Time Locks & Access Control
Beginner
30 minutesBlock-Height Time Lock (Timelocked Payments)
Lock funds until a specific block height for scheduled payments
Problem
You need to lock funds until a future date for vesting, escrow, or scheduled payments.
Solution
ErgoScript can check the current block HEIGHT against a target. Funds remain locked until the blockchain reaches the specified height (~2 min/block on Ergo).
How It Works
- 1Calculate target block height: current + (days * 720) for approximate timing
- 2Ergo averages ~2 minutes per block (720 blocks/day)
- 3Contract checks HEIGHT >= targetHeight before allowing spend
- 4Before target: funds are locked, no spending possible
- 5After target: only the designated beneficiary can claim
Code Examples
{
// Lock until block height 1,500,000
val unlockHeight = 1500000
val beneficiary = PK("9f...") // Beneficiary public key
// Can only spend after unlock height
HEIGHT >= unlockHeight && proveDlog(beneficiary)
}Simplest time lock. Funds are locked until the specified block height, then only the beneficiary can claim.
Use Cases
- →Team token vesting schedules
- →Scheduled salary payments
- →Escrow with timeout refunds
- →Inheritance and succession planning
- →Delayed governance execution
- →Bond maturity contracts
Security Considerations
- !Block times can vary slightly - don't rely on exact timing
- !Consider adding emergency unlock with multi-sig
- !Test unlock conditions thoroughly on testnet
- !Keep fee reserves for future unlock transactions
Resources
Fee Considerations
Standard transaction fees. Reserve ~0.01 ERG for future unlock transaction.