Track per-user, per-project, and per-board usage to inform pricing tier
decisions. Adds an admin dashboard with KPIs (DAU/WAU/MAU, totals,
success rate), time-series charts for compiles/runs, board family +
FQBN breakdowns, "board diversity" pie chart (key freemium signal),
top users/projects, and per-country breakdown via Cloudflare's
CF-IPCountry header. Admin can now also view private projects.
Backend:
- New UsageEvent table (append-only event log with user_id, project_id,
event_type, board_fqbn/family, country, error_kind, duration_ms)
- Aggregate counters on User (total_compiles/runs/errors, last_active,
signup_country, last_country) and Project (compile/run/update counts,
last_compiled/run timestamps) kept in sync by MetricsService for O(1)
dashboard reads
- 10 admin endpoints under /api/admin/metrics/{overview, timeseries,
boards, board-diversity, top-users, top-projects, countries,
users/{id}, projects/{id}}
- POST /api/metrics/run for client-side run telemetry
- Country detection via cf-ipcountry header (no DB / no API calls)
- Auto-migrations in lifespan for legacy DBs
Frontend:
- recharts-powered Dashboard tab with KPI cards and 4 charts
- New Boards tab with per-family + per-FQBN breakdown
- Country column with flag emoji on Users tab
- Top countries card on Dashboard
- compileCode now forwards project_id; Run button reports via WS
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>