Backend Software Engineer
Cognism
WHO ARE WE
Cognism is the leading provider of European B2B data and sales intelligence. Ambitious businesses of every size use our platform to discover, connect, and engage with qualified decision-makers faster and close more deals. Headquartered in London with global offices, Cognism’s contact data and contextual signals are trusted by thousands of revenue teams to eliminate the guesswork from prospecting.
Role Overview
We are looking for a Senior Backend Engineer who thrives on solving complex problems, has a strong product mindset, and is passionate about building scalable and resilient backend systems. You bring proven backend development experience, preferably with Scala, and excel at designing robust architectures that serve high-growth platforms. You're comfortable navigating ambiguity, managing technical debt, and continuously improving code quality through testing and best practices.
You’ll work closely with Product Managers, Designers, and fellow Engineers to translate product requirements into scalable and maintainable backend solutions. Your contributions will directly impact our platform's performance, scalability, and long-term technical health.
Responsibilities
- Build Scalable Applications: Lead the design, implementation, and optimization of scalable and secure backend services and APIs.
- Mentor & Elevate the Team: Provide technical guidance and mentorship to team members, fostering a culture of engineering excellence.
- Reduce Technical Debt: Identify and address technical debt to improve long-term maintainability and performance.
- Own Testing Strategy: Develop and advocate robust automated tests (unit, integration, end-to-end) to ensure backend stability and performance.
- Drive Engineering Excellence: Set and uphold high coding and testing standards, ensuring system reliability and long-term maintainability.
- Collaborate Cross-Functionally: Partner with cross-functional teams including Product, Design, and DevOps to deliver impactful features.
- Promote Continuous Improvement: Advocate for best practices and continuous improvement in our development lifecycle and infrastructure.
Our Tech Stack
- Primary Backend Language: Scala
- Other Backend: MongoDB, SingleStore, RabbitMQ, Kafka
- API: REST
- Infrastructure: AWS, Coralogix, Grafana
Requirements
- Experience: 6+ years of backend development experience with a proven track record of delivering scalable products in high-growth production environments
- Languages: Proficiency in Scala or a similar strongly typed, object-oriented or functional language.
- Architecture & Scaling: Experience building high-availability, distributed systems at scale. Understanding of SaaS business models and architecture is a plus.
- Cloud-Native Mindset: Experience with AWS services such as Lambda, S3 , API Gateway, ECS, and EC2.
- Software Engineering Craftsmanship: CI/CD, testing, clean code, and maintainable service design.
- Technical Leadership: Proven experience mentoring engineers and guiding architectural decisions.
WHY COGNISM
At Cognism, we’re not just building a company - we’re building an inclusive community of brilliant, diverse people who support, challenge, and inspire each other every day. If you’re looking for a place where your work truly makes an impact, you’re in the right spot!
Our values aren’t just words on a page—they guide how we work, how we treat each other, and how we grow together. They shape our culture, drive our success, and ensure that everyone feels valued, heard, and empowered to do their best work.
Here’s what we stand for:
✅ We Are Nice! We treat each other with respect and kindness (because life’s too short for anything else).
🤝 We Are Collaborative. We’re in this together—great things happen when we work as one.
💡 We Are Solution-Focused. Every challenge is just an opportunity in disguise.
💙 We Are Understanding. We empower and support each other to do our best work.
🏆 We Celebrate Individual Contributors. Every role matters, and so do you!
At Cognism, we are committed to fostering an inclusive, diverse, and supportive workplace. Our values—Being Nice, Collaborative, Solution-Focused, and Understanding—guide everything we do, and we celebrate Individual Contributors. We welcome applications from individuals typically underrepresented in tech, so if this role excites you but you’re unsure if you meet every requirement, we encourage you to apply!