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Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works
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Unsafe or Not?

Four lines, one spot, and only one needs an unsafe block. Raw pointers made or followed, static and static mut, unions written or read, unsafe fn calls, leaks.

🎯 5 in a row 🚫 no clock
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