Jehu Amanna · Tinkerer
Computer programming notes from the workbench: small experiments, practical fixes, and things learned while taking software apart.
T–2026.09.07
Archive
Why the exact same regex pattern is instant in grep but can freeze JavaScript for minutes. - Study Notes
Building a working regex engine by hand, Thompson's construction, subset construction, and a linear-time matcher. - Study Notes
Why nondeterministic finite automata are no more powerful than DFAs, proved by subset construction. - Study Notes
Extending finite automata from yes/no acceptors into machines that act, using an elevator as the model. - Study Notes
A precise definition of "language" in computer science, and why JavaScript isn't a regular one. - Study Notes
Why a useState/useReducer component is, formally, a deterministic finite automaton. - Study Notes
Is it possible to review huge code output by AI for each prompt? - Study Notes