99Tech ★ 3.7

Fullstack Engineer (Claude)

About the Job

99Tech provides next-generation MarTech services. Our modular platform enables companies around the world to unlock new revenue opportunities and massively scale their business.

We are accelerating our expansion in R&D and product development. We offer an exciting and challenging environment where you will grow and learn. If you are passionate about delivering a marketing ecosystem that is innovative, secure and intuitive, this role could be for you.

As a Full-Stack Engineer, you will work closely with product managers, architects, and engineers to evolve the MarTech platform — from backend APIs to polished frontend experiences.

You will also be expected to leverage AI tools (e.g., Claude Code) intentionally and skillfully — as a force multiplier, not a crutch.

Responsibilities

• Engineer backend systems and RESTful APIs using Node.js (Express).

• Build responsive, performant frontend interfaces using React + TypeScript.

• Design and implement PostgreSQL schemas that support complex product requirements.

• Write clean, testable, well-documented code, and help hold that standard across the team.

• Use AI tools to accelerate development, debug, and solve architecture problems — while validating outputs.

• Analyze, propose, and deploy relevant technologies to meet product requirements.

• Collaborate across teams with clear technical communication in English.

Requirements

Must-have

• Ability to effectively use Claude Code for software development and testing

• Solid experience with Node.js and one of Express / Fastify / Hono.

• Proficiency in React with TypeScript (hooks, state management, component design).

• Strong understanding of PostgreSQL (schema design, indexing, query optimization).

• Familiarity with REST API design and HTTP fundamentals.

• Understanding of authentication patterns (JWT, sessions, OAuth basics).

• Strong advocate of code quality, testing, and craftsmanship.

• Communicates clearly in English.

Nice-to-have

• Experience with AI ecosystem and tools, like OpenClaw, MCP, …

• Experience with Redis (caching, pub/sub, rate limiting).

• Familiarity with Docker and containerized local dev environments.

• Exposure to queue systems (BullMQ, RabbitMQ, SQS).

• Experience with frontend data fetching patterns (React Query, SWR).

• Knowledge of CI/CD pipelines.

Mindset (non-negotiable)

• You take ownership.

• You use AI tools intentionally and skillfully and truly understand the code that AI writes.

• You care about the user experience, not just making the test pass.

• Newbies are welcomed if they can complete the code challenge.

What we evaluate

• Backend correctness and business rules

• API design (conventions, error handling)

• Frontend quality (UX, loading/error states, component structure)

• Code quality (readability, separation of concerns)

• AI collaboration (judgment, transparency)

• Testing (meaningful coverage and rationale)