Learn Rust by Building a JSON Parser

Step 03 of the path · Intermediate to advanced · See all steps

Keep 90% of your Python. Own the 10% that matters.

The fast layer under your Python (ruff, uv, Pydantic, Polars) is Rust, and AI will happily generate more of it for you. The skill getting scarce is telling when that Rust is wrong. You learn it by building a real JSON parser from scratch, callable from Python, with every pull request reviewed by engineers who've shipped Rust in production.

Coached by Jim & Bob · meet your coaches ↓

Book a call to reserve your seat → Full curriculum →

What you walk away with

Judgment

Read real Rust and catch what AI gets wrong: the needless clone, the swallowed Result, the ownership model you couldn't defend.

A real artifact

A fast JSON parser on your GitHub, wired into Python with PyO3, the same FFI behind Pydantic and Polars.

Better Python

Explicit errors, no nulls, clear ownership. The precision carries straight back into your Python.

Rust JSON parser program overview

The artifact is real: Josh Engroff's parser, built from scratch in 6 weeks, beats CPython's stdlib json by up to 2.96× (benchmarks).

Code review, not "it compiles"

Every week you push code and your coaches review it, the way a Rust developer thinks. Click a screenshot to zoom in.

Code review on API design — API design: why `&[T]` beats `&Vec<T>` at a boundary

Code review on readability — Readability: flattening five levels of nesting, and the dialogue that follows

Code review on testing — Testing: stronger assertions, not tests written blindly

Code review on error messages — Error UX: a `Some(...)` wrapper leaking into a user-facing message

Code review on naming — Naming: descriptive over terse, the idiomatic Rust default

Code review on refactoring a loop — Refactoring: breaking a complex loop into focused methods

"Building something real made Rust click in a way that tutorials never could, and honestly, it's made me a better Python developer too."

— Vikas Z., Python to Rust in 6 weeks

"I left able to read real Rust, spot AI hallucinations, and apply the mental model at work. Great value for busy engineers."

— Tim F., Rust cohort

Join the cohort

€2,000 one-time · 6 weeks · ~10 hrs/week

Detailed PR review on every push: ownership, lifetimes, and idiomatic Rust
A 6-week curriculum from tokenizer to PyO3 bindings and benchmarks
Weekly group call with both coaches, recorded, plus async support
Capped at 6 developers, plus the Rust Never Sleeps Slack for peers and accountability, during and after
No Rust experience needed, just comfort in Python or another language

Book a call to reserve your seat →

Your coaches

Jim Hodapp: seasoned Rust developer, open source contributor, and software engineering coach with over two decades of experience, from GNOME and Ubuntu to embedded systems and startups.

Bob Belderbos: developer coach and builder, co-founder of Pybites, built its Python and Rust coding platforms. 150+ developers coached. Bob brings the Python side: PyO3, when to reach for Rust, and clean code in both languages.

Next on the path: 1:1 coaching on your own Rust or Python project.