Lohnt sich dein eigenes Darwinbox?

Build a self-hosted internal HR record app for a small team. Not payroll, not compliance, just records and leave.

Stack, no substitutions:
- Next.js 15, App Router, TypeScript, Tailwind.
- SQLite via better-sqlite3, file at ./data/hr.db, schema created on first run.
- No auth provider, no cloud, no telemetry. Single shared password from HR_PASSWORD in .env, checked in middleware, plus an ADMIN_EMAILS list in .env that unlocks admin views.

In scope:
1. Employees table: name, work email, job title, department, manager (self-referencing), start date, employment type, location, status (active, on leave, exited), notes. Full CRUD for admins, read-only directory for everyone.
2. Org chart rendered from the manager field as nested lists, no graph library.
3. Leave: policies table (name, days per year, carry-over cap), balances computed per employee per calendar year, requests with start date, end date, half-day flag, reason, status (pending, approved, rejected).
4. Approval flow: a request goes to the employee's manager, manager sees a queue, approve or reject with a comment. Every state change writes an append-only audit row with actor, timestamp and old/new values.
5. Working-day math that skips weekends and a holidays table admins can edit. Store all dates as ISO strings, no timezone conversion.
6. Reports: leave taken per employee per year, headcount by department, and a CSV export of employees plus approved leave for whoever actually runs payroll.
7. Seed script with 12 fake employees, 2 policies and a few requests so the app is not empty on first load.

Out of scope, do not build: salary fields, payslips, tax logic, expenses, recruitment, performance reviews, mobile apps, email sending, any integration.

Deliverables: working app on npm run dev, npm run seed, a .env.example, and a README that states plainly that this is a record keeper and that payroll and statutory filing are handled by a human accountant outside this system.