Exercises

# curated build projects that drill the fundamentals concepts hands-on.

❯ cat documents/

DST-safe scheduler — subject Subject 2026-08-09
The work statement for a hand-built scheduling core — RFC 3339 parsing rules, the instant/civil/zoned type contract, gap and overlap resolution policies, the tzdb-update drill, and the hostile-zone acceptance fixtures.
DST-safe scheduler Exercise 2026-08-09
Hand-parse RFC 3339, model instant vs. civil time with explicit gap/overlap handling, store a future meeting that survives a tzdb update, and expand "daily at 2:30" across both DST edges.
UTF-8 codec + text-processing CLI Exercise 2026-08-08
Encode and decode UTF-8 by hand from the spec, then build a small text CLI on top — the bytes/code-points/graphemes tower turned into working code.
UTF-8 codec + text-processing CLI — subject Subject 2026-08-08
The work statement for a hand-rolled UTF-8 encoder/decoder from RFC 3629 plus a layer-aware text CLI — byte-pattern rules, the invalid sequences to reject, and test cases from é to the family emoji.