Largeton Group

Blockchain QA Engineer

Largeton Group

22 days ago

## Summary **Blockchain QA Engineer** ## Job Summary - Ensure correctness, security, and reliability of a verifiable financial data platform anchored to blockchain. - Validate data-heavy pipelines and ensure ISO 20022 semantic consistency. - Test blockchain attestation logic, including cryptographic proofs and smart contracts. - Validate end-to-end chain of custody for financial records: canonicalization, cryptographic integrity, blockchain attestations, selective disclosure, and reconciliation. - Design, implement, and maintain automated test suites for backend APIs (Golang), smart contracts (Solidity/EVM), and data pipelines (ETL/normalization). - Conduct rigorous manual testing for complex financial transaction edge cases. - Perform functional and security testing of smart contracts; validate on-chain state transitions and event emissions. - Test scenarios involving chain reorganizations, gas spikes, network latency, and failed attestations using tools like Hardhat, Foundry, or Truffle. - Validate ISO 20022 semantic mapping and perform differential testing to ensure data fidelity. - Test Merkle tree construction and proof inclusion logic. - Conduct load and fuzz testing on data ingestion, proof-generation services, smart contracts, and API endpoints. - Collaborate with Cybersecurity to validate identity and provenance layers. - Integrate blockchain testing into CI/CD pipelines (ArgoCD/GitHub Actions). - Develop custom scripts (Python, Go, JS) for test data and event stream simulation. - Track and document bugs, providing clear reproduction steps. ## Requirements - 4+ years of QA/SDET experience - 2+ years in blockchain/Web3 QA - Proficiency in at least one programming language (Golang, Python, JS/TS) - Experience with blockchain testing frameworks (Foundry, Hardhat) - Experience with API testing tools and cryptographic primitives - Bachelor's degree in Computer Science, Engineering, or related field; advanced degrees or MBAs are a plus ## Nice-to-Have - Experience in US financial services/fintech - ISO 20022 knowledge - ZKP systems experience - GitOps/ArgoCD experience - Identity frameworks experience - Performance testing tools (k6, JMeter) --- When applying, mention the word **CANDYSHOP** to show you read the job post completely.