File Types - BunDocumentation Index
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import my_toml from "./my_file" with { type: "toml" };
// or with dynamic imports
const { default: my_toml } = await import("./my_file", { with: { type: "toml" } });
Built-in loaders
js
JavaScript. Default for .cjs and .mjs.
Parses the code and applies a set of default transforms like dead-code elimination and tree shaking. Note that Bun does not attempt to down-convert syntax at the moment.
jsx
JavaScript + JSX.. Default for .js and .jsx.
Same as the js loader, but JSX syntax is supported. By default, JSX is down-converted to plain JavaScript; the details of how this is done depends on the jsx* compiler options in your tsconfig.json. Refer to the TypeScript documentation on JSX for more information.
ts
TypeScript loader. Default for .ts, .mts, and .cts.
Strips out all TypeScript syntax, then behaves identically to the js loader. Bun does not perform typechecking.
tsx
TypeScript + JSX loader. Default for .tsx. Transpiles both TypeScript and JSX to vanilla JavaScript.
json
JSON loader. Default for .json.
JSON files can be directly imported.
import pkg from "./package.json"; pkg.name; // => "my-package"During bundling, the parsed JSON is inlined into the bundle as a JavaScript object.
var pkg = {
name: "my-package",
// ... other fields
};
pkg.name;
If a .json file is passed as an entrypoint to the bundler, it will be converted to a .js module that export defaults the parsed object.
InputOutput{
"name": "John Doe",
"age": 35,
"email": "johndoe@example.com"
}
jsonc
JSON with Comments loader. Default for .jsonc.
JSONC (JSON with Comments) files can be directly imported. Bun will parse them, stripping out comments and trailing commas.
import config from "./config.jsonc"; console.log(config);During bundling, the parsed JSONC is inlined into the bundle as a JavaScript object, identical to the json loader.
var config = {
option: "value",
};
import config from "./bunfig.toml";
config.logLevel; // => "debug"
// via import attribute:
// import myCustomTOML from './my.config' with {type: "toml"};
During bundling, the parsed TOML is inlined into the bundle as a JavaScript object.
var config = {
logLevel: "debug",
// ...other fields
};
config.logLevel;
If a .toml file is passed as an entrypoint, it will be converted to a .js module that export defaults the parsed object.
InputOutputname = "John Doe" age = 35 email = "johndoe@example.com"yaml YAML loader. Default for .yaml and .yml. YAML files can be directly imported. Bun will parse them with its fast native YAML parser.
import config from "./config.yaml";
console.log(config);
// via import attribute:
import data from "./data.txt" with { type: "yaml" };
During bundling, the parsed YAML is inlined into the bundle as a JavaScript object.
var config = {
name: "my-app",
version: "1.0.0",
// ...other fields
};
If a .yaml or .yml file is passed as an entrypoint, it will be converted to a .js module that export defaults the parsed object.
InputOutputname: John Doe age: 35 email: johndoe@example.comjson5 JSON5 loader. Default for .json5. JSON5 files can be directly imported. Bun will parse them with its fast native JSON5 parser. JSON5 is a superset of JSON that supports comments, trailing commas, unquoted keys, single-quoted strings, and more.
import config from "./config.json5";
console.log(config);
// via import attribute:
import data from "./data.txt" with { type: "json5" };
During bundling, the parsed JSON5 is inlined into the bundle as a JavaScript object.
var config = {
name: "my-app",
version: "1.0.0",
// ...other fields
};
If a .json5 file is passed as an entrypoint, it will be converted to a .js module that export defaults the parsed object.
InputOutput{
// Configuration
name: "John Doe",
age: 35,
email: "johndoe@example.com",
}
text
Text loader. Default for .txt.
The contents of the text file are read and inlined into the bundle as a string.
Text files can be directly imported. The file is read and returned as a string.
import contents from "./file.txt";
console.log(contents); // => "Hello, world!"
// To import an html file as text
// The "type' attribute can be used to override the default loader.
import html from "./index.html" with { type: "text" };
When referenced during a build, the contents are inlined into the bundle as a string.
var contents = `Hello, world!`; console.log(contents);If a .txt file is passed as an entrypoint, it will be converted to a .js module that export defaults the file contents. InputOutput
Hello, world!napi Native addon loader. Default for .node. In the runtime, native addons can be directly imported.
import addon from "./addon.node"; console.log(addon);In the bundler, .node files are handled using the file loader. sqlite SQLite loader. with { "type": "sqlite" } import attribute In the runtime and bundler, SQLite databases can be directly imported. This will load the database using bun:sqlite.
import db from "./my.db" with { type: "sqlite" };
This is only supported when the target is bun.
By default, the database is external to the bundle (so that you can potentially use a database loaded elsewhere), so the database file on-disk won’t be bundled into the final output.
You can change this behavior with the "embed" attribute:
// embed the database into the bundle
import db from "./my.db" with { type: "sqlite", embed: "true" };
When using a standalone executable, the database is embedded into the single-file executable.
Otherwise, the database to embed is copied into the outdir with a hashed filename.
html
The html loader processes HTML files and bundles any referenced assets. It will:
Bundle and hash referenced JavaScript files ( File Types - Bun,AI智能索引,全网链接索引,智能导航,网页索引
- File types and loaders supported by Bun