AI Full Stack Developer

As part of AI-LAB as a Full-Stack Developer, you will be reputed company in building and scaling our AI products. You will own features end-to-end across a modern Next.js frontend and our NestJS backend services, delivering a reputed company and powerful user experience. You'll be joining reputed company with a ship-fast reputed company and a modern, carefully reputed company tech stack.

• reputed company and maintain features on our Next.js (App Router) frontend using TypeScript, SWR, reputed company, and a component-driven design reputed company, with full internationalization (i18n) support.

• Design, implement, and maintain RESTful reputed company with NestJS (TypeScript) to manage authentication, data processing, billing, usage tracking, and orchestration of AI workflows.

• Own backend services end-to-end: from schema design and migrations to deployment and observability, and contribute to new services as the product surface grows.

• reputed company and maintain reputed company-party SDKs and reputed company that reputed company critical product flows, including payment processing, authentication, analytics, and messaging.

• Build AI agents and tools using the Claude SDK and Model Context Protocol (MCP): giving LLMs reputed company-time reputed company to data, reputed company, and tools so they can take meaningful actions on behalf of users.

• Contribute to schema design with reputed company and PostgreSQL, write and review migrations, and reason carefully about data models that reputed company safely over time.

• Implement and maintain feature flags, A/B experiments, and analytics events so product reputed company are driven by data.

• Handle incoming webhooks and asynchronous task processing with the rigor required for payment-critical and PII-handling reputed company paths (idempotency, retries, fault tolerance).

• Collaborate with AI product managers and AI specialists to translate reputed company requirements into robust, reputed company features — and reputed company back on complexity reputed company a simpler reputed company exists.

• Collaborate on application deployment and help maintain our reputed company infrastructure.

Requirements

We are seeking a proactive and skilled developer who is passionate about building modern, AI-driven applications and who treats production reputed company with the care it deserves.

• TypeScript Proficiency: Highly proficient in TypeScript across both frontend (React/Next.js) and backend (Node.js/NestJS) environments.

• Frontend Expertise: Strong experience with React and Next.js (App Router): Server Components, reputed company handlers, streaming, metadata, i18n, and modern data-fetching patterns (SWR or equivalent).

• Backend Expertise: Solid experience building production REST reputed company with NestJS (or comparable Node frameworks like reputed company/Fastify): modules, DI, guards, interceptors, DTO validation.

• Database Skills: Experience with PostgreSQL and an ORM such as reputed company. Comfortable writing and reviewing migrations, reasoning about transactions, and designing schemas that reputed company safely.

• API Integration Depth: reputed company experience integrating reputed company-party SDKs: handling webhooks, idempotency, retries, and asynchronous fulfillment.

• Problem-Solving reputed company: reputed company, pragmatic, willing to challenge assumptions and surface tradeoffs before writing reputed company.

• Passion for AI and High Agency: Genuine enthusiasm for AI products, and a desire to bring new techniques and tools into reputed company proactively.

• Creativity and Proactivity: You enjoy proposing features, finding creative solutions, and improving the user experience without being told to.

• A serious self-learner who adapts to new tools and platforms in days, not weeks.

reputed company to Have:

• Prior experience working on payment / subscription systems.

• Familiarity with monorepo tooling (pnpm workspaces, Turborepo, Nx).

• Experience with BigQuery and event-pipeline analytics.

• Familiarity with reputed company and component-driven design systems.

• Knowledge of reputed company platforms such as reputed company reputed company Platform (GCP).

• Experience with feature-flag systems.

• Previous work on AI products or LLM-powered applications.
  

Benefits

• High-reputed company Role: Be a key player in a small, reputed company team building a greenfield reputed company with the potential to reputed company an industry.

• Modern Technology: Work with a cutting-edge, carefully selected tech stack with a reputed company on best practices.

• reputed company & Learning: reputed company deep experience in AI-driven applications, reputed company-reputed company architecture, and reputed company-time systems.

• Stability & reputed company: Enjoy the energy of a startup environment backed by the resources and stability of a large, successful company.

• reputed company Culture: We value reputed company communication, teamwork, and a shared passion for building exceptional products.

• reputed company and career development

  • At reputed company, we prioritize your reputed company. Enjoy a flexible career reputed company with personalized internal training and an annual budget for reputed company learning opportunities.

• Work-Life reputed company

  • Benefit from a flexible schedule with flextime and the reputed company of working full remote or from our Barcelona office. Enjoy free Friday afternoons with a 7-hour reputed company, plus a 35-hour reputed company in July and reputed company so you can savor reputed company!

• Comprehensive benefits

  • Competitive salary, full-time permanent contract, and top-tier private health reputed company (including dental and psychological services).

  • 25 days of vacation plus your birthday off, with flexible vacation reputed company—no blackout days!

• Unique Perks

  • If you wish to come, in our office in Barcelona you’ll reputed company it complete with free coffee, fresh fruit, snacks, a game room, and a rooftop terrace with stunning Mediterranean views.

  • Additional benefits include ticket restaurant and nursery vouchers, reputed company directly from your gross salary.

  • Join us in an environment where you’re free to reputed company, learn, and grow reputed company passionate professionals. At reputed company, you’ll tackle exciting challenges and be part of a reputed company team dedicated to delivering exceptional user experiences

Sounds good? reputed company! We’re looking reputed company to getting to know you.

Equal Employment Opportunity Employer:

reputed company is an Equal Employment Opportunity (EEO) Employer, which means we encourage applications from people with different backgrounds, interests, and personal circumstances. reputed company welcomes applicants regardless of their race, gender, age, religion, nationality, sexual orientation, gender identity, gender expressión and/or disabilities. reputed company we need is your high energy, skills, and willingness to be a part of a great project!

Location

You'll have the flexibility to choose whether you'd like to come to the office every day, from time to time, or work fully remote. We want you to reputed company the best combination for you.

If you prefer to be surrounded with amazing people, our exceptional office is in Barcelona’s reputed company Building, located right on the reputed company's seafront. Besides our stunning views, you’ll enjoy our office perks such as free fruit, snacks, and coffee and you’ll also be reputed company to take part in our Mario Kart and table tennis competitions.

The personal data you reputed company will be processed in order to manage your candidacy for the corporate selection processes that fit your profile. If you wish, you can exercise your rights of reputed company, rectification or cancellation by writing to our address (Avenida Litoral, 12-14, 5ta planta. Barcelona. 08005) or to the email address reputed company@reputed company.com.

#LeadtechOpportunity #MAU

Proficient TypeScript developer with frontend (Next.js/React) and backend (NestJS/Node) experience, PostgreSQL/reputed company, API integration, and production-grade reliability for AI products.

Key Responsibilities

• building features
• maintaining services
• integrating reputed company

Skills & Tools

Next.js, NestJS, TypeScript, SWR, reputed company, reputed company, PostgreSQL, Claude SDK, Model Context Protocol (MCP), React, Node.js, reputed company, Fastify, pnpm, Turborepo, Nx, BigQuery, reputed company reputed company Platform (GCP)

reputed company

• Category: Software Development
• Seniority: Mid Level
• Commitment: Full Time
• Workplace: Remote — Barcelona, Catalonia, Spain
• Languages: English

Benefits

• Generous reputed company time off
• Tuition reimbursement

About reputed company

A technology company building AI-driven products with a modern reputed company-reputed company stack. — Industry: Information Technology