`codebase-memory-mcp dev` (built from source via NixOS flake, `github:DeusData/codebase-memory-mcp`)

[kortschak]

Version

e599df1

Platform

Linux (x64)

Install channel

Built from source

Binary variant

standard

What happened, and what did you expect?

After codebase-memory-mcp install on NixOS, every Claude Code session start showed:

SessionStart:resume [~/.claude/hooks/cbm-session-reminder] failed with non-blocking
status code 127: /bin/sh: line 1: /home/<user>/.claude/hooks/cbm-session-reminder: cannot
execute: required file not found

The hooks installed by codebase-memory-mcp install have #!/bin/bash shebangs. On NixOS, /bin/bash does not exist — only /bin/sh (which is bash, but only via a NixOS-managed symlink). When Claude Code executes the hook, /usr/bin/env searches a stripped PATH that does not include the directory containing bash, so env bash also fails. The fix is to use the absolute path to bash: #!/run/current-system/sw/bin/bash.

Expected: the hooks install with a portable shebang (e.g. #!/usr/bin/env bash) and Claude Code runs hooks with a PATH that includes standard binary locations, or the install script detects the system bash path and uses it directly.

Reproduction

1. Install NixOS (any recent release). /bin/bash does not exist; bash lives at /run/current-system/sw/bin/bash.
2. Install codebase-memory-mcp from the flake (see details) and run codebase-memory-mcp install targeting Claude Code.
3. Start a new Claude Code session.
4. Observe the status code 127 error for cbm-session-reminder and cbm-code-discovery-gate.

Workaround applied: replace #!/bin/bash with #!/run/current-system/sw/bin/bash in both hook files.

A more portable fix would be for the install script to detect the system bash path (e.g. $(command -v bash)) and write that into the shebang, or to ensure Claude Code's hook runner provides a PATH that includes standard binary directories.

Details

flake.lock

{
  "nodes": {
    "codebase-memory-mcp": {
       "inputs": {
         "nixpkgs": [
           "nixpkgs"
         ]
       },
       "locked": {
         "lastModified": 1781281003,
         "narHash": "sha256-jFIZ3+EgNUK3z/6dg0U4idxmp0UHa8Zk79Z36dhE3hg=",
         "owner": "DeusData",
         "repo": "codebase-memory-mcp",
         "rev": "e599df1d563c1e9b0b2fc8c6b12ee85934ade1c5",
         "type": "github"
       },
       "original": {
         "owner": "DeusData",
         "repo": "codebase-memory-mcp",
         "type": "github"
       }
     },
     <more>

flake.nix

   <more>
   codebase-memory-mcp = {
     url = "github:DeusData/codebase-memory-mcp";
     inputs.nixpkgs.follows = "nixpkgs";
   };
   <more>

Logs

/bin/sh: line 1: /home/<user>/.claude/hooks/cbm-session-reminder: cannot execute: required file not found

strace output showing env searching a PATH without any directory containing bash:

execve("/nix/store/.../zplug-2.4.2/share/zplug/bin/bash", ...) = -1 ENOENT
execve("/home/<user>/bin/bash", ...) = -1 ENOENT
execve("/home/<user>/.local/bin/bash", ...) = -1 ENOENT
execve("/run/wrappers/bin/bash", ...) = -1 ENOENT
execve("/home/<user>/.nix-profile/bin/bash", ...) = -1 ENOENT

Project scale (if relevant)

53 nodes / 52 edges (small NixOS config repo)

Confirmations

• I searched existing issues and this is not a duplicate.
• My reproduction uses shareable code (a dummy snippet or a public OSS repository), not proprietary code.

[DeusData]

Hey, thx for sharing. Will dig into this once I find the time