Two fixes:
(1) Simulator: portfolio drain is now `w + tax(w)`, not just `w`.
The pre-2026-05-10 engine recorded tax in tax_hist but never
subtracted it from the portfolio, so changing jurisdiction only
moved the median_lifetime_tax cell — the fan chart, success
rate, and ending percentiles were identical for UK vs Cyprus
vs Malaysia. (The PLAYBOOK_VIKTOR.md memo from 2026-04-26
explicitly noted this: "Success rate is regime-independent…
tax doesn't drain the portfolio in this simulator.")
Mental model now: spending_target is what the user takes home;
the tax bill is an additional drag on the same pool. Higher-tax
jurisdictions therefore drain faster and lower the success
rate, which is the user's intuition. Trinity 4% effectively
becomes "4% take-home + tax overhead". 188 tests still pass —
most use Malaysia (0%) or hit the regime-independent code paths.
(2) /what-if and /scenarios/new now pre-fill nw_seed_gbp from
GET /networth on first mount (when the wealthfolio_sync mirror
has data), so opening the form starts from the user's real
portfolio total instead of the £1.5M placeholder. Once the user
edits the field, subsequent NW refetches don't clobber it
(nwAutoFilled latch).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Until now life events were stored but ignored by the engine — pure
metadata. Now they actually move portfolios.
Engine:
- simulator.simulate() takes optional cashflow_adjustments: a (n_years,)
real-GBP array applied each year *after* savings + return but
*before* withdrawal. Positive = inflow, negative = outflow.
- New fire_planner/life_events.py with EventInput dataclass +
events_to_cashflow_array(events, horizon). Handles ranged deltas,
one-time amounts, disabled events, year clipping past horizon,
negative year_start (clipped to 0), and summing multiple events.
API:
- /simulate accepts optional life_events list. Server converts each
to EventInput, builds cashflow_adjustments, passes to simulate().
- Frontend Run-now on scenario detail now fetches the scenario's
life events and includes them in the request — projections finally
reflect "retire at 50, kid born at y3, inheritance at y22".
Tests: 11 events helper + 4 end-to-end engine + 1 API integration =
16 new tests. 188 total (was 172). mypy strict + ruff clean.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
