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# Senior Software Engineer

- **Company:** Aifi
- **Location:** Madrid, Spain
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), Unit Testing, C Sharp (Programming Language), Computer Engineering, Command-Query Responsibility Segregation (Software Development), Event-Driven Programming, Python (Programming Language), PostgreSQL, MongoDB, Node.Js, Standard Sql, TypeScript, Web Applications, Real Time Systems, ReactJS, Backend, Kubernetes, Information Technology, React Native, Front End Software Development, Event Sourcing, NestJS, Restful APIs, Domain Driven Design, Docker, Golang, Microservices
- **Published:** October 7, 2026
- **Apply:** https://www.recruit.net/job/senior-software-engineer-jobs/C7DA9B6A2674F414

## About the Role

* BS/MS in computer science or related field
 * 3+ years of experience as a Software Engineer (Backend)
 * 2+ years of experience using TypeScript
 * 2+ years of experience working in node. xhfqzwm js for web applications backend
 * Highly skilled in unit testing, experience with Jest testing framework
 * Highly skilled in RESTful API design and REST API usage
 * Proficiency with data modeling, static typing, and SQL
 * Proficiency in using Docker
 * Experience with event driven or real-time systems
 * Experience with TypeScript / JavaScript backend frameworks (e.G. NestJS)
 * Experience with Python, GoLang, or C#
 * Experience with Kubernetes
 * Experience with Postgres
 * Experience with Frontend Development (React, React Native) is a plus
 * Experience with Domain Driven Design, Event Sourcing and CQRS is a plus

Preferred Additional Qualifications

 * MS or PhD in Computer Science, Computer Engineering or a related field
 * Skilled in Kubernetes, experience with kustomize or helm
 * Experience with MongoDB
 * Experience with gRPC
 * Experience in e-commerce software, checkout processes, payments, virtual POS or other related systems

## Description

* Lead on optimizing our highly concurrent systems
 * Scale the store operating systems from small stores to gigantic venues
 * Make design decisions in the process of developing our core backend microservices
 * Work closely with app developers and product managers to understand the use cases that we need to cover and their potential bottlenecks
 * Work with deployment engineers to ensure that what you build goes as quickly as possible to the clients