Marco Santana

Own the backend, Protobuf contracts and offline-first Flutter field app of a trade-marketing platform: 125 merged MRs across five repositories in ten weeks, BFF tests 84 → 725, app tests 145 → 736, 21 tester builds in 24 days. Cut a 1.29M-row paged query from ~35 s to ~2 s by pushing LIMIT/OFFSET down to Trino in the Python query engine; redesigned a 46M-row out-of-memory aggregation to ~12 s per page. Benchmarked Trino against StarRocks on replayed production dashboard loads, led a compute-amplification audit across four services, built an AWS FinOps pipeline that surfaced savings worth 30–60% of monthly spend, and published 21 architecture pages through a Wiki.js publisher I wrote. Earlier in the year: 165 commits hardening the Golyzer React 18 / Vite / Module Federation modernization, a TipTap rich-text editor and a conditional-formatting engine. Run a governed multi-session Claude Code workflow (64 parallel worktrees, guard hooks, quality-gate skills) and wrote the team hook that keeps agents from approving or merging MRs.

ISP operations platform (React 19, TanStack, FastAPI, SQLModel, PostgreSQL, Redis). Sole author of the CRM module: a 28-table schema, 16 Alembic migrations, 105 FastAPI endpoints behind 103 RBAC capabilities, and a kanban, lead workspace and proposal editor with triggers and cadences — 115 commits and 42.8k lines, with 248 pytest functions, the repository's first Playwright suite (105 cases) and a 233-case client validation page. Introduced pull-request delivery to a team that merged straight to main; 23 merged PRs and 409 commits, the most of any contributor during the engagement. Built a guard-railed agent harness for client work (PreToolUse hook, critical-values scanner, pre-push LLM review, parallel agents in isolated working copies); a multi-agent pass took the TypeScript build from 100 errors to 0. 446 logged hours in five months alongside full-time employment, with 22 engineering reports in English.

Products, open source and agent tooling, built with coding agents under written process (issue before commit, zero-warning gates, human-only issue closure). Chordo Pro is published on the Apple App Store (iOS, macOS) and the Microsoft Store, with the ICLF specification, parser and music-theory library open-sourced alongside it; Alpha Tester and GeoDome are live on the web. Tooling: claude-multi routes Claude Code across three subscriptions by directory; spent is a time-tracking CLI with 108 tests that publishes client reports; an 8-agent audit of my own practice and a 5-agent review of 8,662 prompts drive the harness roadmap.

Focused period after four years at H2O.ai. Designed the ICLF chord notation specification and built the first prototypes of the Chordo ecosystem — parser library, music theory engine, and cross-platform app.

Built and maintained the user interface of H2O.ai's machine-learning platform in React and TypeScript, in a US distributed team with English as the working language. Developed shared component libraries, collaborated closely with design and backend teams, and contributed to internal developer tooling.

Designed and delivered features for a North American e-procurement SaaS, working directly with the client in English, progressing from senior engineer to technical team lead.