![Graphic for bun fmt and bun lint --staged. Format and lint only what you're committing. One line in a git hook, nothing to install. Step 1, create this file: .git/hooks/pre-commit, a plain text file made executable with chmod +x, containing "#!/bin/sh" and "bun fmt --staged && bun lint --staged". Step 2, commit: a terminal runs git commit -m "add cart". bun fmt prints "src/cart.ts" and "Formatted 1 file, 0 unchanged [8.10ms]", with a sticker reading "re-staged". bun lint then prints a code frame pointing at a debugger statement in src/cart.ts line 2, "error: Unexpected 'debugger' statement. no-debugger", "1 problem (1 error, 0 warnings)" and "Linted 1 file [7.94ms]". A stamp reads "commit blocked".](/pic/orig/media%2FHUrPzjragAAAruk.jpg)
In the next version of Bun
bun lint is a 26x faster ESLint-compatible linter with over 1,000 builtin rules - reads eslint & oxlint configs.
bun lint is a 26x faster ESLint-compatible linter with over 1,000 builtin rules - reads eslint & oxlint configs.
55
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1,151
In the next version of Bun
`bun fmt` is a 320x faster Prettier alternative
Passes 99% of Prettier's test suite & supports 20 languages
`bun fmt` is a 320x faster Prettier alternative
Passes 99% of Prettier's test suite & supports 20 languages
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Some of the language changes when TypeScript types become real (with ahead-of-time compilation)
74
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Claude automatically gets XML formatted type errors which sometimes reduces the number of tool calls needed to fix the error (due to the source preview), reducing token usage
1
0
17
In the next version of Bun
`bun --check <file.ts>` runs Bun’s typescript type checker before running the file
`bun --check <file.ts>` runs Bun’s typescript type checker before running the file
14
4
340
In the next version of Bun
`bun check` is a TypeScript type checker builtin to Bun (written in Rust)
`bun check` is a TypeScript type checker builtin to Bun (written in Rust)
69
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Today, Bun is a JavaScript runtime, bundler, test runner, and a package manager.
Soon, Bun will also be a
Soon, Bun will also be a
202
29
968
In the next version of Bun
Enabling profile-guided optimization for bytecode improves startup time by up to 2x
`bun build --compile --bytecode --bytecode-order=./file`
Enabling profile-guided optimization for bytecode improves startup time by up to 2x
`bun build --compile --bytecode --bytecode-order=./file`
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VIA QUOTE POST
PRIVILEGED & CONFIDENTIAL
FOR SETTLEMENT PURPOSES ONLY (FED. R. EVID. 408)
September 22, 2026
Mr. Alexandr Wang
@alexandr_wang
Re: Unauthorized Use of the BUN® Design Mark, U.S. Reg. No. 7,585,721; Proposed “Muse Merch Store”; Demand to Cease and Desist; Notice of Lg:
Bun (“Bun,” “Registrant,” or “the Bun”) is the owner of all right, title, and interest in and to U.S. Registration No. 7,585,721, issued December 3, 2024 on the Principal Register, for a mark consisting of “a bread bun with a smiling face,” wherein “the bun has black and white eyes,” “pink cheeks and a pink and dark pink mouth outlined in black,” the colors tan, dark tan, pink, dark pink, black and white being claimed as a feature of the mark (the “BUN® Mark”), which registration constitutes prima facie evidence of the validity of the BUN® Mark and of Bun’s exclusive right to use the same pursuant to 15 U.S.C. § 1057(b), and constructive notice of Bun’s claim of ownership thereof pursuant to 15 U.S.C. § 1072, such that ignorance of the Bun shall be no defense. The United States Patent and Trademark Office has further classified the BUN® Mark under Design Search Code 02.01.34 (“Monsters (not robots)”), a classification Bun has at all times accepted without objection.
It has come to Bun’s attention that you, together with your affiliates, agents, successors, assigns, and any superintelligences acting in concert therewith (collectively, “You”), have announced an intent to open a “muse merch store” and have commenced “market research” in connection therewith, publicly displaying goods including without limitation one (1) t-shirt, one (1) bucket hat, one (1) beanie, one (1) sock (singular), one (1) pin set (3-pack), and assorted keychains, patches, plush and tote bags (collectively, the “Infringing Goods”), each bearing a tan, round figure having black eyes, pink cheeks and a smiling face (the “Musey”), which is, upon information and belief, also a monster, and not a robot.
Under the factors set forth in AMF Inc. v. Sleekcraft Boats, 599 F.2d 341 (9th Cir. 1979), the likelihood of confusion is overwhelming: the marks are similar in sight, sound (none), and meaning (bun); the goods are proximate; Bun has long contemplated expansion into bucket hats; and consumers who have expressed a willingness to exchange a right kidney for the Infringing Goods cannot be said to be exercising the degree of care ordinarily expected of a reasonably prudent purchaser.
