I’m expanding an existing application onto the blockchain and need a mid-level engineer who can own the integration layer from end to end. Your main focus will be wiring our current back-end and front-end services into one or more public or permissioned chains, exposing clean APIs, and ensuring data flows remain secure and reliable. Key outcomes I’m looking for: • Design and implement the bridge between our app and the target chain(s), handling wallets, transactions, events, and any required off-chain storage. • Write clear, well-tested code (TypeScript, Go, or Python preferred, though I’m open if you can justify another stack). • Set up and document dev, staging, and production environments so the team can deploy with one-click CI/CD. • Proactively spot security gaps—replay protection, signature validation, rate-limiting—and patch them before they become issues. • Produce concise technical docs so future teammates can extend the integration without reverse-engineering your work. Although the initial scope is integration, knowledge of smart contracts and security audits will be appreciated because they often surface during implementation. You should be comfortable collaborating over GitHub, chatting on Slack, and demoing progress in short sprints. If you’ve previously connected SaaS or fintech products to Ethereum, Hyperledger, Binance Smart Chain, or similar networks—even better. Share links to repos, live demos, or architecture diagrams showcasing integration work you’ve led or contributed to. I’m ready to start as soon as I meet the right person. Let’s discuss milestones and dive in.