gno.land/r/moul/x/daily/cliffvestingdemo/v0⧉

# Cliff Vesting

A pure vesting calculator, demoing the [`p/moul/x/daily/cliffvesting`](/p/moul/x/daily/cliffvesting/v0) library.

## A 12-month grant with a 3-month cliff

`1200` tokens, `Start = 0`, `Cliff = 3`, `End = 12`.

| month | vested | unvested | % |
|---|---|---|---|
| 0 | 0 | 1200 | 0% |
| 1 | 0 | 1200 | 0% |
| 2 | 0 | 1200 | 0% ← nothing yet |
| 3 | 300 | 900 | 25% ← **cliff** |
| 4 | 400 | 800 | 33% |
| 5 | 500 | 700 | 41% |
| 6 | 600 | 600 | 50% |
| 7 | 700 | 500 | 58% |
| 8 | 800 | 400 | 66% |
| 9 | 900 | 300 | 75% |
| 10 | 1000 | 200 | 83% |
| 11 | 1100 | 100 | 91% |
| 12 | 1200 | 0 | 100% ← fully vested |

The cliff is a **step, not a ramp**: at month 3 a quarter of the term has elapsed, so `300` tokens unlock at once. After that it accrues linearly.

## Claiming

The library tracks no balances — the caller supplies what has already been claimed:

| at month | already claimed | claimable |
|---|---|---|
| 6 | 0 | 600 |
| 6 | 300 | 300 |
| 6 | 600 | 0 |
| 12 | 600 | 600 |

## Integer rounding

All arithmetic is integer — no float ever reaches consensus state. Rounding is **down**, so nobody is ever paid more than they earned, and the final instalment collects the remainder.

`1000` over `3` periods:

| t | vested |
|---|---|
| 0 | 0 |
| 1 | 333 |
| 2 | 666 |
| 3 | 1000 |

`333 + 333 + 334` — the end is exactly `1000`, never `999`.

## The bug this avoids

When the total is smaller than the duration, computing a per-tick rate first truncates it to zero and **nothing ever vests**. Multiplying before dividing keeps it honest — `7` tokens over `1000` ticks:

| t | vested |
|---|---|
| 100 | 0 |
| 150 | 1 |
| 500 | 3 |
| 1000 | 7 |