Accordingly, Bun hereby demands that You immediately (i) cease and desist from any and all manufacture, sale, offering for sale, patting, and market research of or relating to the Infringing Goods; (ii) deliver up all Infringing Goods for destruction pursuant to 15 U.S.C. § 1118, or for cuddling, at Bun’s sole discretion; (iii) provide a full accounting of all profits, market capitalization, and kidneys received; and (iv) preserve all documents, electronically stored information, and plush, whether stuffed or unstuffed, pending final resolution of this matter.
Nothing herein constitutes a complete statement of the relevant facts or a waiver of any rights, remedies, or crumbs, including without limitation those arising under 15 U.S.C. §§ 1114, 1116, 1117, and 1125(a) and (c) (Bun being, upon information and belief, famous), all of which are expressly reserved. Time is of the essence.
Govern yourself accordingly.
Very truly yours,
Bun
Enclosures: Exhibits A–B
cc: The Musey (via pat)
Exhibits
PRIVILEGED & CONFIDENTIAL
FOR SETTLEMENT PURPOSES ONLY (FED. R. EVID. 408)
September 22, 2026
Mr. Alexandr Wang
@alexandr_wang
Re: Unauthorized Use of the BUN® Design Mark, U.S. Reg. No. 7,585,721; Proposed “Muse Merch Store”; Demand to Cease and Desist; Notice of Lg:
Bun (“Bun,” “Registrant,” or “the Bun”) is the owner of all right, title, and interest in and to U.S. Registration No. 7,585,721, issued December 3, 2024 on the Principal Register, for a mark consisting of “a bread bun with a smiling face,” wherein “the bun has black and white eyes,” “pink cheeks and a pink and dark pink mouth outlined in black,” the colors tan, dark tan, pink, dark pink, black and white being claimed as a feature of the mark (the “BUN® Mark”), which registration constitutes prima facie evidence of the validity of the BUN® Mark and of Bun’s exclusive right to use the same pursuant to 15 U.S.C. § 1057(b), and constructive notice of Bun’s claim of ownership thereof pursuant to 15 U.S.C. § 1072, such that ignorance of the Bun shall be no defense. The United States Patent and Trademark Office has further classified the BUN® Mark under Design Search Code 02.01.34 (“Monsters (not robots)”), a classification Bun has at all times accepted without objection.
It has come to Bun’s attention that you, together with your affiliates, agents, successors, assigns, and any superintelligences acting in concert therewith (collectively, “You”), have announced an intent to open a “muse merch store” and have commenced “market research” in connection therewith, publicly displaying goods including without limitation one (1) t-shirt, one (1) bucket hat, one (1) beanie, one (1) sock (singular), one (1) pin set (3-pack), and assorted keychains, patches, plush and tote bags (collectively, the “Infringing Goods”), each bearing a tan, round figure having black eyes, pink cheeks and a smiling face (the “Musey”), which is, upon information and belief, also a monster, and not a robot.
Under the factors set forth in AMF Inc. v. Sleekcraft Boats, 599 F.2d 341 (9th Cir. 1979), the likelihood of confusion is overwhelming: the marks are similar in sight, sound (none), and meaning (bun); the goods are proximate; Bun has long contemplated expansion into bucket hats; and consumers who have expressed a willingness to exchange a right kidney for the Infringing Goods cannot be said to be exercising the degree of care ordinarily expected of a reasonably prudent purchaser.
Accordingly, Bun hereby demands that You immediately (i) cease and desist from any and all manufacture, sale, offering for sale, patting, and market research of or relating to the Infringing Goods; (ii) deliver up all Infringing Goods for destruction pursuant to 15 U.S.C. § 1118, or for cuddling, at Bun’s sole discretion; (iii) provide a full accounting of all profits, market capitalization, and kidneys received; and (iv) preserve all documents, electronically stored information, and plush, whether stuffed or unstuffed, pending final resolution of this matter.
Nothing herein constitutes a complete statement of the relevant facts or a waiver of any rights, remedies, or crumbs, including without limitation those arising under 15 U.S.C. §§ 1114, 1116, 1117, and 1125(a) and (c) (Bun being, upon information and belief, famous), all of which are expressly reserved. Time is of the essence.
Govern yourself accordingly.
Very truly yours,
Bun
Enclosures: Exhibits A–B
cc: The Musey (via pat)
Exhibits
we are considering opening a muse merch store
i am doing market research
how excited you would be by muse merch, from a scale of "meh" to "you can have my right kidney"?
