Full-stack Engineer and Systems Architect

🇧🇷 🇦🇷 🇨🇴 🇲🇽 🇵🇾 🇨🇱 🇨🇷 🇵🇪 🇺🇾 Exclusive to candidates based in Brazil, Argentina, Colombia, Mexico, Paraguay, Chile, Costa Rica, Peru, and Uruguay

Requirements Must-haves

• 8+ years of software development experience

• Proficiency with TypeScript

• Proficiency with Python

• Experience directing AI coding agents with rigorous review and verification practices

• Experience building component-driven front-ends and data-heavy internal consoles

• Experience with Postgres, including migrations, indexing, and query performance diagnosis

• Experience with containers and production deployments

• Experience with monorepos and multi-repos (e.g., workspaces, shared packages, versioned internal contracts)

• Experience building CI/CD pipelines (e.g., merge gates, reproducible builds, release and rollback, environment parity)

• Experience owning system architecture decisions in production

• Experience implementing protocols against specifications and building the conformance tests

• Experience with messaging APIs (e.g., carrier, WhatsApp, chat)

• Experience in instrumenting systems and reading traces for observability

• Ability to become productive with unfamiliar frameworks within a day

• Ability to hand-code and deeply review AI-generated code

• Deep understanding of typed schemas as a single source of truth, generated clients, and centralized validation

• Deep understanding of UX quality for pixel-perfect feature execution

• Interest in cutting-edge technologies and proposing new ideas for internal tools

• Strong communication skills in both spoken and written English

What makes you stand out

• Senior-level experience backed by strong, independent judgment

• Ability to troubleshoot hands-on without relying on AI coding tools

Nice-to-haves

• Startup experience

• Experience with business messaging platforms in production (e.g., Apple Messages for Business, RCS Business Messaging, WhatsApp Cloud API)

• Experience with Rust, Swift

• Experience with iOS or Android device automation, or computer vision applied to testing

• Experience designing certification, audit, or compliance systems

• Bachelor’s Degree in Computer Engineering, Computer Science, or equivalent

What you will work on

• This is an architecture role that writes code, not a coding role that occasionally diagrams.

• The hard problems here are not framework problems. There are questions like:

• What is the right abstraction for behavior that must stay identical across brands with wildly different experiences?

• Where does a system have to be deterministic and reproducible, and where can human judgment live?

• What belongs in a shared contract versus a local implementation?

• How do you make a system's invariants checkable rather than aspirational?

• We need someone who thinks in systems and concepts first, and who can then build the thing. Specifically:

System architecture and concept design

• Define service boundaries, data models, and contracts between components

• Design seams that let the same code run locally and hosted without a rewrite

• Turn fuzzy capabilities into clear models of core entities and rules

• Apply MIT concept design methodologies to agentic system design

• Design abstractions that keep behavior consistent across brands with very different experiences

• Decide where systems must be deterministic and where human judgment can apply

• Make architecture decisions alongside founders with product and engineering backgrounds

Verification and documentation

• Plan up front how each system will prove its correctness, rather than retrofitting tests

• Make system invariants checkable through code and tests

• Write specifications, decision records, and product invariants in RFC 2119 language

Agent-driven development

• Direct AI agents to build features and review their output in depth before merging

• Write specs that agents can execute and reviewers can check

• Maintain agent instructions and skills as first-class artifacts

• Run independent adversarial reviews before opening pull requests

• Catch plausible but wrong results (e.g. silent safety gates, empty version pins, hollow dependency directories)