# sim

Simulations of Igneum consensus rules. One script per rule, results next to it.

## finality_sim.py

Simulates the sustained-mining finality vote-weight rule: each key's weight is the sum over
the trailing 30 days of its counted blocks, where a day's counted blocks are capped at
2x the previous day's counted blocks plus a floor f. A checkpoint locks at two thirds of
total weight. Scenarios A to F (steady state, rental burst, key splitting, honest growth
shock, churn, patient owner) are described in `results.md` together with the model's
assumptions and the measured numbers.

Requirements: Python 3, numpy (checked present: 3.10.10, numpy 2.2.6 on 3 October 2026).

Run everything (about one second):

    python3 finality_sim.py > out.md

Options:

    --seed N          random seed, default 7 (seed 11 gives the same crossing days)
    --scenarios A,B   subset of A,B,C,D,E,F
    --floors 1,10     floor values in blocks per key per day, default 1,10,100,1000
    --growth 2.0      daily cap multiplier (1e9 removes the cap)
    --window 30       trailing window in days
    --committee 100   committee size, used only for the active-24-hour total in E
    --presence 0      proposed presence gate, 0 = off (tested and rejected in results.md)

The runs behind `results.md`:

    python3 finality_sim.py
    python3 finality_sim.py --growth 1e9 --scenarios B --floors 1
    python3 finality_sim.py --presence 20 --scenarios C,D
    python3 finality_sim.py --seed 11 --scenarios A,B --floors 1,1000

Output is markdown tables on stdout. Days in B to E are counted from the event, so "+1" is
the first full day after the burst, the doubling or the churn.

Model limits are listed at the end of `results.md`: no latency, no DAG, no VRF sampling noise,
instant difficulty retarget, free keys.