A federated fitness tracking platform built on ActivityPub, using Quarkus and Vert.x. Share your runs, rides, and activities across the fediverse while maintaining ownership of your data.
Open Pace is a federated alternative to Strava that:
- ✅ Lets you own your data (run your own instance or choose one you trust)
- ✅ Works with the fediverse (Mastodon users can follow your activities)
- ✅ Supports rich sports data (GPX, metrics, segments, leaderboards)
- ✅ Maintains privacy (you control who sees what)
- ✅ Enables data portability (export anytime, move instances)
This project is structured as 10 implementation sprints that build a complete federated ActivityPub application incrementally.
Goal: Get federation working end-to-end
- WebFinger for user discovery
- Actor profiles with ActivityPub endpoints
- Simple text posts
- Test by following from Mastodon
Status: 🚧 In Progress
Tag: v0.1.0-sprint1 (when released)
Goal: Extend ActivityPub with sports-specific data
- Define Run/Walk/Ride/Swim object types
- Handle custom
Createactivities - Store GPX data and metrics
- Render activities in your UI
Status: 📋 Planned
Tag: v0.2.0-sprint2 (when released)
Goal: Make it beautiful and interoperable
- Handle comments/likes from any ActivityPub server
- Full activity viewer for FediRun clients
- Attachments support (images, previews)
- Activity streams (your feed, following feed)
Status: 📋 Planned
Tag: v0.3.0-sprint3 (when released)
Goal: Strava-like competitive features
- Segment tracking (like Strava KOMs)
- Leaderboards across federated instances
- Clubs/groups (ActivityPub Groups)
- Challenges and goals
Status: 📋 Planned
Tag: v0.4.0-sprint4 (when released)
Goal: Production-ready privacy and data control
- Private activities (only to followers)
- Direct messages for training partners
- Export your data anytime (GPX, FIT files)
- Instance-level federation policies
Status: 📋 Planned
Tag: v0.5.0-sprint5 (when released)
Goal: Authentication and authorization
- User registration and login
- Password hashing (BCrypt)
- Secure C2S endpoints (only actor can post to their outbox)
- Verified field for future email verification
- Actor-User relationship
Status: 📋 Planned
Tag: v0.6.0-sprint6 (when released)
Strategy: Security Integration Guide
Goal: Geospatial data and map visualization
- GPX processing and track extraction
- PostGIS storage (LineString for tracks)
- Generate static map images with tracks overlaid on OpenStreetMap tiles
- Proper OSM attribution on all maps
- Display maps in ActivityPub activity attachments
Status: 📋 Planned
Tag: v0.7.0-sprint7 (when released)
Strategy: Mapping Integration Guide
Goal: Advanced analytics and personal record tracking
- Automatic personal record detection (fastest 5K, longest ride, etc.)
- Split analysis (per km/mile)
- Pace zones and heart rate zones
- Elevation profile visualization
- Comparative analysis (this run vs. average)
- Activity statistics dashboard
Status: 📋 Planned
Tag: v0.8.0-sprint8 (when released)
Technical:
- Time-series data analysis
- Efficient queries for PRs across all activities
- Chart generation (Recharts in React)
- Database indexes for performance queries
Goal: Social features and activity feed
- Activity feed (timeline of followed users)
- Comments on activities (ActivityPub replies)
- Kudos/Likes (ActivityPub Like activities)
- Activity sharing to feed
- @mentions in comments
- Notifications for interactions
Status: 📋 Planned
Tag: v0.9.0-sprint9 (when released)
Technical:
- ActivityPub Create/Like/Announce activities
- Feed aggregation and ranking
- Real-time notifications (WebSocket or SSE)
- Efficient timeline queries
Goal: Track equipment usage and maintenance
- Add bikes, shoes, other gear
- Track mileage/usage per gear
- Assign gear to activities (retroactively)
- Maintenance reminders
- Gear retirement tracking
- Default gear per activity type
Status: 📋 Planned
Tag: v1.0.0-sprint10 (when released)
Technical:
- Gear database schema
- Activity-gear relationship
- Aggregation queries for mileage
- Scheduled notifications for maintenance
- Java 21+ (LTS)
- Maven 3.8+
- Podman (for Quarkus Dev Services)
- Basic understanding of REST APIs
This project uses a single, evolving codebase where each sprint builds incrementally on the previous one. Git tags provide access to the state of the codebase at each sprint completion.
