Design Token Vesting - System Design | WinJob

Problem Statement: Enterprise Token Vesting at Sablier Scale

Hedgey/Sablier-class programmable unlock where grantors lock ERC-20 inventory and beneficiaries withdraw only as time passes—no discretionary unlock button.

Mechanism (problem)

Grantor funds escrow; VestingCore enforces start, cliff, end timestamps
Indexer projects vested curve for dashboards; ChainWriter submits release when keepers economical
Beneficiary wallet or delegate calls withdraw with replay-safe nonce

Quantified anchors (sec-01)

Locked TVL target $18B locked with 2.4M active streams
Peak 420 schedule writes/s; claims 85k claims/day
Vested balance API p99 <180ms; vested amount drift vs chain <1 wei after finalize

Failure drills

problemA: grantor revokes 1s before cliff—beneficiary must not withdraw cliff lump.
problemB: L2 sequencer down—read API serves last finalized vested snapshot with banner.

Staff+ extensions

Reference Sablier Lockup Linear, Superfluid CFA, Hedgey NFT vesting when interviewer names real products
Mention ERC-20 allowance + permit2 for gasless grantor onboarding
Offer delegatecash / ERC-7715 only if delegation scope explicitly in requirements

javaOne Dark Pro

1 public final class VestingSection1 {
2   public static final String TOPIC = "problem";
3   public static long vestedWei(long t, long cliff, long slope) {
4     return t < cliff ? 0L : Math.min((t - cliff) * slope, Long.MAX_VALUE);
5   }
6 }

pythonOne Dark Pro

1 TOPIC_1 = "problem"
2 LOCKED_TVL_USD = 18_000_000_000
3 ACTIVE_STREAMS = 2_400_000

typescriptOne Dark Pro

1 export const SECTION_1 = { topic: 'problem', phase: 'understanding', vestedSloMs: 180 };

Why interviewers care

Token Vesting interviews reward crisp scope, explicit trade-offs, and failure stories—not generic microservice diagrams.

Interview checkpoint

Name one failure story for Problem Statement: Enterprise Token Vesting at Sablier Scale that proves you understand real outages, not happy-path diagrams.

Key Highlights

•Grantor ↔ Beneficiary boundary (problem)
•VestingCore enforces cliff + slope (problem)
•Phase understanding: problem focus

1	public final class VestingSection1 {
2	public static final String TOPIC = "problem";
3	public static long vestedWei(long t, long cliff, long slope) {
4	return t < cliff ? 0L : Math.min((t - cliff) * slope, Long.MAX_VALUE);
5	}
6	}

1	TOPIC_1 = "problem"
2	LOCKED_TVL_USD = 18_000_000_000
3	ACTIVE_STREAMS = 2_400_000