Michał Mirończuk

Experience

• Jan 2025 – Jul 2026

  LI.FI

  Smart Contract Engineer | Partner Integrations & Security · Remote

  • LI.FI is a bridge and DEX aggregator on 70+ chains. Its contracts move roughly $5B a month and have moved $80B+ in total.
  • Ran four partner bridge integrations (NEAR Intents, Unit, Polymer, Glacis) from brief to production. Three of them carry ~30% of LI.FI’s bridge volume.
  • Owned the emergency pause. Built our side of the Hexagate integration, a CI check of pause-readiness on every chain, and the runbooks for testing it.

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  • Scoped each integration with the partner’s engineers and agreed what sits on whose side.
  • Prototyped the happy path of each integration in TypeScript on the partner’s SDK.
  • Polymer, a USDC route over Circle CCTP, became the second-largest route on LI.FI.
  • Reproduced failed cross-chain transfers and used the failing transaction to show which side broke.
  • One bug sat in a partner’s contract. Others came from SDKs that did not match their docs.
  • Treated every partner as untrusted, so the safeguards sit in LI.FI’s contract.
  • Moved the allowlist of DEX and router calls from per-contract to per-function checks.
  • Shipped that change on ~30 live contracts through an external audit, with no storage migration possible.
  • Was responsible for EIP-712 verification of bridge transfers signed by our backend. The contract rejects a signature that has expired or was issued for another chain or contract.
  • Handled external audits (Spearbit, Burrasec) from scope to fixes.
  • Triaged reports from the Cantina bug bounty.
  • Shipped upgrades through Safe multisig and timelock.
  • Owned the Olympix and Hexagate (now Chainalysis) vendor relationships.
  • Evaluated Olympix’s three tools against the same work done by hand. We bought only the static analysis, the one tool that met the requirements.
  • Replaced manual releases with one pipeline for 70+ networks, Tron included. It runs the deploy scripts, CI gates and readiness checks (TypeScript, viem, GitHub Actions).
  • Onboarded new networks end to end, EVM and non-EVM.
  • Built the team’s agent tooling on Claude Code (skills, hooks, subagents, MCP) for deploys, PR review and triage. Four engineers used it daily.
  • Co-built a background agent in Slack. When someone shared a transaction link, it analyzed the transaction and replied with a summary. The support team used it.
  • Designed a vault wrapper for LI.FI Earn with integrator fees, KYB allowlists and sanctions checks.
  • Wrote its spec after settling the open options with the business in writing.
  • Covered on-call for the contracts, including issues reported by integrators building on LI.FI.
  • Wrote the integration docs, the runbooks for testing the emergency pause and the security reports for external clients.
• Oct 2023 – Dec 2024

  Instadapp

  Smart Contract Engineer · Remote

  • Built the ERC-4626 vault system for Fluid from scratch. Fluid had ~$1B TVL across lending, vaults and DEX.
  • Wrote the liquidation logic and oracle integrations (Chainlink, RedStone, Uniswap TWAP).

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  • Tested the vaults, liquidations and oracles with Foundry invariant and fuzz suites.
  • Contributed to the Flash Loan Aggregator, which routes each flash loan to the cheapest of Aave, MakerDAO, Balancer, Uniswap and Compound.
  • Fluid’s contracts are public in Instadapp/fluid-contracts-public, as a snapshot without commit history.
• Oct 2025 – Present

  PytajOLek

  Founder & Engineer · Poznań, Poland

  • Built and run a drug-information product for the Polish market on my own. It has 11k indexed pages and ~90 daily users, all organic.
  • Kept the LLM out of drug-interaction warnings with a deterministic engine on SmPC and DDInter2 data. Each warning is citable and reproducible.
  • Releases ship only after LLM-as-judge tests on clinical answers and a HealthBench-based benchmark pass on two model providers.

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  • Stack: Next.js and TypeScript, FastAPI and Python, MongoDB, Redis and Docker. CI runs 1,000+ tests.
  • Built the Claude agent and its MCP tools, with Langfuse tracing.
  • Built RAG over SmPC documents. The section holding the answer reaches the model in 94.6% of 10,440 questions, up from 47.5%, with half the context.
  • Tested vector retrieval and dropped it because the gain was too small.
  • Built a daily ETL that syncs 23k+ records from the EMA and the Polish medicines registry, plus NFZ reimbursement lists.
  • LLM text is regenerated only when its source changes, so API cost stays flat.
  • Users can photograph several drugs at once. Claude reads the photo. The same deterministic engine then checks the interactions. Photos are never stored.
  • Measured that 48% of real queries contain health data, a special category under GDPR. Built masking of PESEL numbers in logs and traces.
  • Ran a pilot aimed at doctors and did customer discovery at Warsaw Medical Expo 2026.
  • Most professional users turned out to be vets. Pharmacists got their own mode.
• Sep 2022 – Oct 2023

  VERITIC

  Blockchain Developer · Zurich (remote)

  • Built a no-code contract management tool on top of Safe multisigs and custody, on EVM chains and the non-EVM Casper Network.
  • React front end and a serverless Node back end on AWS Lambda and S3.

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  • Added NFT marketplace features: royalties and lazy minting.
  • Queried smart-contract events in BigQuery to see if upgradeable contracts were becoming more common.
  • The trend went into the decision on whether the tool should let admins upgrade contracts.
  • Rolled the tool out with client teams and pitched it to investors at Consensus 2023.
  • VERITIC was a Consensus 2023 finalist and took 1st place at venture.ch Switzerland 2022.
• Jun 2021 – Sep 2022

  ChainGain

  Blockchain Developer · New Zealand (remote)

  • P2P lending platform. Wrote production smart contracts in Rust (CosmWasm on Terra) and Solidity.
  • Built the NestJS back end on AWS EC2 and the React and ethers.js front end.

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  • Built the Solidity contracts with Hardhat.
• Dec 2020 – Jun 2021

  Mysa

  Blockchain Developer · Poznań, Poland

  • Tokenized real estate (RWA) on Solidity and the non-EVM Hedera network.
  • Built AWS-native dApps. Mysa won the AIBC Malta Summit 2021 out of 500+ projects.
• May 2020 – Feb 2021

  Art_Value

  Blockchain Developer / Team Lead · Stockholm, Sweden

  • Led a 3-4 person engineering team: estimation, sprint planning, code review and technical decisions.
  • Shipped ERC-721 marketplace contracts with deposit and escrow flows.

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  • Built NestJS and TypeScript microservices and a React and web3.js front end.
• 2018 – 2020

  THINQ Development · Alliance Technology Polska

  .NET Developer (C#) · Poznań, Poland