Ingénieur Full Stack/Ingénieure Full Stack Porto

Ingénieur Full Stack/Ingénieure Full Stack
Porto
Porto, Porto District, Portugal

Sanjow is a a european Saa
S group specialising in subscription-based digital services across Europe and the UK. Their mission: design robust, optimised, and scalable infrastructures that support rapid growth and foster experimentation.

They make life easier for individuals and businesses with turnkey online solutions , particularly in the travel sector — from flight
- ins to airport lounge access, as well as
- volume platforms for ticket purchases. They also operate in other areas such as gift cards and mobile
- ups , while constantly exploring new opportunities, especially in AI .

The name Sanjow comes from the combination of the Japanese word for “support” (sanjo) and “flow” — a nod to their DNA of providing smooth, efficient assistance.

With headquarters in Paris , an office in Lisbon and colleagues based over the world, Sanjow is a fast-paced international
- up where innovation and collaboration know no borders.

The mission

To join their new team of 3 developers building their own payment solution , Sanjow is looking for a highly motivated and talented Full Stack Developer (Node. js) .

They’re seeking someone with proven expertise — and genuine passion — for the e-commerce sector ,
- on experience in payments and subscriptions , and solid mastery of the Agile SCRUM methodology. This is a small,
- moving team, so be ready to roll up your sleeves and dive in!

You’ll work closely with product leadership and technical peers to design, build, and deploy a modern billing system that includes rebill logic, smart routing, retries, and deep integrations with multiple PSPs.

Your main missions will be:

• Architect and develop Sanjow’s Payment Box
• Implement payment features such as smart routing, retry logic, and direct PSP integrations
• Collaborate with Product and Data teams to define use cases and KPIs
• Build and maintain integrations with existing services and APIs
• Ensure high availability, traceability, and observability of transactions
• Help define best practices for testing, release cycles, and monitoring

Tech Stack:

• Languages: Type
  Script / Java
  Script
• Backend: Node. js, Express, Prisma (Nest
  JS is a plus)
• Frontend: React, Next. js
• Database: Postgre
  SQL, Redis
• Infrastructure: Render, Vercel, Git
  Hub
• Methodology: Agile (2-week sprints), CI/CD

Why choose Sanjow?

• Play a key role in one of their most strategic initiatives
• Enjoy high autonomy and ownership in a lean,
  - paced environment
• Build critical infrastructure from scratch
• Benefit from a flexible work culture and flat hierarchy

Who they’re looking for:

• 5+ years’ experience as a developer with strong skills in Type
  Script, Node. js , and relational databases
• Proven experience building payment systems , PSPs, or billing logic
• Confident building API backends and asynchronous workflows
• Strong focus on code quality and modular, testable design
• Autonomous,
  - driven, and
  - oriented
• Fluent in English (Portuguese is a strong plus)
• Bonus points for :
• Experience with smart retry logic, subscription lifecycles, or
  - MID routing
• Familiarity with master gateways such as Rebilly or Ixo
  Pay
• Interest in using AI tools to boost coding and development productivity

Recruitment Process

• Phone call with a recruiter from Eiquem
• First interview with the CTO
• Technical interview with the Tech Lead of the payments team
• Final interview with one of the cofounders