Hands-on study tools where you debug real snippets, get instant verification, and learn the rule behind every trap.
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Fix buggy snippets from the Oracle Certified Professional exam: operators, control flow, classes and the traps examiners love.
Start JavaFunctional programming with Clojure, based on Brave Clojure: syntax, data structures and core functions in depth.
Start ClojurePractical Python based on Automate the Boring Stuff — buggy-code challenges with a sandboxed runner.
Start PythonBuild a real project, one lesson at a time.
Build the classic Nokia Snake game step by step. 28 hands-on lessons in a live editor, with your progress synced to your own GitHub repo.
Start buildingRebuild the legendary HP-12C in Python — TVM, cash flow, amortization, depreciation, dates and stats. 24 test-gated lessons (in Portuguese), run live with Pyodide and synced to your GitHub repo.
Start buildingStart free. Upgrade once, keep it forever.