Senior Blockchain Engineer for On-Chain Indexer Setup

Silverline Labs

Contract · Remote · Flexible hours

About the role

Silverline Labs is building a next‑gen mobile marketplace that syncs tightly with its backend services for a seamless app‑store launch. As a Blockchain Engineer you will design and implement smart‑contract layers that power in‑app token transactions and ensure data consistency between the mobile front‑end and the server APIs.

Key responsibilities

• Develop Solidity smart contracts for token minting, escrow, and revenue sharing aligned with the mobile payment flow.
• Integrate contracts with the existing Node.js backend using Web3.js and ethers.js, creating REST endpoints for mobile clients.
• Write automated tests in Hardhat and Truffle, achieving 90% coverage before the beta release.
• Collaborate with iOS/Android teams to define data schemas that map on‑chain events to app UI updates.
• Set up CI pipelines in GitHub Actions for contract compilation, linting, and deployment to a private testnet.
• Document contract APIs and versioning strategy for the upcoming app store submission.

Must-have skills

• Strong experience with Solidity and smart‑contract development.
• Proficiency in JavaScript/TypeScript for Web3 integration.
• Hands‑on knowledge of Ethereum tooling (Hardhat, Truffle, ethers.js).
• Understanding of mobile‑backend synchronization patterns.
• Experience with security best practices for on‑chain code.

Nice to have

• Familiarity with Polygon or other L2 scaling solutions.
• Background in Python scripting for blockchain analytics.