A self-hosted FIRE and net-worth projection planner with a correct Dutch tax engine.
Most projection tools (ProjectionLab, Boldin) model US tax, and most portfolio trackers (Ghostfolio) don't project. Vuurtoren does both, for a Dutch household: Box 3 under the forfaitair regime and the Wet werkelijk rendement scheduled for 2028, the tegenbewijs, mortgage interest deduction net of the eigenwoningforfait and Wet Hillen, transfer tax with the starter exemption, and Box 3 split across fiscal partners. Every tax figure is dated and cites its source.
Your plan lives in a SQLite file on your machine. There is no account, no cloud and no subscription. The same Python engine also compiles to WebAssembly, so there is a zero-install browser build that runs entirely client-side: your household numbers never leave the page. Its only outside request is the Pyodide Python runtime, downloaded once from cdn.jsdelivr.net; the engine and its dependencies come from the site itself. You keep your work by exporting a JSON file and importing it back. Live price refresh is the one thing it can't do without a server.
Try the demo in your browser → It runs a made-up example household, and the first start downloads about 20 MB.
Requires uv, Python 3.14, Node 26 or newer and pnpm.
uv sync
pnpm -C frontend install
pnpm -C frontend build # build the UI into the app's static mount
uv run vuurtoren # serves the app at http://127.0.0.1:8000For a live-reloading UI, run uv run vuurtoren and pnpm -C frontend dev side by side.
The browser build is pnpm -C frontend build:browser, with static output in
src/vuurtoren/static. just --list shows the wrapped commands.
Start empty and create your household in the UI, or seed it from a TOML file:
mkdir -p data && cp household.example.toml data/household.toml # then add your holdings
uv run python -m vuurtoren.seeddata/household.toml is gitignored. Nothing about a real household is ever committed.
- CONTRIBUTING.md: the checks, the architecture rules, adding a country.
- CHANGELOG.md: what each release changed.
- docs/decisions.md: what was decided and why, including what is deliberately not built. The Plan surface lists the tax engine's known gaps.
- PRODUCT.md and DESIGN.md: who it is for and how it looks.
MIT.