🧭 OSS Learning Path — From 0 to Defending My Contributions

Who this is for: me. I made real open-source contributions (12 merged into HuggingFace hub/accelerate/peft, pydantic, marimo, mem0, unsloth, xorbitsai/inference, agno; open PRs to vLLM, Microsoft autogen, OpenAI, litellm; built a static analyzer called codehound). This repo explains every single concept behind that work, from absolute zero, so I can understand and defend it — in interviews, in conversations, in my own head.

How to read it: top to bottom, in order. Each file builds on the last. Every term is defined the first time it appears. Nothing is assumed.

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The path (read in this order)

01 — Foundations (what even is open source?)

• 01_foundations/01_git_and_github.md — git, commit, branch, remote, fork, clone, push, pull
• 01_foundations/02_what_is_a_pull_request.md — PR, merge, review, CI, the whole flow
• 01_foundations/03_open_source_glossary.md — maintainer, upstream, CLA, issue, "good first issue", stars

02 — Python you need to understand the bugs

• 02_python/01_how_python_runs.md — interpreter, modules, imports, the call stack
• 02_python/02_functions_args_defaults.md — arguments, defaults, the mutable-default trap (your B006 fixes)
• 02_python/03_files_and_resources.md — file handles, open, with, what "leaking" means (your file-handle fix)
• 02_python/04_the_ast.md — what an Abstract Syntax Tree is (the heart of codehound)

03 — Async Python (most of your bugs live here)

• 03_async/01_what_is_concurrency.md — concurrency vs parallelism, the event loop
• 03_async/02_asyncio_basics.md — async/await, coroutines, tasks
• 03_async/03_blocking_the_loop.md — why time.sleep/requests in async is a disaster (agno #8158, #8186)
• 03_async/04_fire_and_forget_tasks.md — weak references, garbage collection, dropped tasks (OpenAI #3553, litellm #29417, agno #8183)

04 — Your actual bugs, explained one by one

• 04_the_bugs/README.md — every merged/open PR, what it was, why it mattered, in plain English

05 — The tooling you used

• 05_tooling/01_codehound_how_it_works.md — your own tool, explained as if you're learning it fresh
• 05_tooling/02_testing_and_ci.md — pytest, regression tests, ruff, GitHub Actions

06 — Quick reference

• 06_reference/interview_cheatsheet.md — 60-second answers to "explain X"
• 06_reference/glossary.md — every term, one-line definition, A–Z

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How to use this in an interview

When someone asks "tell me about your open-source work," you don't recite — you explain the bug. Every file here ends with a "Say this in an interview" box: the exact 2–3 sentences that show you understand it. Learn those, understand the rest, and you'll out-explain people who've been coding for years.