How CPython Tests Make PyTorch Dynamo Better | Guilherme Leobas | PyTorch Conference 2025

Guilherme Leobas, Software Engineer at OpenTeams, walks through his PyTorch Conference 2025 poster: “Breaking Glass: Tackling Graph Breaks with CPython Tests.” Dynamo is the symbolic tracer that runs first when you use torch.compile. To check that Dynamo is correct, Guilherme ran it against CPython’s own test suite. The team started with 36 test files and more than 2,600 test cases. Passing tests grew from 20% to around 40%. Along the way, Dynamo gained full support for generators and context managers, correct exception handling, better support for dictionaries and sets, and four new opcodes. Guilherme returns to PyTorch Conference North America 2026 with a new poster, “Mirroring CPython’s Object Protocol in Dynamo.” Find him on Oct 20, 6:00 to 7:30 pm, at the Community Expo. 👉 Follow OpenTeams on LinkedIn: https://www.linkedin.com/company/openteams 🔔 Subscribe for more open source and AI talks #PyTorch #Python #OpenSource