Bankroll40 docs

The product spec, the architecture decisions and the record of how each changed. Everything here is a file in the docs repository; this site is built from the main branch on every merge.

• Product spec 0.7 · 2026-10-02 · revised in place; history on the [versions page](/versions/)
• Acceptance contract, phase 1 2 · 2026-10-02 · the criteria the phase 1 build is judged against; each names its evidence
• Release spec v0.1.0 2 · 2026-10-02 · what ships first, what waits, and how we know it is done
• Growth simulation 1 · 2026-10-02 · a Monte Carlo of one year of play, 20,000 runs per policy; code in `spec/figures/sim/sim.ts`
• Architecture decision records 6
• Versions