Senior Software Developer Lisboa

About the Role

We are looking for an experienced Senior Full-Stack Developer to join our
- performing engineering Clients. This role is ideal for someone who enjoys taking ownership of large technical challenges, designing scalable systems, and contributing to both architecture and execution. You’ll work across the full web stack—React. js, Next. js, Node. js, My
SQL—while collaborating with
- functional teams to drive product and platform initiatives from inception to production.

As a senior engineer, you’ll not only build robust features but also help guide technical direction, champion code quality, and contribute to a culture of performance, reliability, and continuous improvement.

Key Responsibilities

• Lead the design, development, and optimization of scalable
  - stack applications using Next. js, React. js, Node. js, and My
  SQL.
• Drive architecture discussions and system design for new modules and features with an eye on scalability, modularity, and performance.
• Own
  -
  - end implementation — from planning to deployment — ensuring best practices in coding, testing, CI/CD, and documentation.
• Contribute to building performant RESTful APIs and cleanly integrating backend services with modular frontend components.
• Continuously improve client and
  - side performance, including TTFB, LCP, code splitting, caching, DB tuning, and Lighthouse score optimizations.
• Collaborate closely with design, product, Dev
  Ops, and other engineering teams to build
  - centric, scalable experiences.
• Review code, provide architectural guidance, and advocate for engineering excellence within the team.
• Use Docker and CI/CD pipelines (Jenkins) for deployments to AWS infrastructure in a microservices environment.
• Leverage AI developer tools to increase productivity and guide others in their effective usage.

Required Skills & Qualifications

• 4–7 years of professional experience in
  - stack web development, including recent experience in a senior or lead capacity.
• Advanced proficiency in Java
  Script (ES6+), React. js, Next. js (SSR, routing, data fetching), and Node. js.
• Strong experience with relational databases, particularly My
  SQL, including schema design and performance tuning.
• Familiarity with modern AI-powered developer tools (e. g. , Git
  Hub Copilot, Cursor, Tabnine, etc. ) and their application in team workflows.
• Proven ability to identify and debug performance bottlenecks across both frontend and backend by analyzing
  - level metrics (CPU, memory, I/O, logs, network latency, etc. ).
• Hands-on experience optimizing
  - side performance using techniques like bundle splitting, lazy loading, and Lighthouse auditing.
• Working knowledge of Google Analytics 4 (GA4) for measuring frontend performance and user interactions.
• Deep understanding of REST APIs, microservices communication patterns, error handling, and API versioning.
• Proficiency with Docker, CI/CD with Jenkins, and working knowledge of AWS services (EC2, S3, RDS, etc. ).
• Clear, maintainable coding style with experience in code reviews, testing frameworks (Jest, React Testing Library), and technical documentation.
• Comfortable working in
  - functional teams and independently owning complex features or refactors.

Preferred Qualifications

• Experience handling
  - region websites, performance optimization and data privacy/security standards.
• Experience with Big
  Query GA4 exports—writing queries to analyze usage trends, retention, conversion funnels, and performance issues.
• Experience with Dev
  Ops, observability (New Relic, ELK), or system reliability practices.
• Experience with API documentation tools like Swagger/Postman, and automated deployment pipelines.
• Knowledge of CDNs (like Cloudflare) and internationalization/localization strategies for web apps.

What You’ll Get

• The autonomy to architect systems, make technical decisions, and see your ideas shipped to production.
• A
  - paced,
  - savvy startup environment where your work directly impacts product and business outcomes.
• Opportunity to work with state of the art tech, modern,
  - focused Java
  Script stack.
• Opportunity to drive
  - functional initiatives and contribute to the technical direction of the platform.
• High ownership, real impact, and the satisfaction of building things that matter at scale.