Add a Monte-Carlo "FIRE number" solver so the wealth dashboard can show a £ countdown to retirement across life-stage cases, in today's money. Viktor wants to see, per country, how far his net worth is from being able to retire for good under three cases — Solo (his spend ×1.5), Household (+Anca ×1.5), Family (+2 kids) — with cost-of-living re-scaling per country and a 99% Guyton-Klinger success bar. - spend_model: per-Case real-GBP spend, COL-scaled (rent + non-rent essentials scale by country; Holidays fixed), ×1.5 safety. Constants sourced live from actualbudget (Viktor) / on-record (Anca). - geo: city -> tax jurisdiction (nomad fallback). - fire_target: binary-search the smallest LIQUID net worth where GK reaches the bar; pension modelled as a tranche unlocking at ~57, kids ramp + optional home as cashflows. New fire_target table (migration 0007) + idempotent upsert. - recompute-fire-targets CLI: solve every Case x country and persist for Grafana. - CONTEXT.md glossary + ADR-0001 (why MC-threshold on liquid NW, not 25x spend). Reuses the existing simulator unchanged (its cashflow hooks already supported pension/kids/home). 345 tests pass; mypy + ruff clean. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
1.7 KiB
FIRE Planner — Context
A personal FIRE engine: a Monte-Carlo retirement-success simulator plus a live "can I retire yet?" countdown that tracks net worth against per-life-stage targets.
Language
Case: A named life-stage the countdown tracks. Solo (Viktor only), Household (Viktor + Anca), Family (Household + 2 kids). Each Case is a real-GBP annual spend. Avoid: scenario (reserved for the Cartesian simulator row — jurisdiction × strategy × leave-year × glide).
FIRE number / Target NW: The smallest liquid net worth (real GBP, country-specific) at which a Case's Guyton-Klinger plan reaches the bar. Computed by Monte-Carlo threshold, not a fixed SWR multiple. Avoid: goal, magic number, the number.
The bar: The Monte-Carlo success probability that counts as "can retire" — 99%.
Countdown: Target NW − current liquid NW, in real GBP (today's money). Rendered with progress %, projected date, and runway.
Bridge pot / liquid NW: Assets spendable before the workplace pension unlocks (~57). Funds the early sequence-risk years. The pension is excluded from it and modelled as a tranche that joins later. Avoid: net worth (which includes the locked pension).
COL-driven spend: Spend that re-scales by a country's cost of living — rent (by 1-bed rent ratio) and non-rent essentials (by the no-rent basket ratio), plus kids' costs. Contrast: Fixed spend — Holidays, globally priced, unchanged by country.
Safety multiplier: The ×1.5 padding Viktor applies on top of measured real spend.
Re-entry trigger: The written rule — take paid work if the portfolio is below £1.0M for two consecutive quarters. A guardrail, surfaced on the dashboard, not a failure.