Cerridwen

Cerridwen provides geocentric planetary data suitable for a broad spectrum of astronomical and astrological applications, with a focus on the solar system and the bodies/points commonly used in astrology.

Among its features:

• Sun, Moon, the eight major planets, lunar nodes, Black Moon Lilith, Chiron, the four major asteroids (Ceres, Pallas, Juno, Vesta), and a curated set of fixed stars (Sirius, Vega, Spica, Regulus, Algol …).
• Tropical or sidereal zodiac with selectable ayanamshas (Lahiri, Krishnamurti, Fagan-Bradley, Raman, Yukteshwar, Djwhal Khul, J2000, galactic-center, …).
• 18 supported house systems (Placidus, Koch, Whole-sign, Porphyry, Regiomontanus, Campanus, Equal, Vehlow, Morinus, Topocentric, Alcabitius, APC, Meridian, Horizon …).
• Eclipse predictions, instantaneous aspect grids, transit-to-natal aspect lookup with applying/separating tags, solar/lunar/planetary returns, void-of-course Moon, lunation number, and a sqlite-backed events database with an iCal feed.
• Traditional technique endpoints for midpoints, antiscia, decans, terms, triplicity rulers, receptions, planetary hours, Hellenistic lots, profections, Zodiacal Releasing, cardinal ingresses, lunations, heliacal rising, and combined natal charts.
• Time-zone-aware date input via IANA names (Europe/Berlin etc.).

This repository hosts the Rust port. The original Python package was retired; the Rust crate under rust/ is API-compatible at the data shape level and ships substantially more.

Quick start

cd rust
CERRIDWEN_EPHE_PATH=$(pwd)/../sweph cargo run --features server --bin cerridwen-server

then open http://127.0.0.1:2828/ in a browser.

Components

• HTTP/JSON server — every feature exposed as REST endpoints under /v1/… plus /openapi.json + Swagger UI at /docs.
• Tabbed web console at /app — comprehensive in-browser interface covering every endpoint, with deep-linkable tabs, a chart wheel, and live SSE position streams.
• CLI ``cerridwen`` — prints sun/moon/lunation/VoC/next-event for the current moment.
• MCP server ``cerridwen-mcp`` — Model Context Protocol over stdio, letting LLM agents (Claude Code, IDE clients) call cerridwen as a tool.
• Event generator ``cerridwen-event-generator`` — populates a sqlite events table that the /v1/events and /v1/events.ics endpoints query.

See rust/README.md for full build/usage instructions and the API reference.

License

Cerridwen itself is MIT. Swiss Ephemeris is dual-licensed; the bundled libswisseph-sys ships the AGPL-3.0 variant, so the combined binary is AGPL-3.0 unless you license Swiss Ephemeris separately.