)</span></span>
448<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  config[configKey] </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> configValue</span></span>
449<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">})</span></span>
450<span class="line"></span>
451<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Generate TypeScript config file</span></span>
452<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> configContent</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> \`export default \${</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">JSON</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">stringify</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">(</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">config</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">, </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">null</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">, </span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">2</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">)</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">}\`</span></span>
453<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">fs.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">writeFileSync</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;app.config.ts&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, configContent)</span></span>
454<span class="line"></span>
455<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">console.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">log</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&#39;✅ Converted .env to app.config.ts&#39;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span></span></code></pre></div><h2 id="getting-help" tabindex="-1">Getting Help <a class="header-anchor" href="#getting-help" aria-label="Permalink to &quot;Getting Help&quot;">​</a></h2><ul><li><strong><a href="./quick-start">Quick Start Guide</a></strong> - Get started with bunfig</li><li><strong><a href="./features/configuration-loading">Configuration Loading</a></strong> - Understand how bunfig loads configuration</li><li><strong><a href="./features/environment-variables">Environment Variables</a></strong> - Learn about environment variable integration</li><li><strong><a href="https://github.com/stacksjs/bunfig/issues" target="_blank" rel="noreferrer">GitHub Issues</a></strong> - Report migration issues or get help</li></ul><h2 id="community-examples" tabindex="-1">Community Examples <a class="header-anchor" href="#community-examples" aria-label="Permalink to &quot;Community Examples&quot;">​</a></h2><p>Check out these real-world migration examples from the community:</p><ul><li><a href="https://github.com/stacksjs/bunfig/tree/main/examples/express-migration" target="_blank" rel="noreferrer">Express.js app migration</a></li><li><a href="https://github.com/stacksjs/bunfig/tree/main/examples/nextjs-m

455igration" target="_blank" rel="noreferrer">Next.js app migration</a></li><li><a href="https://github.com/stacksjs/bunfig/tree/main/examples/microservices-migration" target="_blank" rel="noreferrer">Microservices migration</a></li></ul><p>Have a migration story to share? <a href="https://github.com/stacksjs/bunfig/blob/main/CONTRIBUTING.md" target="_blank" rel="noreferrer">Contribute your example</a> to help others!</p>`,97)])])}const o=i(l,[["render",t]]);export{d as __pageData,o as default};

Line numbers count LF bytes from the start of the resource, as the search results do. Vendor segments are library code the classifier recognised; they are stored but not indexed. Bytes are shown as Latin1 characters, one per byte.