Fullstack Engineer IC2

About Addi

We are a leading financial platform, building the future of payments, shopping, and banking—a world where consumers and merchants can transact effortlessly and grow together. Today, we serve over 2 million customers and partner with more than 20,000 merchants, making Addi Colombia’s fastest-growing marketplace.

With a state-of-the-art, technology-first approach, we provide banking solutions (deposits, payments, unsecured credit) and commerce services (e-commerce, marketing), bridging the financial gap for millions and redefining how people experience financial freedom. As the country’s leading Buy Now, Pay Later provider, we have secured regulatory approval to operate as a bank, unlocking even greater opportunities for our customers. In the past year, we have also achieved profitability, reinforcing the strength of our business model and our ability to scale sustainably.

Our mission has earned the trust of world-class investors, including Andreessen Horowitz, Architect Capital, GIC, Goldman Sachs, Greycroft, Monashees, Notable Capital, Quona Capital, Union Square Ventures, Victory Park Capital, and more, who back our vision for the future. With their support, we are not just growing—we are transforming Latin America’s financial ecosystem and shaping the next generation to shop, pay, and bank in Colombia.

But what truly sets us apart is how we build. We are a conscious company, driven by deep experience in scaling technology, services and products, and we live by our values every day.

About the Role

This is where you come in. Below, you’ll find what this role is all about—the impact you’ll drive, the challenges you’ll tackle, and what it takes to thrive at Addi. If you’re ready to be part of something big, keep reading.

What you will do

• Take end-to-end ownership of features, from frontend user interfaces to backend APIs and database design.

• Build modern, responsive web applications using React and Next.js with TypeScript, leveraging server-side rendering (SSR), static site generation (SSG), and API routes.

• Develop robust backend services and APIs using Node.js and TypeScript, ensuring scalability, security, and performance.

• Design and implement database schemas, optimize queries, and manage data persistence using SQL and NoSQL databases (PostgreSQL, MongoDB, Redis).

• Write clean, maintainable, and well-tested code with comprehensive unit, integration, and end-to-end tests.

• Collaborate with designers to implement pixel-perfect, accessible, and performant user interfaces that deliver excellent user experiences.

• Work closely with product managers to understand requirements, propose technical solutions, and balance feature delivery with technical excellence.

• Deploy features to production using modern CI/CD pipelines and infrastructure tools.

• Participate in on-call rotations to ensure system reliability and rapid incident response.

• Contribute to technical discussions, code reviews, and architectural decisions that shape the platform's evolution.

• Share knowledge with the team through documentation, pair programming, and technical presentations.

What we’re looking for

• Proven software development experience

  • Minimum of 4-5 years of experience building and shipping full-stack web applications in production environments.

  • Strong track record of delivering end-to-end features that balance user experience with technical excellence.

  • Experience working in agile, cross-functional teams with product managers, designers, and other engineers.

• Strong Technical Proficiency

  • Frontend: Deep expertise in TypeScript, React (hooks, context, performance optimization), and Next.js 13+ (App Router, Server Components, SSR/SSG, API routes). Experience with modern state management (Zustand, Redux, React Query) and styling approaches.

  • Backend: Extensive experience building scalable services with Node.js and TypeScript. Proven ability to design RESTful APIs and/or GraphQL services. Proficiency with SQL (PostgreSQL) and NoSQL (MongoDB, Redis) databases, authentication (JWT, OAuth), and asynchronous programming patterns.

  • Testing: Strong experience with unit, integration, and end-to-end tests using Jest, Vitest, React Testing Library, Playwright, or Cypress.

  • DevOps: Experience with Docker, cloud platforms (AWS, GCP, Azure), CI/CD pipelines, and deployment strategies.

  • Nice to have: Kubernetes, infrastructure as code, serverless architectures, and observability tools.

• Outstanding cross functional collaboration

  • Excellent communication skills, with the ability to explain complex technical concepts to both technical and non-technical stakeholders.

  • Comfortable working asynchronously in a remote or distributed team environment.

  • Proven ability to collaborate effectively with designers, product managers, and other engineers.

• Demonstrates exceptional initiative

  • Proactive in identifying problems, proposing solutions, and driving initiatives to completion with minimal supervision.

  • Strong prioritization skills, balancing immediate business needs with long-term technical health.

  • Demonstrates ownership mentality, taking responsibility for the entire lifecycle of features from conception to production support.

• Strong business acumen

  • Understanding of how technical decisions impact business outcomes and user value.

  • Ability to balance technical perfectionism with pragmatic delivery in a fast-paced environment.

  • Ideally experience in fintech, product companies, or high-growth startups.

• AI and Technical Innovation

  • Continuously learns and applies emerging AI technologies to accelerate development and enhance problem-solving.

  • Shares insights about modern development practices, tools, and patterns with the team, encouraging thoughtful experimentation and fostering a culture of continuous improvement.

Why join us?

• Work on a problem that truly matters – We are redefining how people shop, pay, and bank in Colombia, breaking down financial barriers and empowering millions. Your work will directly impact customers' lives by creating more accessible, seamless, and fair financial services.

• Be part of something big from the ground up – This is your chance to help shape a company, influencing everything from our technology and strategy to our culture and values. You won’t just be an employee—you’ll be an owner

• Unparalleled growth opportunity – The market we’re tackling is massive, and we’re growing faster than almost any fintech lender at our stage. If you’re looking for a high-impact role in a company that’s scaling fast, this is it.

• Join a world-class team – Work alongside top-tier talent from around the world, in an environment where excellence, ownership, and collaboration are at the core of everything we do. We care deeply about what we build and how we build it—and we want you to be a part of it.

• Competitive compensation & meaningful ownership – We believe in rewarding our talent. You’ll receive a generous salary, equity in the company, and benefits that go beyond the basics to support your growth.

How the hiring process looks like

We believe in a fast, transparent, and engaging hiring experience that allows both you and us to determine if there's a great fit. Here’s what our process looks like:

• Step 1: People Interview (30 min)
  A conversation with a recruiter to get to know you, your experience, and what you're looking for. We’ll also share more about Addi, our culture, and the role.

• Step 2: Initial Interview (90 min)
  In this stage, we’ll dive deeper into your technical background and problem-solving approach. You’ll discuss how you apply good engineering practices, handle feedback, and reason through real challenges as part of a collaborative team. You’ll also take part in a live coding session, where you’ll work through a practical problem and explain your thought process as you code.

• Step 3: Technical Challenge (6 Days)
  You’ll receive a take-home challenge designed to understand how you think and code. We’ll be looking for clean, well-documented, and functional work that demonstrates good practices, testing, and clear reasoning behind your decisions.

• Step 4: On-site Interview (60 min)

  You’ll present your take-home exercise and walk us through your implementation. We’ll discuss your design choices, testing, and error handling, while also exploring how you communicate your ideas and respond to feedback in real time.

• Step 5: Co-Founder Interview (30 min)

  In this final stage, you’ll meet a member of our leadership team to talk about Addi’s values, culture, and mission. It’s an opportunity to ensure that our goals and vision align, and that this role feels like the right next step for you.

We value efficiency and respect for your time, so we aim to complete the process as quickly as possible. Our goal is to make this experience insightful and exciting for you, just as much as it is for us. Regardless of the outcome, we are committed to always providing feedback, ensuring that you walk away with valuable insights from your experience with us.