Projects · Code

Projects

Things I’ve built — tools, puzzles and open-source code.

Japanese · JLPT N2 · Free Nihongo A study site for the Japanese Language Proficiency Test — 66 grammar lessons that teach before they test, 1,023 kanji with the words you will actually meet, and timed reading and listening, all on spaced repetition. Free, and it works offline. Puzzles · Free · Works offline Logic Pad Grid logic puzzles, crosswords, codewords, nonograms, sudoku, hashi, word searches and word wheels — generated rather than stored, printable as books with the answers at the back. Plus 34 mysteries solved a chapter at a time. Open source · CC0 Erlang C, in every language The Erlang C call-centre staffing formula — a live calculator, the maths, and the same five functions written out in 30 programming languages. Free to copy, verified against known values.
Project musings
10 Oct 2026 A Galaxy for Dad My dad plays Dyson Sphere Program. If you haven’t met it: you land on a planet with a mech and a pickaxe, and some hundreds of hours later you are wrapping a star in a shell of solar sails to power a factory that spans d… 22 Sep 2026 Nine Kinds of Puzzle Logic Pad started as a brief I would have sacked a consultant for. Until today it made six kinds of puzzle. Now it makes nine. The new three are below. They are free like the rest, they need no sign-up, and they work wit… 11 Jul 2026 Staffing a call centre in Excel First in a short series: the same small staffing formula — Erlang C — written out one language at a time. We start where most of the world actually does this: in a spreadsheet.… 11 Jul 2026 Erlang C in Python Part of Erlang C, in every language — the same call-centre staffing formula, one language at a time. Here it is in Python: standard library only, nothing to pip install.… 11 Jul 2026 Erlang C in SQL Part of Erlang C, in every language. Sometimes the staffing calc belongs where the call data already lives — in the database. Here’s the whole thing as PostgreSQL functions.…