[BUG] Bun crashes leads to Claude Code crashing

I have the same problem. It looks like it’s a Bun bug. The log output essentially confirms this.

PS C:\Users\[MASKED_CURRENT_DIRECTORY]> claude
============================================================
Bun v1.2.23 (cf136713) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2 avx512
Args: "C:\Users\[MASKED_USER_NAME]\.local\bin\claude.exe"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) dotenv(2) jsc spawn standalone_executable
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:domain" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:string_decoder" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node-fetch" "node:inspector" "node:http2"
Elapsed: 657ms | User: 609ms | Sys: 156ms
RSS: 0.31GB | Peak: 0.31GB | Commit: 0.40GB | Faults: 77281 | Machine: 16.83GB

panic(main thread): Unexpected error
ENOTCONN: Transport endpoint is not connected (open())
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

three more times today and below is from the last one

<img width="1917" height="725" alt="Image" src="https://github.com/user-attachments/assets/6a04fe02-d955-4aeb-a7f6-82dcb17717a2" />

And again!!

<sarcasm>Is this just a way for me to burn more tokens as I have to do the task again!! </sarcasm>

● Read(D:\Development\IndyDevDan\TAC\tac-8\tac8_app3__out_loop_multi_agent_task_board\.claude\commands\plan.md)
⎿  Read 112 lines
⎿  Running PostToolUse hook…

∴ Thought for 1s (ctrl+o to show thinking)

· Symbioting… (esc to interrupt)

────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
git:feature/SP-284-Vii | D:\Development\starrpos | ctx:run /context Thinking on (tab to toggle)
============================================================
Bun v1.3.0 (b0a6feca) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2
Args: "C:\Users\RichardMoore\.local\bin\claude.exe"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) fetch(146) jsc spawn(209) standalone_executable
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:domain" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:string_decoder" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node-fetch" "node:inspector" "node:http2" "node:diagnostics_channel"
Elapsed: 53937ms | User: 11890ms | Sys: 4703ms
RSS: 0.47GB | Peak: 0.62GB | Commit: 0.58GB | Faults: 580295 | Machine: 34.19GB

panic(main thread): Segmentation fault at address 0xFFFFFFFFFFFFFFFF
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

To send a redacted crash report to Bun's team,
please file a GitHub issue using the link below:

https://bun.report/1.3.0/e_1b0a6fecAz/7v//Bg6y+zB6jx+zByo95IwjlnG2pwisByuxvFmwZqhJoq1p3DCYKERNEL32.DLLut0LCSntdll.dll4t0EA2DD

FYI, Rather then use Warp as my terminal I've been trying the Windows native one for a few hours and so far no errors

:)

<img width="1333" height="326" alt="Image" src="https://github.com/user-attachments/assets/a7eee3e5-0c2f-42bb-9ed4-f7ffc6533e4b" />

Bun v1.3.2 (b131639c) Linux x64 (baseline)
Linux Kernel v6.17.0 | glibc v2.42
CPU: sse42 popcnt avx avx2
Args: "claude"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) fetch(78) jsc spawn(20) standalone_executable workers_spawned(9) workers_terminated(9)
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:domain" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node-fetch" "node:inspector" "node:http2" "node:diagnostics_channel"
Elapsed: 7415ms | User: 6562ms | Sys: 2171ms
RSS: 0.84GB | Peak: 1.25GB | Commit: 0.84GB | Faults: 0 | Machine: 0.18TB

panic(main thread): Segmentation fault at address 0xE8
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

i seem to be experiencing a similar issue, but running in a container on Linux, Claude Code v2.0.65, with Haiku 4.5.

<img width="1295" height="633" alt="Image" src="https://github.com/user-attachments/assets/c692b9f8-7810-40da-910b-6256a6920bc0" />

at any rate, it's a Bun segfault, quite some time (and tokens!) into the session. bummer.

============================================================
Bun v1.3.4 (5eb2145b) Linux x64 (baseline)
Linux Kernel v4.15.0 | glibc v2.39
CPU: sse42 popcnt avx avx2
Args: "claude"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) fetch(16) jsc spawn(52) standalone_executable process_dlopen 
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:domain" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node-fetch" "node:inspector" "node:http2" 
Elapsed: 1322896ms | User: 157016ms | Sys: 56321ms
RSS: 34.20MB | Peak: 0.47GB | Commit: 34.20MB | Faults: 2 | Machine: 16.67GB

panic: Segmentation fault at address 0x0
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

should i open a separate ticket for a Bun segfault on Linux as this one says platform:windows?

P.S. hopefully we can expect a blazing fast resolution, now that Bun folks have joined Anthropic, and all? 😉

This issue has been inactive for 30 days. If the issue is still occurring, please comment to let us know. Otherwise, this issue will be automatically closed in 30 days for housekeeping purposes.

I am still facing this issue.

Bun v1.3.5 (1e86cebd) macOS Silicon
macOS v15.7
CPU: fp aes crc32 atomics
Args: "claude" "--continue"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) abort_signal(4) fetch(10) jsc spawn(21) standalone_executable process_dlopen
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/posix" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node-fetch" "node:http2"
Elapsed: 94060ms | User: 19085ms | Sys: 1753ms
RSS: 0.38GB | Peak: 0.51GB | Commit: 1.00GB | Faults: 72 | Machine: 17.18GB

panic(main thread): Bus error at address 0x20202020200ABABB
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

To send a redacted crash report to Bun's team,
please file a GitHub issue using the link below:

 https://bun.report/1.3.5/M_11e86cebmgEuhogC__A4giwgkgB2r9qhgB

Bun v1.3.10 (1423d3c8) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2
Args: "C:\Users\cso-c\.local\bin\claude.exe"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) abort_signal(27) fetch(86) jsc spawn(100) standalone_executable process_dlopen(3) yaml_parse(232)
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/posix" "node:path/win32" "node:perf_hooks" "node:process" "node:stream" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "node:worker_threads" "undici" "ws" "node:http2"
Elapsed: 996262ms | User: 35562ms | Sys: 15375ms
RSS: 1.31GB | Peak: 1.49GB | Commit: 1.88GB | Faults: 1963656 | Machine: 68.39GB

panic(main thread): Segmentation fault at address 0xFFFFFFFFFFFFFFFF
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

how to fix it ? looks that I have this issue since I switched to subscription mode

it's annoying , FIX it

Still Unresolved — This Was One of the First Reports

This issue was filed months ago. The Bun crash problem on Windows has only expanded since — now 20+ separate issues, 90+ unique affected users.

v2.1.53 shipped 4 targeted crash fixes (WASM, ARM64, spawn panic, corrupted value). They helped with specific crash modes but the core N-API race condition in Bun v1.3.10 is untouched. Crashes continue on v2.1.55.

Root cause analysis with 27 memory dumps: #21875. Full timeline (26+ repros, 4 computer lockups): #21576.

Closing for now — inactive for too long. Please open a new issue if this is still relevant.

This issue has been automatically locked since it was closed and has not had any activity for 7 days. If you're experiencing a similar issue, please file a new issue and reference this one if it's relevant.