Git worktrees solved our parallel-agent file conflicts. The test environment was harder.

Git worktrees effectively resolved file conflicts when developers worked on multiple tasks in parallel, each in its own branch and worktree. However, ensuring browser and end-to-end tests exercised the correct code proved challenging. Different worktrees could share the same API, database, and services, leading to uncertainty about which code a browser test was actually using. This issue was particularly complex for changed API behaviors, experimental migrations, and parallel worker processes, which could alter test results.

This report moves the discussion from Git worktrees solving file conflicts to the more complex challenge of ensuring correct test environments for parallel development.