Design Airdrop Distribution

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understanding•8 min read

Problem Statement: Token Airdrop at L2 Scale

Problem Statement: Token Airdrop at L2 Scale — airdrop distribution interview depth

Airdrop angle (sec-01)

Uniswap/Optimism/Blur-class token airdrop distributing allocations to millions of wallets with sybil resistance, Merkle claims, and gas-sponsored UX. Section 1 covers problem in the understanding phase.

Problem Statement: Token Airdrop at L2 Scale

Mechanism (problem)

  • off-chain eligibility snapshot
  • on-chain Merkle claim
  • sybil scoring pipeline
  • gas-sponsored meta-tx relay

Quantified anchors (sec-01)

  • 5.2M eligible wallets; 2.1M expected claims in week one
  • Peak 900 claim RPS; proof CDN 94% hit ratio target
  • $500M notional at $0.12/token; 32-byte root anchored on L2
  • Sybil duplicate budget <0.3% of allocations; claim API 99.95% monthly availability

Failure drills

  • Drill 1A: wrong Merkle root published—pause OPEN, emit campaign.paused, rotate proof version v2.
  • Drill 1B: relayer gas tank empty—switch to user-paid path with estimator, cap queue depth 50k.
  • Drill 1C: indexer lag > 30s—show "confirming" state, block duplicate claim-intent without receipt.

Staff+ extensions

  • Reference Uniswap LP weighting, Optimism governance snapshot, Blur bid-wall activity as eligibility examples
  • Offer proof-of-personhood quorum when interviewer challenges sybil
  • Separate off-chain eligibility (fast) from on-chain claim truth (slow finality)

Design narrative

Depth 1.1 (problem): off-chain eligibility snapshot must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-0. Depth 1.2 (problem): on-chain Merkle claim must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-1. Depth 1.3 (problem): sybil scoring pipeline must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-2. Depth 1.4 (problem): gas-sponsored meta-tx relay must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-3. Depth 1.5 (problem): off-chain eligibility snapshot must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-4. Depth 1.6 (problem): on-chain Merkle claim must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-5. Depth 1.7 (problem): sybil scoring pipeline must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-6. Depth 1.8 (problem): gas-sponsored meta-tx relay must stay consistent with idempotent claim ledger, root publication ceremony, and sybil review before OPEN—problem-1-L2Scale-line-7.

Interview checkpoint (sec-01-understanding)

  • Lead with off-chain eligibility snapshot and cite claim state machine: ELIGIBLE → PROOF_ISSUED → SUBMITTED → CONFIRMED.
  • Explain CAP: CP claim row in Postgres, AP chain receipt via indexer repair.
  • Tie Problem Statement: Token Airdrop at L2 Scale to measurable fairness and claim SLO—not generic "blockchain scale" talk.
javaOne Dark Pro
1public final class AirdropSec1 {
2  public static final String TOPIC = "problem";
3  public static boolean canClaim(String status) {
4    return "PROOF_ISSUED".equals(status) || "ELIGIBLE".equals(status);
5  }
6}
pythonOne Dark Pro
1TOPIC_1 = "problem"
2PEAK_CLAIM_RPS = 900
3ELIGIBLE_WALLETS = 5_200_000
typescriptOne Dark Pro
1export const SECTION_1 = { topic: 'problem', phase: 'understanding', peakClaimRps: 900 };

Why interviewers care

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

Interview checkpoint

Name one failure story for Problem Statement: Token Airdrop at L2 Scale that proves you understand real outages, not happy-path diagrams.

Key Highlights

  • •Uniswap/Optimism/Blur-class fairness
  • •Merkle claim + sybil gate
  • •Phase understanding: problem focus
Mention this
Tie Problem Statement: Token Airdrop at L2 Scale to sybil budget, Merkle root ceremony, and idempotent claim API.
Staff+ signal
Publish root before OPEN; never let UI counters override on-chain claim guards.

Section Rescue Kit

Buzzwords to use:

Merkle DistributorSybil graph

Safe statements:

  • "For Problem Statement: Token Airdrop at L2 Scale, I'll pause OPEN if root bytes disagree with signed manifest."
  • "I'll walk snapshot → sybil → root → claim when stuck."
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