Michal Stefanow

Built and maintained multi-chain blockchain backend infrastructure across Bitcoin, Ethereum, and Solana, including RPC integrations, transaction processing, wallet services, smart contracts, indexing, and real-time data pipelines. Designed scalable backend services and APIs using Node.js/TypeScript and Rust, with PostgreSQL/Redis, event-driven architectures, Kafka/NATS, Docker, Kubernetes, Terraform, and AWS/GCP, and also contributed with Go. Owned Bitcoin transaction-processing and indexing services with Bitcoin Core RPC, BitcoinJS, and PSBT, including Taproot/BIP-340 workflows and secure wallet APIs. Developed Ethereum and Solana backend integrations for DEX/DeFi and multi-chain asset flows (Ethers.js/viem and Solana Web3.js), plus cross-chain infrastructure between Ethereum and Solana for transaction lifecycle and validation. Implemented production monitoring, security practices, and operational processes using Slither/MythX, Prometheus, and Grafana, and supported audits/vulnerabil

Built backend services for institutional staking products, covering staking lifecycle, transaction preparation, validator/reward data, and wallet integrations across multiple Proof-of-Stake networks. Designed common service interfaces to standardize chain-specific staking workflows so new protocols could be onboarded without rebuilding transaction/reporting stacks per network. Developed Go services for transaction crafting, staking and reward aggregation, and PostgreSQL-backed internal APIs with asynchronous processing for chain events and operational updates. Integrated blockchain data across Ethereum, Solana, and other PoS networks while preserving protocol concepts such as validator/delegator identifiers, epochs, activation state, exits, and rewards. Implemented idempotent processing, retries, reconciliation jobs, and status tracking to safely recover from delayed RPC responses, duplicate events, and temporary chain/provider failures, and supported operational monitoring and incide

Owned end-to-end delivery of enterprise provenance features, spanning Go backend services, React-based web interfaces, and private-blockchain integrations—translating product requirements into production architecture across layers. Designed asset lifecycle workflows around digital twins, provenance events, certification data, and ownership transfer to keep physical objects and their blockchain records consistent across supplier, retailer, and consumer journeys. Built and evolved REST APIs and partner integrations for asset ingestion, search, provenance retrieval, and custody transfer with validation, idempotency, and clear error handling for inconsistent upstream data. Delivered customer-facing dashboards and embeddable provenance experiences that surface immutable origin, compliance, sustainability, and ownership information without exposing users to blockchain complexity. Contributed to DevOps and reliability by containerizing services, managing CI/CD, deployments, monitoring, and