vmux/.planning/phases/01-session-discovery/01-01-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
01-session-discovery	01	process-detection	go proc linux cli		Go module scaffold (shell.nix, go.mod) Shared types: Process, Session, SessionState FindClaudeProcesses() scanning /proc for Claude PIDs EncodePath() converting absolute paths to ~/.claude/projects/ folder names	01-02 02-session-state	added patterns go-1.25 go-stdlib-os injectable-procdir-for-testing fake-proc-fixtures	created modified shell.nix go.mod types.go proc.go proc_test.go	filepath.Base matching for Claude binary detection (handles full paths) procDir parameter injection for testability (no hardcoded /proc)	Fake /proc fixtures: createFakeProc() builds temp dirs with cmdline files and cwd symlinks Silent error skipping: permission denied and vanished processes are skipped, not fatal	DISC-01 DISC-02	2min	2026-03-23

Phase 01 Plan 01: Scaffolding + Process Detection Summary

Go module with FindClaudeProcesses() scanning /proc for active Claude Code PIDs and EncodePath() for session folder mapping

Performance

• Duration: 2 min
• Started: 2026-03-23T12:23:44Z
• Completed: 2026-03-23T12:25:44Z
• Tasks: 2
• Files created: 5

Accomplishments

• Go project scaffolded with NixOS shell.nix, go.mod, and shared types (Process, Session, SessionState)
• FindClaudeProcesses() scans configurable /proc directory, filters by "claude" binary name, reads cwd via Readlink
• EncodePath() converts paths to ~/.claude/projects/ folder format (replace / and . with -)
• 5 tests covering normal detection, permission denied, empty proc, and path encoding edge cases

Task Commits

Each task was committed atomically:

1. Task 1: Scaffolding projet + types partages - 12e1ba7 (feat)
2. Task 2 RED: Failing tests for proc scanning - 81ee7dc (test)
3. Task 2 GREEN: Implement FindClaudeProcesses and EncodePath - 166e441 (feat)

Files Created/Modified

• shell.nix - NixOS dev environment with go and gopls
• go.mod - Go module github.com/pieMusic/vmux
• types.go - Shared types: Process, Session, SessionState (Working/NeedsInput/Idle/Unknown)
• proc.go - FindClaudeProcesses() and EncodePath()
• proc_test.go - 5 unit tests with fake /proc fixtures

Decisions Made

• Used filepath.Base(parts[0]) for binary detection to handle full paths like /nix/store/.../claude
• Injected procDir as parameter for full testability without mocking os functions

Deviations from Plan

None - plan executed exactly as written.

Issues Encountered

• shell.nix was in Pierre's global gitignore; force-added with git add -f since it is project-specific

User Setup Required

None - no external service configuration required.

Next Phase Readiness

• Types and process detection ready for plan 01-02 (JSONL session matching, state heuristics, display)
• EncodePath enables PID-to-session folder mapping

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Phase: 01-session-discovery Completed: 2026-03-23