Repository Structure:
src/main/java/org/openpace/- Source code (packages added incrementally per sprint)src/test/java/org/openpace/- Testsdocs/- Implementation guides and strategy documentspom.xml- Single Quarkus project configuration
Accessing Previous Sprint States:
# View Sprint 1 code
git checkout v0.1.0-sprint1
# View Sprint 2 code
git checkout v0.2.0-sprint2
# Return to latest development
git checkout develop-
Clone and checkout the sprint you want to work with:
git clone <repository-url> cd open-pace # For Sprint 1 git checkout v0.1.0-sprint1 # Or work on latest development git checkout develop
-
Start the application (database starts automatically via Quarkus Dev Services):
./mvnw quarkus:dev
Quarkus Dev Services will automatically:
- Start a PostgreSQL container
- Configure the database connection
- Run Flyway migrations
-
Implement or extend sprints:
- Follow the implementation guide in
docs/ - Build on existing codebase
- Test with Mastodon
- Follow the implementation guide in
- Implementation Strategy: Overall approach, principles, structure, and workflow for implementation sprints
- Consistency Checklist: Quality standards for each sprint
- Quarkus Tech Stack:
⚠️ Technology choices, dependency philosophy, and why Quarkus - Read this before suggesting technology changes
- Database Design: Schema design, indexing, and query patterns
- API Design: ActivityPub vs Application endpoint organization, OpenAPI documentation
- Error Handling Strategy: Validation and error response format
- Federation Delivery Strategy: Reliable activity delivery with retry and queue management
- Caching Strategy: Multi-level caching (L1: memory, L2: Redis, L3: disk)
- Rate Limiting Strategy: Abuse prevention and resource protection
- Background Job Processing Strategy: Asynchronous job processing with Redis queues
- HTTP Signatures Strategy: S2S authentication for ActivityPub federation
- Architectural Gaps: Analysis of missing architectural elements
- ActivityPub C2S Pattern: Correct client-to-server implementation
- Mapping Integration: OpenStreetMap and geospatial data strategy
- Security Integration: Authentication and authorization strategy
- Sprint 1 Implementation: Start here!
- Product Backlog: Feature ideas, future sprints, and roadmap
- Quarkus: Java framework optimized for cloud-native
- Vert.x: Async, non-blocking processing (perfect for GPX processing, map generation)
- PostgreSQL: Data storage
- ActivityPub: W3C standard for federated social networking
See Quarkus Tech Stack for detailed versions and technology choices.
- Async GPX processing: Parse large files without blocking
- Map tile generation: Generate images efficiently
- Efficient federation: Deliver activities to many followers
- WebSocket support: Live activity tracking
- Non-blocking I/O: Handle webhook-style inbox POSTs
Each tutorial part includes:
- Unit tests for business logic
- Integration tests for ActivityPub endpoints
- Manual test scripts (curl commands)
- Mastodon compatibility testing
Run tests:
./mvnw testWe welcome contributions! Please read our Contributing Guide for details on:
- How to contribute (including AI-assisted contributions)
- Code standards and review process
- Git workflow and branch naming
- What to contribute and priorities
Quick start: Fork the repo, create a feature branch from develop, make your changes, and submit a Pull Request.
This project is licensed under the Apache License 2.0 - see the LICENSE file for details.
Apache License 2.0 allows you to:
- ✅ Use the software commercially
- ✅ Modify and distribute
- ✅ Patent use
- ✅ Private use
- ✅ Sublicense
Requirements:
- 📋 Include license and copyright notice
- 📋 State changes if you modify files
- 📋 Include NOTICE file if present
For full license terms, see LICENSE.
When you post a run on Open Pace:
- Your server creates an ActivityPub
Createactivity - The activity is sent to all your followers' inboxes
- Mastodon users see: "Alice ran 5km in 25:30" (rendered as a post)
- FediRun users see the full activity with map, splits, heart rate
- Anyone can like or comment from their ActivityPub server
This is the power of federation: interoperability without centralization.