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Felipe Fontoura Engineered with AI. Production systems that can't fail. Staff Engineer · Production Systems with AI · builder I build secure, reliable, scalable systems with AI agents. 25+ years…
Felipe Fontoura
Engineered with AI. Production systems that can't fail.
Staff Engineer · Production Systems with AI · builder
I build secure, reliable, scalable systems with AI agents. 25+ years shipping production software, from satellite kernel drivers at INPE to the global checkout serving 20M+ customers at TUI Group (€23B revenue), to a crypto fintech built solo in 70 days.
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What I built
A crypto fintech on Bitcoin's Liquid Network: a payment gateway, an OTC exchange, and on-chain settlement. Engineered solo in 70 days with AI agents. Private repo.
TypeScript Node.js Fastify PostgreSQL Kubernetes Terraform Redis BullMQ
- 13-app monorepo, 3 Fastify APIs, 3 isolated PostgreSQL databases
- PIX gateway, 4 PSPs behind a factory pattern (HMAC-SHA256, mTLS to BACEN)
- OTC exchange engine: rolling 24h VWAP, 5 sources, asymmetric spreads
- On-chain settler: confirmation polling, deviation refunds, crash recovery
- OAuth 2.1 / OIDC: 5 roles, 19 scopes, JWKS, M2M, TOTP 2FA
- Kubernetes (DOKS, HPA 2-10), Prometheus and Grafana, CI/CD
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How I build
Build the right thing, engineer it to hold, direct the agents that write it. The bar has always been production: satellites where a failed signal has no patch, a €23B checkout at 99.9% uptime, a fintech moving real money. The AI writes the code. The architecture, the specs, and the call on what "done" means are mine.
The method is plain: structured specs (requirements, design, tasks) are the source of truth, agents execute against them, humans review and ship. I have trained 400+ people in it.
- What Is Spec-Driven Development?, the complete guide
- Harness Engineering, stop upgrading the model and fix the harness
- How to write a spec an AI can build from, the EARS format and templates
Open source
- pi-sdd-kit: spec-driven development as skills for the Pi coding agent. Steering docs as durable memory,
.statusapproval gates, EARS, and a gated PRD to review pipeline. - pi-skill-model-handoff: let each Pi skill pick its own model and thinking level from the
SKILL.mdfrontmatter. - AI engineering dotfiles: slash commands, agent teams, review pipeline.
Writing
Notes on building production software with AI coding agents: harness engineering, spec-driven development, context, and architecture.
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Stack
| Backend | Infrastructure |
| --- | --- |
| Node.js / TypeScript | Kubernetes (DOKS) |
| Fastify / NestJS | Terraform |
| Drizzle ORM / Prisma | Docker |
| PostgreSQL | GitHub Actions CI/CD |
| BullMQ / Redis | Prometheus / Grafana |
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Links
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doc2md
Convert documents to Markdown format through a simple API service.
Python ★ 29 1y agoExplain → -
bento
Bento turns a fresh Ubuntu/Debian VPS into a hardened Docker Swarm server with Traefik, Portainer, TLS, and deployable apps through a guided terminal menu.
Shell ★ 19 18d agoExplain → -
ubinkaze
An comprehensive post-installation configuration tool for Ubuntu servers.
Shell ★ 19 1mo agoExplain → -
pi-sdd-kit
Spec-Driven Development skill pack for the Pi coding agent: steering docs, .status gates, EARS, and a PRD→SPEC→TASKS→EXEC→REVIEW pipeline.
★ 17 28d agoExplain → -
deepseek-local
My DeepSeek-R1 local machine test.
Python ★ 14 1y agoExplain → -
pyzerox-demo
A demonstration project showcasing the usage of PyZerox library for processing PDF documents using GPT-4 models.
Python ★ 8 1y agoExplain → -
paperclip-adapter-hermes-local-plus
Drop-in replacement for Paperclip's built-in hermes_local adapter — production-grade Hermes Agent integration with dynamic provider select, OpenAI-compatible custom providers, secret references, and 22% token-cost reduction.
TypeScript ★ 2 1h agoExplain → -
bitcoin-coders-bootcamp
Bitcoin Coders Bootcamp - Turma B
★ 2 3mo agoExplain → -
spec-driven-development-book
The definitive guide to Spec-Driven Development: build software with AI agents, from method to production code. Book in EN + pt-BR with a ready-to-use SDD kit for Claude Code.
★ 1 10d agoExplain → -
acme-store-sdd
Reference: running the Pi SDD Kit as a team on a GitHub Projects board (gates, .status automation, branch protection)
Shell ★ 1 11d agoExplain → -
pi-skill-model-handoff
Pi extension that switches model/thinking from skill frontmatter.
TypeScript ★ 1 28d agoExplain → -
pi-strategy
It helps technical builders avoid overbuilding by forcing clarity on market, user, problem, offer, MVP, proof, messaging, and acquisition.
★ 1 2mo agoExplain → -
hermes-paperclip-adapter ⑂
Paperclip adapter for Hermes Agent — run Hermes as a managed employee in a Paperclip company
★ 1 1mo agoExplain → -
paperclip-adapter-hermes-gateway
Paperclip external adapter for the Hermes Agent — talks to Hermes over HTTP, no CLI inside the Paperclip container.
TypeScript ★ 1 2h agoExplain → -
docker-swarm-stacks ▣
No description.
★ 1 10mo agoExplain → -
youtube-studio-mcp
MCP server for YouTube Data/Analytics/Reporting API — fork with transcript fix for youtube-transcript-api 1.x
Python ★ 0 10d agoExplain → -
base25-book-kit
Markdown → print-ready PDF (Typst) + EPUB 3 + KDP cover. Portable book engine with editorial typography, hand-drawn Mermaid diagrams, LaTeX math, and worksheets.
JavaScript ★ 0 11d agoExplain → -
BojuBot ⑂
More than a writing assistant — BojuBot turns your Obsidian vault into a personal AI platform
★ 0 16d agoExplain → -
felipefontoura
No description.
★ 0 25d agoExplain → -
awesome-openspec ⑂
Curated list of awesome OpenSpec resources and some genereric Spec-Driven-Development resources.
★ 0 25d agoExplain → -
awesome-spec-driven-development ⑂
A curated list of awesome resources for spec-driven development (SDD)
★ 0 28d agoExplain → -
mcp-pooler
Caching connection pooler in front of an aggregating MCP gateway (e.g. MetaMCP) — instant tool discovery + warm calls for ephemeral MCP clients.
Python ★ 0 1mo agoExplain → -
paperclip-skills-bridge
Stateless HTTP bridge that translates Paperclip skills into the .well-known/skills/ protocol the Hermes Agent already speaks.
JavaScript ★ 0 2d agoExplain → -
base25
Base25 — engineering foundation
TypeScript ★ 0 1mo agoExplain → -
excaliapp ⑂
An simple tauri app to look at and edit excalidraw files easily
TypeScript ★ 0 1mo agoExplain → -
aqua-wallet ⑂
AQUA is a free, open-source wallet for iOS and Android.
★ 0 4mo agoExplain → -
studio-deck
80s-style OBS Studio controller for Elgato Stream Deck and Pedal
Python ★ 0 7mo agoExplain → -
V0-system-prompt ⑂
No description.
★ 0 1y agoExplain → -
kamal ⑂
Deploy web apps anywhere.
Ruby ★ 0 1y agoExplain →
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