GitHub Quickstart
license:Apache-2.0 tiers:0 demo-wall:none

Start expressing your data.

Semantic Rails ships as an Apache-2.0-licensed repo. Read the source, run the quickstart, or run the comparison pack against other semantic layers. See License for the full terms.

START

Read the source

semantic_rails/mcp.py, semantic_rails/planner/plan.py, semantic_rails/compiler.py, and semantic_rails/http_core.py are the runtime surface to inspect first.

RUN

Run the quickstart

Install with uv, validate the Jaffle package, start the MCP server against a local DuckDB. Less than ten minutes.

EVALUATE

Run the comparison pack

Same 16 questions, five layers, executed against the same shared dataset. See where each layer pays for a workaround vs. a governed primitive.

What's in the repo

  • Agent runtime + MCP server (stdio + HTTP).
  • Authored Jaffle reference package + Snowflake TPC-H showcase.
  • Dated comparison pack against four other semantic layers.
  • CLI: parse-config, validate-config, test-package.

What's not in the repo

  • Hosted multi-tenant cloud or managed service.
  • General ELT or pipeline orchestration.
  • BI tool or dashboarding layer.
  • Materialization / caching layer (execution is the warehouse's job).

Common questions.

Yes. Apache 2.0 permits broad commercial use, modification, and distribution, and includes an express patent grant when the copyright and license notice are retained.
No. The Jaffle reference package runs locally against DuckDB. Snowflake works through the Snow CLI or the native connector when you have a connection configured, and the other supported warehouses connect the same way.
Not at this time. The repo ships the runtime; deployment is the operator's job.
GitHub Issues, with the repro template in SUPPORT.md. Security reports go through the private path in SECURITY.md.