Overmatch

A tool for matching Overture Maps data with OpenStreetMap elements and applying enriched tags to OSM.

Overview

Overmatch helps OSM contributors improve map data by:

1. Matching OSM amenities (restaurants, cafes, bars, etc.) with corresponding Overture Maps data
2. Reviewing tag differences in a visual comparison interface
3. Applying enriched tags from Overture to OSM elements
4. Tracking which elements have been processed to avoid duplicate work

Architecture

The system consists of three components:

┌─────────────────┐
│  Matching       │  Python scripts for geospatial matching
│  Scripts        │  (OSM ↔ Overture)
└────────┬────────┘
         │ JSONL output
         ▼
┌─────────────────┐
│  Tracking API   │  FastAPI + DynamoDB on AWS Lambda
│  (FastAPI)      │  Tracks processed elements & stores matches
└────────┬────────┘
         │ REST API
         ▼
┌─────────────────┐
│  Web Frontend   │  React + MapLibre
│  (React)        │  Visual review and tagging interface
└─────────────────┘

Components

1. Matching Scripts (/scripts)

Python scripts that perform geospatial matching between OSM and Overture data:

• match.py: Core matching algorithm using spatial indexing and fuzzy name matching
• get_osm_ids.py: Fetches OSM elements for a given area
• build_query.py: Builds Overpass queries for OSM data
• get_categories.py: Analyzes Overture category distributions

Key features:

• Spatial indexing (R-tree) for efficient nearest-neighbor search
• Fuzzy name matching using RapidFuzz
• Configurable distance and similarity thresholds
• Outputs JSONL format with match metadata

Dependencies: GeoPandas, RapidFuzz, rtree, atlus, overturetoosm

2. Tracking API (/api)

FastAPI service deployed on AWS Lambda that tracks processed elements:

• GET/POST /osm: Track which OSM elements have been uploaded with changes
• GET/POST /overture: Track which Overture elements have been marked as non-matching
• GET /matches: Retrieve OSM-to-Overture matches from DynamoDB

Key features:

• Serverless architecture (Lambda + DynamoDB)
• Millisecond response times at any scale
• Timestamp tracking for audit trails
• Infrastructure as Code (CloudFormation)

Cost: under $5/month for moderate usage

See api/README.md for detailed deployment instructions.

3. Web Frontend (/front_end)

React application for reviewing matches and applying tags:

• Visual comparison table showing OSM vs Overture tags
• Interactive map with MapLibre GL
• Support for multiple Overture matches per OSM element
• Batch upload to OSM via authenticated changesets
• Automatic deduplication using tracking API

Key features:

• Color-coded tag differences
• Live OSM data fetching
• Relation-based area selection
• OAuth authentication with OSM
• Persistent state management (Zustand)

See front_end/IMPLEMENTATION_NOTES.md for implementation details.

License

Provided under the MIT License.

Contributing

Contributions welcome! Please ensure:

1. Matching scripts handle edge cases (nodes, ways, relations)
2. API changes are reflected in CloudFormation template
3. Frontend changes maintain TypeScript type safety

Support

For issues or questions, please open an issue on GitHub.