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The mapTax authorityPolicy, Legislation & Revenue Analysis
Rules as code & legislative drafting
covered · 7 open projects
Writing legislation and guidance so it can be tested and run, next to the legal text it implements.
Start with
Catala writes the statute article by article next to the law; OpenFisca serves a country's rules as an API. Pick by how close to the legal text you must stay.
Its 7 projects
| Project | Kind | Jurisdiction | Last update | Stars |
|---|---|---|---|---|
| CatalaProgramming language for writing law as code, next to the legal text it implements. | Tax engines | Global · FR | Oct 2026 | 2.4k |
| OpenFiscaRules-as-code framework: legislation written in Python, served as a web API. | Tax engines | FR · Global | — | — |
| ALEF (Belastingdienst)Dutch Tax Administration tool for writing executable tax rules in RegelSpraak without programming. | Tax engines | NL | Sep 2026 | 29 |
| IRS Fact GraphKnowledge-graph rules engine that models the US Internal Revenue Code, the calculation core of Direct File. | Tax engines | US | Sep 2026 | 419 |
| MlangCompiler for DGFiP's M language, used to compute the income tax of French taxpayers. | Tax engines | FR | Jan 2026 | 203 |
| OpenFisca AIGuides, validation tools and agent scaffolding for building OpenFisca country packages. | Agent skills | Global | Apr 2026 | — |
| OpenFisca Polynésie françaiseFrench Polynesia's tax system as OpenFisca rules-as-code. | Tax engines | PF | Jun 2026 | — |
Every project here is maintained and serves a tax authority. See the team's projects in the list.
On Learn
- Rules as codeGlossary term
- Agent skillGlossary term