Middle Full-Stack Developer

About Us
Ruby Labs is a leading tech company that creates and operates innovative consumer products. We offer a diverse range of opportunities across the health, education, and entertainment industries. Our innovative teams are driving the future of consumer-led products, and we are always looking for passionate individuals to join us. Learn more about our story at: https://rubylabs.com/about-us/

About The Role
We are looking for a disciplined, highly autonomous Middle Next.js Developer to build and ship product features for one of our core D2C subscription products. You will own features end to end across a TypeScript monorepo - a Next.js App Router client, a Fastify + Payload CMS API on PostgreSQL, and Cloudflare Workers at the edge - from the moment you receive a task, through breaking it down, estimating, implementing, testing, and observability, to a clean release to production and confirmation that it works for real users.

This is a hands-on engineering role suited for someone who treats production as the standard, not the finish line. Half-tested code, silent failures, and unverified AI-generated output are not acceptable. The codebase is convention-heavy - a layered Feature-Sliced Design structure with strict import rules - and you are expected to work inside those conventions rather than around them. You are accountable for every task you take on and for every area of the product you touch: if it breaks, regresses, or stays half-finished, that is yours to see through. We expect maximum autonomy and real involvement in the product - you work independently within a sprint, communicate risks before they become blockers, and elevate architectural decisions to senior engineers rather than guessing.

Key Responsibilities

Feature Development

Build features across the Next.js client and the Fastify + Payload CMS backend according to product requirements

Write code that follows the team's Feature-Sliced Design layering, naming, and import conventions

Ship changes behind feature flags and A/B experiments, fully localized across every supported locale

Integrate third-party providers - billing, email/CRM, analytics - over REST APIs and webhooks

Quality & Reliability

Cover functionality with unit, integration, and e2e tests at the level the team expects

Run a thorough self-review before code review, and review teammates' code with the same rigor

Fix bugs and perform root-cause analysis for recurring issues

Optimize page and endpoint performance - rendering and caching strategy, database queries, bundle size

Security & Observability

Apply secure development practices: schema validation, access control, safe handling of secrets

Follow observability practices - structured logging, metrics, and alerts - using existing tooling

Collaboration

Break down, estimate, and ship your own tasks to production within the sprint - and stay accountable for them after release

Own the areas of the product you work in: their stability, performance, and follow-up fixes

Surface requirement clarifications, estimate changes, and risks early and in writing

Escalate complex architectural decisions and critical risks to senior engineers

Qualifications
Must-Have Experience

2+ years of commercial React experience, including 1+ year with Next.js (App Router, Server Components, route handlers, rendering and caching strategies) and solid TypeScript

Node.js backend experience on a typed HTTP framework (Fastify, Nest, or Express) with PostgreSQL - REST API design, schema migrations, integrations over REST and webhooks (signature verification, idempotency, retries) - plus a working understanding of HTTP/REST, auth mechanisms, and web security fundamentals

Hands-on with the modern client stack: TanStack Query, Zustand, React Hook Form + Zod, Tailwind CSS, and a React component library such as HeroUI, MUI, or shadcn/ui

Experience with a code-first headless CMS on PostgreSQL (Payload, Strapi, Directus, or equivalent) - collections, access control, generated types, migrations

Testing and delivery discipline: e2e tests (Cypress or Playwright) and unit/integration tests (Vitest or Jest), Git flow, code review, working with CI

Daily use of AI development tools (Claude Code or equivalents), including configuring them for a project - context, instructions, rules, MCP/integrations - with full ownership of the quality, security, and correctness of generated code

English - B1+

Leadership Attributes

Owns the outcome - takes a task from requirement to production without waiting to be pushed, and stays accountable for the result and the area it touches

Maximally autonomous and involved - needs a goal, not step-by-step instructions, and cares how the product performs, not just whether the ticket is closed

Verifies before trusting - treats AI output, thir