A single-screen personal dashboard (PWA) that consolidates workout logging, habit tracking, and everyday context into a unified interface. Built for daily personal use with zero ads, tracking, or data monetization.

Why

It started with a simple thought: why keep logging workouts in a phone’s notepad when I could build a tailored application around it and use the data to visualize strength progression and weight trends. I also wanted to explore AI coding agents in practice while creating something I use every day.

System Architecture

The dashboard aggregates direct user input stored in Supabase alongside automated background integrations from various public APIs:

┌─────────────────────────────────────────────────────────────────────────┐
│                      PERSONAL DASHBOARD (PWA)                           │
│             Next.js 15 · React 19 · Tailwind CSS · Vercel               │
└─────────────────────────────────────────────────────────────────────────┘
                     │                                   │
         [ Personal Logs & State ]              [ Automated APIs ]
                     │                                   │
      ┌──────────────┴──────────────┐     ┌──────────────┴──────────────┐
      │                             │     │                             │
┌─────▼────────┐              ┌─────▼───┐ ├─► Weather (Open-Meteo)
│ Workouts     │              │ Mood    │ │   Free weather API via browser location
│ (Gym / Run)  │              │ Books   │ ├─► Electricity Spot Prices (spot-hinta.fi)
│ Weight       │              └─────┬───┘ │   Finnish hourly spot pricing (incl. VAT)
└─────┬────────┘                    │     ├─► Flag Days (Ministry of the Interior)
      │                             │     │   Conditional display on official dates
      └──────────────┬──────────────┘     ├─► Music Stats (Spotify + Last.fm + Apple)
                     │                    │   Scrobbles, listening time, and genres
               ┌─────▼──────┐             └─► Homelab (HP EliteDesk)
               │  SUPABASE  │                 Host status over tunnel (offline)
               │ PostgreSQL │
               │ Auth + RLS │
               └────────────┘

Modules & Data Sources

Workouts & Strength Progression

• Functionality: Replaces workout notebooks. Supports training splits (Push / Pull / Legs / Upper / Run) with automatic saving per set.
• Data Source: Supabase PostgreSQL (workout_sessions, session_exercises, workout_logs).
• Progression Metric: Tracks estimated 1-rep max (e1RM) using the Epley formula. Charts register progressive overload immediately when reps increase, even if the bar weight remains constant.

Weight & Composition Tracking

• Functionality: Daily morning weight and calorie tracking.
• Data Source: Supabase (health_logs).
• Trend Analysis: Smooths out daily water weight fluctuations (1–2 kg) using a rolling calendar-week average to display a consistent weekly rate of change across the dashboard.

Music & Listening Analytics

• Functionality: Shows top artists, tracks, total listening hours, and album art across 7 days, 1 month, 6 months, and 1 year.
• Data Source: Spotify scrobbles background data to Last.fm. The dashboard queries the Last.fm API to compute exact listening duration, with genres matched via the Apple Music Search API.

Electricity Spot Pricing

• Functionality: Displays Finnish hourly electricity spot prices with current-hour highlighting and dynamic threshold coloring (green $\le$ 10 c, orange < 20 c, red $\ge$ 20 c/kWh).
• Data Source: spot-hinta.fi REST API.

Weather

• Functionality: Local temperature, wind, precipitation, weather icons, and sunrise/sunset times.
• Data Source: Open-Meteo API. Location is cached in localStorage for instant loads without repeated browser geolocation prompts.

Flag Days

• Functionality: Explains the occasion whenever flags are flying in Finland.
• Data Source: Official Finnish flag days implemented directly in client calendar logic (lib/flag-days.ts). Only rendered when today is an active flag day.

Mood Tracking

• Functionality: Daily rating (1–5) visualized as a GitHub-style activity heatmap.
• Data Source: Supabase (mood_logs).

Reading Log

• Functionality: Tracks active and completed books alongside page counts.
• Data Source: Supabase (books).

Homelab Telemetry

• Functionality: Quick status glance at home server resources (CPU, RAM, storage, running containers like Home Assistant / Immich).
• Data Source: Local HP EliteDesk mini-PC through a secure Tailscale / Cloudflare tunnel (falls back to “Offline” when the tunnel is down).

Tech Stack

Security & Architecture Notes

This is a single-user personal application, not a multi-tenant production product. Security is enforced at the infrastructure level:

• Authentication & Data Isolation: Supabase Auth with Row Level Security (RLS) policies applied to all personal tables.
• Secrets: API keys and credentials are restricted to environment variables (.env.local).
• Localization: Supports EN / FI language toggling with preference stored in localStorage.