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@barsisyphus @github @turbopuffer @posthog @exedev @AntithesisHQ @TigerBeetleDB @digitalocean @ClaudeDevs 9? should be at least 2
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![Benchmark 1: bun --print 1234
Time (mean ± σ): 3.8 ms ± 0.2 ms [User: 2.8 ms, System: 1.0 ms]
Range (min … max): 3.4 ms … 4.5 ms 795 runs
Benchmark 2: bun-1.4.0 --print 1234
Time (mean ± σ): 4.9 ms ± 0.3 ms [User: 3.2 ms, System: 1.7 ms]
Range (min … max): 4.1 ms … 5.6 ms 544 runs
Benchmark 3: node --print 1234
Time (mean ± σ): 26.9 ms ± 1.8 ms [User: 14.6 ms, System: 11.9 ms]
Range (min … max): 23.7 ms … 30.7 ms 113 runs
Summary
bun --print 1234 ran
1.27 ± 0.11 times faster than bun-1.4.0 --print 1234
7.01 ± 0.58 times faster than node --print 1234](/pic/orig/media%2FHRV2Zjva0AA0taP.jpg)
Bun v1.4.1 is a big upgrade to Bun’s bundler.
On a 200-route React app over simulated 4G, navigating between routes is 38% faster than Bun v1.4.0, and 10% faster than Vite v8.2.2.
On a 200-route React app over simulated 4G, navigating between routes is 38% faster than Bun v1.4.0, and 10% faster than Vite v8.2.2.
18
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687
In the next version of Bun
Bun's bundler gets smarter about tree-shaking ESM that uses `export * as ns` syntax
Bun's bundler gets smarter about tree-shaking ESM that uses `export * as ns` syntax
9
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416
In the next version of Bun
`bun build --splitting` injects `<link rel="modulepreload">`, helping webpages load faster by reducing network waterfalls
`bun build --splitting` injects `<link rel="modulepreload">`, helping webpages load faster by reducing network waterfalls
8
25
848
In the next version of Bun
`Bun.serve({ http2: true })` enables HTTP/2 support. The same API just works for HTTP/1.1, HTTP/2, and HTTP/3.
`Bun.serve({ http2: true })` enables HTTP/2 support. The same API just works for HTTP/1.1, HTTP/2, and HTTP/3.
5
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`--bytecode` used to cost ~7x your source size on disk and ~4x in memory, in exchange for faster startup.
Now its ~3x on disk, almost free in memory, and starts faster than before.
This is a large test app, so the absolute numbers are higher than what most would see.
Now its ~3x on disk, almost free in memory, and starts faster than before.
This is a large test app, so the absolute numbers are higher than what most would see.
2
1
70
In the next version of Bun
Compiled executables with bytecode start 17% faster, get 30% smaller, and use 30% less memory on start
Compiled executables with bytecode start 17% faster, get 30% smaller, and use 30% less memory on start
12
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860
JavaScript files use Bun's JS parser to AST diff and reformat it. This makes diffs of minified source code readable, which makes it a little harder for supply chain attacks to hide.
2
1
64
In the next version of Bun
`bun pm diff <package@version> <package@version2>` shows code changes between versions (un-minified)
`bun pm diff <package@version> <package@version2>` shows code changes between versions (un-minified)
21
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407
In the next version of Bun
Web APIs like `URL`, `Headers`, and `URLSearchParams` get up to 4x faster
Web APIs like `URL`, `Headers`, and `URLSearchParams` get up to 4x faster
22
17
675
In the next version of Bun
The `cgroup` option in `Bun.spawn` lets you limit cpu & memory usage of spawned processes on Linux
The `cgroup` option in `Bun.spawn` lets you limit cpu & memory usage of spawned processes on Linux
27
22
745
In the next version of Bun
`bun dedupe` deduplicates semver-compatible resolved package versions
`bun dedupe` deduplicates semver-compatible resolved package versions
8
14
573
In the next version of Bun
We fixed a GC retention cycle that made Next.js App Router SSR leak memory when a page called fetch()
We fixed a GC retention cycle that made Next.js App Router SSR leak memory when a page called fetch()
23
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683
In the next version of Bun
Saving streaming file uploads to disk via Bun.write uses 35x less memory compared to Bun v1.3.14
Saving streaming file uploads to disk via Bun.write uses 35x less memory compared to Bun v1.3.14
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537
Closed 911 issues as completed in the last 24 hrs.
Many fixed in recent PRs. Some fixed long ago.
Many fixed in recent PRs. Some fixed long ago.
21
8
620
In the next version of Bun
node:sqlite is fully implemented and passes 100% of Node.js’ test suite
node:sqlite is fully implemented and passes 100% of Node.js’ test suite
21
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988
the next version of Bun
93% of node:http2 tests from the Node.js v26 test suite pass, thanks to @cirospaciari
93% of node:http2 tests from the Node.js v26 test suite pass, thanks to @cirospaciari
4
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324
In the next version of Bun
94% of node:http tests from the Node.js v26 test suite pass, thanks to @cirospaciari
94% of node:http tests from the Node.js v26 test suite pass, thanks to @cirospaciari
7
9
655
In the next version of Bun
The `"compress"` option in `fetch` compresses the request body for you
The `"compress"` option in `fetch` compresses the request body for you
12
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736
In the next version of Bun
`process` emits a "memoryPressure" event when the system runs low on memory (thanks @codebytere!)
`process` emits a "memoryPressure" event when the system runs low on memory (thanks @codebytere!)
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