Segfault on Windows 11 Enterprise with Citrix — ctiuser.dll in crash stack

Bug report

Environment:

• Claude Code v2.1.42
• Bun Canary v1.3.9-canary.62 (6d2fefba) Windows x64 (baseline)
• Windows 11 Enterprise 10.0.26200
• CPU: sse42 avx avx2
• Citrix installed (enterprise environment)

Description

Claude Code crashes with a segmentation fault on Windows 11 Enterprise machines with Citrix installed. The Bun runtime panics with a segfault at address 0x113, and the crash stack includes ctiuser.dll (a Citrix DLL that is injected into processes).

• Works: Launching claude from C:\Users\<user> (home directory)
• Crashes: Launching claude from any subdirectory (e.g., C:\Users\<user>\Documents, C:\Users\<user>\Projects)

The crash is reproducible and consistent across different subdirectories, including freshly-created empty folders.

Crash output

panic(main thread): Segmentation fault at address 0x113
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

Bun crash report link: https://bun.report/1.3.9/e_26d2fefbGugogCCWctiuser.dllgmvdCWctiuser.dllohkdCYKERNEL32.DLLsu+JCcKERNELBASE.dlloi7sBCcKERNELBASE.dllsh9rBCYKERNEL32.DLLotjPCWctiuser.dlluz1by8hmqCi144RglgkvB0to7uB__qt24tCA2AmR

Stack trace DLLs

• ctiuser.dll (Citrix — appears multiple times)
• KERNEL32.DLL
• KERNELBASE.dll

Steps to reproduce

1. Have Citrix Workspace installed (Windows 11 Enterprise)
2. Install Claude Code via WinGet
3. Open a terminal and cd into any subdirectory under the user home folder
4. Run claude
5. The welcome screen renders, then Bun crashes with a segfault

Expected behavior

Claude Code should start normally without crashing.

Additional context

The crash appears to be caused by Citrix's ctiuser.dll DLL injection conflicting with Bun's runtime. This likely affects any Windows Enterprise environment with Citrix installed. The fact that it works from the home directory but not subdirectories suggests a timing or initialization-order issue in how the injected DLL interacts with Bun's memory management.