Software engineer, Bucharest. 10 years building backends, microservices, and the occasional cryptographic protocol — mostly in places where the cost of being wrong is high: identity, payments, compliance.

Portfolio and write-ups → ionelmerca.com

• EUDI Wallet — a working EU Digital Identity wallet, assembled from the two libraries below plus a 72-line adaptor. Full issue → hold → present journey against the live EU reference issuer and verifier.
• SD-JWT VC + OpenID4VC — pure-Dart holder library for selectively-disclosed verifiable credentials. Key- and HTTP-agnostic, 100% covered. → sdjwt_oid4vc
• Attested Secure Keys — hardware-backed, non-exportable EC P-256 keys for Flutter, with server-verifiable attestation. Android StrongBox/TEE and iOS Secure Enclave. → attested_secure_keys
• Agent Commerce on AP2 — cryptographically signed mandates for agent-mediated payments. Ed25519 / JCS / did:web, three-party trust chain.
• cryptobot — systematic crypto trading on Binance: 16 strategies, Redis-backed backtesting, and an honest read on the results.
• The Graph of Romanian Businessmen — 6.8 GB of Official Gazette PDFs turned into a searchable graph of ~370,000 people.

Based in Bucharest, working across Europe.