https://arxiv.org/abs/2011.07966 close this message arXiv smileybones icon Global Survey In just 3 minutes help us understand how you see arXiv. TAKE SURVEY Skip to main content Cornell University We gratefully acknowledge support from the Simons Foundation and member institutions. arxiv logo > cs > arXiv:2011.07966 [ ] Help | Advanced Search [All fields ] Search arXiv logo Cornell University Logo [ ] GO quick links * Login * Help Pages * About Computer Science > Programming Languages arXiv:2011.07966 (cs) [Submitted on 16 Nov 2020 (v1), last revised 25 Jan 2021 (this version, v3)] Title:A Modern Compiler for the French Tax Code Authors:Denis Merigoux (PROSECCO), Raphael Monat (APR), Jonathan Protzenko (MSR) Download PDF Abstract: In France, income tax is computed from taxpayers' individual returns, using an algorithm that is authored, designed and maintained by the French Public Finances Directorate (DGFiP). This algorithm relies on a legacy custom language and compiler originally designed in 1990, which unlike French wine, did not age well with time. Owing to the shortcomings of the input language and the technical limitations of the compiler, the algorithm is proving harder and harder to maintain, relying on ad-hoc behaviors and workarounds to implement the most recent changes in tax law. Competence loss and aging code also mean that the system does not benefit from any modern compiler techniques that would increase confidence in the implementation. We overhaul this infrastructure and present Mlang, an open-source compiler toolchain whose goal is to replace the existing infrastructure. Mlang is based on a reverse-engineered formalization of the DGFiP's system, and has been thoroughly validated against the private DGFiP test suite. As such, Mlang has a formal semantics; eliminates previous handwritten workarounds in C; compiles to modern languages (Python); and enables a variety of instrumentations, providing deep insights about the essence of French income tax computation. The DGFiP is now officially transitioning to Mlang for their production system. Subjects: Programming Languages (cs.PL) Cite as: arXiv:2011.07966 [cs.PL] (or arXiv:2011.07966v3 [cs.PL] for this version) https://doi.org/10.48550/arXiv.2011.07966 Focus to learn more arXiv-issued DOI via DataCite Submission history From: Denis Merigoux [view email] [via CCSD proxy] [v1] Mon, 16 Nov 2020 13:57:00 UTC (69 KB) [v2] Thu, 26 Nov 2020 10:53:30 UTC (69 KB) [v3] Mon, 25 Jan 2021 10:19:30 UTC (69 KB) Full-text links: Download: * PDF * Other formats (license) Current browse context: cs.PL < prev | next > new | recent | 2011 Change to browse by: cs References & Citations * NASA ADS * Google Scholar * Semantic Scholar DBLP - CS Bibliography listing | bibtex Jonathan Protzenko a export bibtex citation Loading... Bibtex formatted citation x [loading... ] Data provided by: Bookmark BibSonomy logo Mendeley logo Reddit logo ScienceWISE logo (*) Bibliographic Tools Bibliographic and Citation Tools [ ] Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) [ ] Litmaps Toggle Litmaps (What is Litmaps?) [ ] scite.ai Toggle scite Smart Citations (What are Smart Citations?) ( ) Code, Data, Media Code, Data and Media Associated with this Article [ ] Links to Code Toggle Papers with Code (What is Papers with Code?) [ ] ScienceCast Toggle ScienceCast (What is ScienceCast?) ( ) Demos Demos [ ] Replicate Toggle Replicate (What is Replicate?) [ ] Spaces Toggle Hugging Face Spaces (What is Spaces?) ( ) Related Papers Recommenders and Search Tools [ ] Connected Papers Toggle Connected Papers (What is Connected Papers?) [ ] Core recommender toggle CORE Recommender (What is CORE?) ( ) About arXivLabs arXivLabs: experimental projects with community collaborators arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website. Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them. Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs and how to get involved. Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?) * About * Help * Click here to contact arXiv Contact * Click here to subscribe Subscribe * Copyright * Privacy Policy * Web Accessibility Assistance * arXiv Operational Status Get status notifications via email or slack