open to work Copenhagen

Adis Begic

Systems where a wrong answer is expensive.

About

Securing blockchain protocols and shipping payment and trading systems taught me that the happy path is the easy part. The hard part is the retry that charges twice, the message that arrives out of order, and the state that's gone after a restart.

AI agents now run into the same problems. They call real APIs, retry when a step fails, and carry state through tasks that run for hours. It's the area I find most interesting right now, and nobody has clean answers yet, me included.

Experience

  1. Principal / Founding Engineer · Stealth Startup (NDA)

    2025 — 2026

    Architected an event-sourced trading platform: 15 microservices on EventStoreDB and NATS JetStream, safe settlement retries through idempotent commands and outboxes, and multi-tenant encryption. Wrote the 41-document spec it's built from and backed it with 30,000+ tests.

    NestJS · EventStoreDB · NATS JetStream · CQRS · Distributed Systems

  2. Co-Founder & Lead Smart Contract Auditor · Chain Integrity

    2021 — 2025

    Co-founded a blockchain security firm and led 50+ audits and builds for production DeFi protocols. Built our audit methodology and tooling for invariants, access control and economic exploits, and ran client delivery from scoping to presenting findings to leadership.

    Solidity · EVM · Foundry · Invariants · Fuzzing · Slither · Threat Modeling

  3. Cybersecurity Platform Engineer & Researcher · JS Security

    2020 — 2021

    Worked on the security layer of a decentralized enterprise storage platform on Hyperledger Fabric: cryptographic access control and a software HSM integration for key management.

    Hyperledger Fabric · Go · HSM · ABE/PRE · gRPC

  4. Full-Stack Blockchain Engineer · Freelance

    2016 — 2020

    Designed and delivered gas-optimized smart contracts and full-stack DApps for clients across DeFi staking, linear vesting and NFT lending, working directly with each client from spec to launch.

    Solidity · EVM · Hardhat · web3.js · TypeScript · React

Skills

Languages
TypeScript  Python  Rust  Solidity
Distributed Systems
Event sourcing and CQRS  Exactly-once processing  Workflow orchestration  NATS JetStream
AI Agents
MCP servers  Agent evaluation and replay  Durable agent state  LLM gateways & observability
Security
Least privilege  Key management  Tenant isolation  Agent security  Smart contracts  Container hardening
Platform
PostgreSQL  GraphQL Federation  OpenTelemetry  Prometheus & Grafana  AWS
Blockchain
Bitcoin Core  EVM  SVM  Foundry  DeFi  Market making  Mechanism design

Upstream

  1. pydantic/logfireReturn the LLM response when recording it fails
  2. pydantic/logfireRead stable database semconv attributes in DB span messages
  3. pydantic/logfireDon't let Litestar routing errors escape span naming
  4. promptfoo/promptfooHonor the cache setting from a config passed with -c
  5. LuganoPlanB/bitcoin-rootsReport the configured RBF policy in getmempoolinfo
  6. LuganoPlanB/bitcoin-rootsAccount for priority-selected ancestors when building blocks
  7. celery/celeryUpsert CosmosDB results so later task states are stored
  8. temporalio/sdk-pythonFix Google ADK agents with output_schema
  9. deepset-ai/haystack-core-integrationsKeep every bound when merging same-field range filters
  10. anthropics/buffaReturn a borrowed empty message for unset message fields

Open source

Writing

  1. Security Is Not a Tool the Agent CallsSecurity / Agents 6 min read
  2. Tokens Are the Cheapest PartAI Engineering / Efficiency 6 min read
  3. Usage Is Not Quality, and Neither Is ValueAI Quality / Leadership 11 min read
  4. Agent Patterns Are Sorted by the Wrong AxisAgents / Architecture 10 min read
  5. Agents Need Idempotency KeysAgents / Reliability 9 min read
  6. Retrieval Strips the PermissionsSecurity / Retrieval 11 min read
  7. Learning Agents Deploy ThemselvesAgents / Evals 10 min read
  8. Prompt Caches Leak Across TenantsSecurity / Inference 11 min read

Teaching

  • Copenhagen Institute of Interaction Design (CIID)
    Guest Lecturer · Blockchain Architecture
  • Polytechnic Institute of Paris (IP Paris)
    Guest Lecturer · Smart Contract Design

Contact

Open to security, AI and platform engineering roles.
Email is the fastest way to reach me.