Finalize Node.js Time Tracker

I have a nearly completed employee-time-tracking app built with Node.js and the Vibe Coding stack. Before we can release it internally, a few stubborn bugs are undermining time-logging accuracy. I need an experienced Node.js developer to jump in, hunt down the miscalculations, and deliver a clean, reliable fix.

Scope
• Diagnose and resolve the bug(s) causing incorrect or missing time entries.
• Review the existing codebase for any logic that could create drift between start/stop events and the final totals.
• Add concise unit or integration tests that prove the calculations now behave as expected across typical edge cases (overnight shifts, rapid clock-ins, etc.).
• Walk me through the changes in a brief hand-over so I understand what was patched.

Tech snapshot
Node.js, Express, MongoDB, Vibe Coding framework and a lightweight front-end built in vanilla JavaScript.

Deliverables
1. Patched source code pushed to our private Git repo.
2. Test suite demonstrating accurate logging.
3. Short change-log / read-me summarizing fixes.

If you’ve squashed similar time-tracking bugs before and can turn this around quickly, I’d love to work with you.