TYPE 0x0801 · GOVERNANCE FAMILY

EPOCH_GATE

Periodic spending windows — allows a UTXO to be spent only during specific portions of each epoch. Uses block height modular arithmetic to create recurring open/closed gates. No Tapscript equivalent exists.

Governance Non-Invertible

Ladder Diagram

Fields

Field	Data Type	Size	Side	Description
epoch_size	NUMERIC	1-4 B	Conditions	Number of blocks per epoch (must be > 0)
window_size	NUMERIC	1-4 B	Conditions	Number of blocks at start of epoch where spending is allowed (must be ≤ epoch_size)

No witness fields required — evaluation uses only the current block height from the evaluation context.

Wire Format Breakdown

0x0801 0 2 NUMERIC · 3B NUMERIC · 3B Conditions = 14 bytes

0x0801 0 0 Witness = 4 bytes (empty block)

Total 18 bytes

Evaluation Logic

1.Collect conditions NUMERIC fields. Fewer than 2 → ERROR. ReadNumeric the first as epoch_size and the second as window_size; either undecodable → ERROR

2.Validate: epoch_size ≤ 0, window_size ≤ 0, or window_size > epoch_size → ERROR

3.Defensive guard: ctx.block_height < 0 → ERROR (catches the test-harness path where block_height is -1; C++ % with a negative LHS would yield a negative position and confuse the comparison).

4.Compute position = ctx.block_height % epoch_size. If position < window_size → SATISFIED; else → UNSATISFIED

Return Values

Condition	Result
Fewer than 2 NUMERIC fields, or either undecodable	ERROR
`epoch_size ≤ 0`, `window_size ≤ 0`, or `window_size > epoch_size`	ERROR
`ctx.block_height < 0` (test-harness defensive guard)	ERROR
`block_height % epoch_size ≥ window_size`	UNSATISFIED
`block_height % epoch_size < window_size`	SATISFIED

JSON Wire Format

Conditions (epoch=2016, window=144 blocks)

{
  "type": "EPOCH_GATE",
  "inverted": false,
  "fields": [
    { "type": "NUMERIC", "value": 2016 },
    { "type": "NUMERIC", "value": 144 }
  ]
}

This creates a gate that opens for the first 144 blocks (~1 day) of every 2016-block epoch (~2 weeks). Spending is only valid during the open window.

Worked Example

epoch_size = 2016, window_size = 144

Block 100: 100 % 2016 = 100. 100 < 144 → GATE OPEN

Block 143: 143 % 2016 = 143. 143 < 144 → GATE OPEN (boundary)

Block 144: 144 % 2016 = 144. 144 ≥ 144 → GATE CLOSED

Block 200: 200 % 2016 = 200. 200 ≥ 144 → GATE CLOSED

Block 2016: 2016 % 2016 = 0. 0 < 144 → GATE OPEN (new epoch)

Use Cases

Treasury Disbursement Windows

DAO treasury funds can only be spent during the first day of each difficulty adjustment period. This creates predictable governance cycles and prevents impulsive spending.

Rate-Limited Withdrawals

Exchange cold wallets can only process withdrawals during specific block windows, giving security teams time to review and intervene between windows.

Inverted: Lockout Periods

With the inverted flag, spending is blocked during the window — creating mandatory hold periods. Useful for vesting schedules where tokens can only be moved outside of lockout windows.

← ANCHOR_FEE WEIGHT_LIMIT →