--- title: Bun v1.3.3 description: "Fixes 95 issues (addressing 348 👍). CompressionStream and DecompressionStream, Control .env and bunfig.toml loading in standalone executables, `retry` and `repeats` in `bun:test`, --no-env-file, SQLite 3.51.0, Upgraded to Zig 0.15.2, Bugfixes for bundler, bun install, Windows, Node.js compatibility, Web APIs, Bun.serve, networking, Bun.YAML, Bun.Transpiler, Bun.spawn & TypeScript definitions" date: "2025-11-21T10:11:00.000Z" author: jarred --- This release fixes 95 issues (addressing 348 👍 reactions)! #### To install Bun {% codetabs %} ```sh#curl $ curl -fsSL https://bun.sh/install | bash ``` ```sh#npm $ npm install -g bun ``` ```sh#powershell $ powershell -c "irm bun.sh/install.ps1|iex" ``` ```sh#scoop $ scoop install bun ``` ```sh#brew $ brew tap oven-sh/bun $ brew install bun ``` ```sh#docker $ docker pull oven/bun $ docker run --rm --init --ulimit memlock=-1:-1 oven/bun ``` {% /codetabs %} #### To upgrade Bun ```sh $ bun upgrade ``` ## CompressionStream and DecompressionStream Bun now implements [`CompressionStream`](https://developer.mozilla.org/en-US/docs/Web/API/CompressionStream) and [`DecompressionStream`](https://developer.mozilla.org/en-US/docs/Web/API/DecompressionStream). These standard Web APIs allow for streaming compression and decompression of data without buffering the entire payload in memory. In addition to the standard `"gzip"`, `"deflate"`, and `"deflate-raw"` formats, Bun also supports `"brotli"` and `"zstd"`. ```js const response = await fetch("https://example.com"); // Compress the response body using gzip const compressed = response.body.pipeThrough(new CompressionStream("gzip")); // Or use zstd for faster compression const zstd = response.body.pipeThrough(new CompressionStream("zstd")); ``` Thanks to @nektro for the contribution! ## Control .env and bunfig.toml loading in standalone executables Standalone executables created with `bun build --compile` normally look for `.env` and `bunfig.toml` files in the directory where the executable is run. You can now disable this behavior at build time using the `--no-compile-autoload-dotenv` and `--no-compile-autoload-bunfig` flags. This is useful when you want to ensure the executable behaves deterministically, regardless of the configuration files present in the user's working directory. ```bash # Disable .env and bunfig.toml loading bun build --compile --no-compile-autoload-dotenv --no-compile-autoload-bunfig app.ts ``` You can also configure this via the JavaScript API: ```js await Bun.build({ entrypoints: ["./app.ts"], compile: { // Disable .env loading autoloadDotenv: false, // Disable bunfig.toml loading autoloadBunfig: false, }, }); ``` ## `retry` and `repeats` in `bun:test` You can now use the `retry` and `repeats` options in `bun:test`. `retry` runs the callback function up to the specified number of times and if the test passes once then the test passes, while `repeats` runs the callback function up to the specified number of times and if the test fails once then the test fails. This is useful for handling flaky tests. ```ts import { test } from "bun:test"; test( "flaky test", () => { if (Math.random() > 0.1) throw new Error("fail"); }, { retry: 3 }, ); test( "check for flakiness", () => { // run this 20 times to ensure it's stable }, { repeats: 20 }, ); ``` Thanks to @pfgithub for the contribution! ## --no-env-file You can now disable Bun's automatic `.env` file loading using the `--no-env-file` flag. This is useful in production environments or CI/CD pipelines where you want to rely solely on system environment variables. ```bash bun run --no-env-file index.ts ``` This can also be configured in `bunfig.toml`: ```toml # Disable loading .env files env = false ``` Explicitly provided environment files via `--env-file` will still be loaded even when default loading is disabled. ## SQLite 3.51.0 `bun:sqlite` has been updated to SQLite v3.51.0. ```js import { Database } from "bun:sqlite"; const db = new Database(); console.log(db.prepare("SELECT sqlite_version()").get()); // { "sqlite_version()": "3.51.0" } ``` ## Internal: Upgraded to Zig 0.15.2 Bun is now built with Zig 0.15.2. This reduces the binary size by 0.8MB and improves build times for contributors. ### Bundler fixes - Fixed: A rare panic in the dev server when processing CSS assets in the incremental graph - Fixed: A rare panic in the dev server that could occur when a file referenced by a dynamic import is deleted during a reload ### bun install fixes - Fixed: A rare crash during `bun install` involving optional peer dependencies - Fixed: A regression in `bun install` when parsing git dependency URLs with a leading hash - Fixed: A regression from Bun v1.3.2 that could cause `bun ls --all` with unresolved optional peer dependencies to crash - Fixed: A regression from Bun v1.3.2 where `sharp` versions older than v0.33.0 failed to install correctly ### Windows fixes - Fixed: `process.stdout` now emits `'resize'` events and `SIGWINCH` signals on Windows, which fixes terminal resizing issues in Claude Code & OpenCode on Windows - Improved: `bun getcompletes` works on Windows - Fixed: a crash on Windows when laptop hibernates and then wakes up and resumes execution after a Worker thread had been terminated ### Node.js compatibility improvements - Implemented: `_handle.fd` in `node:net` and `node:tls` for better compatibility with libraries that rely on the socket file descriptor - Fixed: N-API bug preventing `rspack` or `rsbuild` from working ### Web APIs fixes - Fixed: fuzzer-discovered crash when using JSON.stringify on a FormData object in rare cases - Fixed: fuzzer-discovered crash when calling `stream` on a Blob in certain edge cases - Fixed: sanitizer-discovered memory leak in `Blob` ### Bun.serve - Fixed: An issue where Unicode characters in `Bun.serve` static `Response` objects given a string as input were missing the `Content-Type` header ### Networking - Fixed: sanitizer-discovered memory leak in `node:net.SocketAddress` when passing an invalid port - Fixed: sanitizer-discovered memory leak in `Bun.listen` when errors are thrown during socket creation ### YAML - Fixed: `Bun.YAML.stringify` would incorrectly serialize strings with leading zeros as numbers - Fixed: A performance issue where YAML merge keys could cause parsing to hang due to exponential complexity ### Transpiler - Fixed: fuzzer-discovered crash in `new Bun.Transpiler()` with invalid configuration ### Bun.spawn - Fixed: A small memory leak in `Bun.spawn` when passing extra non-IPC, non-stdout, non-stderr, and non-stdin file descriptors ### TypeScript definitions - Fixed: Added JSDoc documentation for `configVersion` in `BunLockFile` type definition - Fixed: Added missing `"css"`, `"jsonc"`, `"yaml"`, and `"html"` to the `Loader` type definition - Fixed: Removed unnecessary dependency on `@types/react` in `@types/bun` ### Security - Fixed: Updated root certificates to Mozilla NSS 3.117 ### bun upgrade fixes - Improved: `bun upgrade` now displays download sizes in human-readable units (e.g. `23.2MiB`) instead of raw bytes ### Thanks to 19 contributors! - [@alii](https://github.com/alii) - [@braden-w](https://github.com/braden-w) - [@cirospaciari](https://github.com/cirospaciari) - [@connerlphillippi](https://github.com/connerlphillippi) - [@dioro](https://github.com/dioro) - [@dylan-conway](https://github.com/dylan-conway) - [@halil-pan](https://github.com/halil-pan) - [@hona](https://github.com/hona) - [@lydiahallie](https://github.com/lydiahallie) - [@markovejnovic](https://github.com/markovejnovic) - [@minigod](https://github.com/minigod) - [@nathanosoares](https://github.com/nathanosoares) - [@nektro](https://github.com/nektro) - [@ocodista](https://github.com/ocodista) - [@pfgithub](https://github.com/pfgithub) - [@riskymh](https://github.com/riskymh) - [@robobun](https://github.com/robobun) - [@yinheli](https://github.com/yinheli)