Athlete Pro — Offline-First Workout Tracker + AI Coach

Privacy-first PPL workout tracker built as an installable PWA. Your training data lives on your device (IndexedDB, airgap mode by default) — the cloud is optional, the AI coach is bring-your-own-key.

Live: athlete-pro-v7.vercel.app

Why it's different

• Offline-first, privacy tri-state — airgap (default, data never leaves the device), anon, or cloud. Sync is opt-in, powered by an LWW sync engine.
• BYOK AI Coach — plug in your own Anthropic or Gemini API key; streaming responses over SSE, keys handled server-side only, never shipped to the frontend.
• Zero frameworks — hand-tuned Vanilla JS (ES Modules), Store/View architecture, spring-physics animations, GPU-only transforms. Lighthouse 97, WCAG AA.

Features

• PPL workout logging with a 170-exercise library and drum-style set logger
• Dynamic Island status bar: live session tracking, rest timer, sync indicator
• Analytics: 1RM estimation, DOTS score, PR history, muscle fatigue heatmap
• Cycle plans with exercise aliasing (rename lifts without losing weight history)
• Body stats, 3-step onboarding with fast skip
• Installable PWA: Service Worker precache, self-hosted fonts, works fully offline

Quick Start

npm install
cp .env.example .env       # fill in ANTHROPIC_API_KEY (optional — only for AI coach)
npm run dev                 # http://localhost:3000

Tech

• Frontend: Vanilla JS (ES Modules), no frameworks. Store/View split per module.
• Backend: Express (ESM) — helmet + CSP, compression, rate limiting, zod validation.
• Storage: IndexedDB (offline-first) + optional Supabase cloud sync.
• AI: lib/aiOrchestrator.js — multi-engine (Anthropic / Gemini), BYOK, SSE via POST /api/coach.

Env Variables

Variable	Required	Purpose
ANTHROPIC_API_KEY	For AI coach	POST /api/coach
PORT	No (default 3000)	Server port
SUPABASE_URL	No	Cloud sync
SUPABASE_ANON_KEY	No	Cloud sync

Tests

npm test                # unit + integration (node --test)
npm run test:e2e        # Playwright e2e

Docs

• CLAUDE.md — dev guide for Claude Code
• CLAUDE.md § Design — design system spec (OLED near-black, glassmorphism, token palette)
• docs/ROADMAP_elite_athlete-pro.md — roadmap
• CHANGELOG.md — version history
• docs/ — everything else: RULES, CONTRIBUTING, DEPLOYMENT, THREAT_MODEL
• docs/handoff/ — active handoffs (CLAUDE.md § «Где что лежит» for the layout rule)