Mid-Senior Software Engineer
Summary
Smadex is hiring a Mid-Senior Software Engineer in Barcelona to join an eight-person team maintaining and evolving a real-time bidding (OpenRTB) auction system. Day-to-day work means building features with Node.js and Java, testing in staging, monitoring deployments, and owning services end-to-end ('you build it, you run it').
We're looking for a knowledgeable Mid-Senior Software Engineer who enjoys solving complex technical challenges and building reliable, high-quality software for real-time systems.
👥 The team
Join a collaborative core engineering team of eight experienced engineers responsible for maintaining and evolving a real-time bidding (OpenRTB) auction system. The team values knowledge sharing, autonomy, and continuous professional growth while tackling complex engineering challenges.
🎯 Responsibilities
- Design, develop, and implement new features for core products using Node.js and Java
- Write clean, efficient, and testable code
- Test work locally and in a sophisticated staging environment
- Monitor deployments and help maintain the stability, reliability, and performance of production systems
- Participate in code reviews and contribute to technical and architectural decisions
- Collaborate in an agile environment, including planning and progress reporting
- Take ownership of work across the core platform following a “you build it, you run it” approach
🛠️ Requirements
- Bachelor’s degree in Computer Science or a related technical field
- 2–4 years of experience in a software engineering role
- Hands-on experience with Java or Node.js
- Solid theoretical knowledge of data structures, algorithms, and software design principles
- Passion for technology and eagerness to learn and grow professionally
- Excellent written and spoken English communication skills
- Proficiency with Linux, Git, Docker, and Docker Compose
- Experience with testing tools and modern CI/CD frameworks
➕ Nice to have
- Experience with key-value stores and in-memory databases such as Redis or Memcached
- Familiarity with cloud environments, particularly AWS
🧰 Technology stack
- Languages: Node.js, Java, Bash, Python
- Databases: MySQL
- Cloud and DevOps: AWS, Jenkins, Docker
- Tools: Git, Jira, Notion
🤗 What we offer
- Work with a highly motivated, dynamic team
- Great compensation package
- Flexible hours
- Monthly meal voucher allowance through Ticket Restaurant
- Monthly gym allowance with a choice between DiR and Wellhub
- Access to LinkedIn Learning and training opportunities
- Monthly TGIF events
- Regular team-building events
- A friendly, collaborative work environment with talented marketers and engineers from more than 40 countries
Must-have skills: Node.JS, Java.
Nice-to-have skills: Unit Testing, Jenkins, Cloud Platform.
Required languages: english (level 4/5).
Open only to candidates already eligible to work in the EU.