Sr Full Stack Engineer (React + JavaScript + TypeScript

About The Opportunity
We are looking for a Senior Full-Stack Engineer to join a fast-paced product engineering team working on a large-scale, high-traffic web and mobile platform. You will work within a mature production environment with real architectural complexity: web and mobile clients built in React and React Native, a GraphQL API layer, and a fleet of Node.js microservices communicating through domain events.
The team owns its features end-to-end, from the UI through the APIs down to the databases and the background jobs, and also maintains the supporting pieces around them: an analytics data stack (dbt + Snowflake + orchestration) and the CI/CD pipelines and observability that keep everything running. This is a hands-on, coding-heavy role.
The large majority of your time is full-stack product development in React, React Native, Node.js, and GraphQL.
Beyond that, you will also provide support to the analytics data platform (dbt, Snowflake, and pipeline orchestration) and to the delivery and DevOps layer (CI/CD pipelines, deployments, and logs/metrics investigation).
Responsibilities
Frontend (React / React Native)
Develop and maintain scalable web applications in React and TypeScript
Build and ship features for a production React Native (Expo) mobile app
Build reusable, accessible components and front-end libraries against an established design system
Optimize applications for performance and responsiveness across web and mobile
Integrate the UI layer with GraphQL and REST APIs, including authentication, error handling, and loading/empty states
Write and maintain unit and integration tests for UI components and application logic (Jest, React Testing Library)
Instrument features with typed product analytics (e.g. Segment / Typewriter-style tracking)
Backend (Node.js / GraphQL)
Design and implement GraphQL APIs (Apollo Server) and RESTful services in Node.js/TypeScript
Build and maintain microservices backed by MongoDB and Redis, integrated through a domain-event bus/message queue
Evolve GraphQL schemas and typed API contracts, and keep providers and consumers in sync using code generation
Write database migrations, background/scheduled jobs, and event producers and consumers
Write and maintain unit and integration tests for services, resolvers, and data access (Jest, Mocha)
Ensure system reliability, scalability, and maintainability; participate in production triage and incident resolution for the services the team owns
Delivery/DevOps
Use logging, metrics, and monitoring tooling to diagnose production issues and close observability gaps, including structured/JSON logging with a log aggregation platform, error tracking, and job/cron monitoring
Maintain CI/CD pipelines (Buildkite or equivalent): test parallelization, caching, secrets, and staged staging-before-production deploys
Work with Docker for local development and containerized deploys on AWS
Data platform
Extend and maintain transformation models in dbt on Snowflake, including incremental models, snapshots, tests, and documentation
Model raw event streams and third-party sources into clean, tested datasets that power reporting
Help keep pipeline orchestration healthy (Airflow / Dagster and scheduled dbt runs), including source-freshness checks and failure alerting
Ways of working
Ensure code quality through code review, automated testing, and engineering best practices
Collaborate with product managers, designers, and other engineers to define features, estimate effort, and evaluate technical trade-offs
Use AI-assisted development tools (Claude Code, Cursor, GitHub Copilot, etc.) to accelerate delivery while critically reviewing and validating generated code for correctness, security, and maintainability
Required Qualifications
5+ years of professional software engineering experience, with a strong full-stack or backend-leaning track record
Expert-level JavaScript (ES6+) and TypeScript
Strong hands-on experience with React, including hooks / functional components and state management
Production experience with React Native (Expo a plus), including building and maintaining a live mobile app
Strong Node.js backend experience: building and consuming GraphQL APIs (Apollo) and RESTful services, plus background/async processing
Experience designing and evolving GraphQL schemas and API contracts
Experience with MongoDB (or another document database)
Strong automated-testing discipline, including writing and maintaining unit and integration tests on both the front end and the back end (Jest, React Testing Library, Mocha), plus familiarity with end-to-end testing (Playwright or similar)
Proficiency with Git and modern collaborative workflows, code reviews, and CI/CD pipelines
Familiarity with Agile/Kanban delivery
Fluent English, written and spoken, with the ability to explain technical decisions and trade-offs to both technical and non-technical stakeholders
High autonomy and ownership: breaks down ambiguous problems, drives tasks to completion with minimal supervision, and surfaces risks and blockers early
Adaptable and curious: comfortable moving across unfamiliar parts of the stack when the work calls for it
Accountable and dependable in following through on commitments
Bachelor's degree in Computer Science, Software Engineering, or a related field, or equivalent practical experience.
Nice To Have Skills
Experience with Next.js and modern rendering strategies (SSR/SSG/ISR)
Experience with dbt and a cloud data warehouse (Snowflake preferred)
Experience with a workflow orchestrator such as Airflow, Dagster, or Prefect
Event-driven architectures and message queues (RabbitMQ/AMQP, Kafka, or a domain-events framework)
Monorepo tooling (Lerna/Nx/Yarn workspaces) and publishing shared internal libraries
Product analytics instrumentation with Segment or comparable typed-tracking tools
Headless CMS integrations
Observability tooling such as Datadog, OpenTelemetry, or CloudWatch
Search platforms (Algolia/Elasticsearch), payments (Stripe), and feature-flagging/experimentation platforms (Prismic)
Experience with GitHub Actions/Buildkite and mobile CI/CD (EAS, Fastlane)
Experience leveraging AI-assisted development tools (Claude Code, Cursor, GitHub Copilot) beyond code completion
Avenue Code reinforces its commitment to privacy and to all the principles guaranteed by the most accurate global data protection laws, such as GDPR, LGPD, CCPA and CPRA. The Candidate data shared with Avenue Code will be kept confidential and will not be transmitted to disinterested third parties, nor will it be used for purposes other than the application for open positions. As a Consultancy company, Avenue Code may share your information with its clients and other Companies from the CompassUol Group to which Avenue Code’s consultants are allocated to perform its services.

Work arrangement
No