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.
GovernanceNon-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.
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.