Senior Backend Engineer

Poland Posted on February 7, 2026

Job Description

Senior Backend Engineer
Apollo.io

This is a Permanent role ('Umowa o pracę') and not a B2B contract

YOUR ROLE & MISSION

As a Senior Backend Software Engineer, you will be a critical part of our growing company, working on a cross-functional team to implement best practices in technology, architecture, and process. You'll have the chance to work in an open and collaborative environment, receive and give hands-on mentorship and have opportunities to grow and accelerate your career. You love both learning and teaching. In this role, you will be interfacing with design, front-end, analytics, as well as teams outside of Engineering. You enjoy working cross functionally to solve hard problems and make an impact. At Apollo, you strive for quality, and are obsessed with improving quality, automation, and squashing any bugs that sneak through. You have a drive to constantly investigate performance improvements and innovative ideas.

Our tech stack: Ruby/RoR, React.js, Typescript, Redux, MongoDB, Elasticsearch, Ansible, Terraform, Grafana, Kibana, Docker, Kubernetes, GCP, GitHub Actions.

DAILY ADVENTURES & RESPONSIBILITIES

Design and implement highly scalable backend endpoints

Gather product requirements and write design docs to satisfy product needs

Drive/Lead full lifecycle of software development: product requirements, architecture, solution design, development, quality assurance, and maintenance

Mentor others on best practices and effectively share knowledge

Ability to effectively communicate development progress to the product lead, engineering manager, and other stakeholders

Be comfortable introducing new technologies and new ideas as required

Work effectively as part of a large global team

Attend and engage in scrum ceremony meetings, team parties, and manager 1:1s

Provide feedback to co-workers in written and verbal form and respond to technical and behavioral feedback from managers and peers

COMPETENCIES

Proactively acts without being told what to do. Able to identify areas of improvement and driving best practices to deliver high quality, performant, and scalable solutions

Develops services that are highly available and scalable with proper monitoring and alerting in place

Able to up-level the team by sharing knowledge and best practices with the engineering team

Able to deal with ambiguity

Ownership of projects from start to finish. Just because the project has been deployed doesn’t mean it’s done

Organized and able to effectively plan and breakdown large projects into smaller tasks that are easier to estimate and deliver

Lets others speak and seek to understand their viewpoints

A creative and innovative problem solver & previous experience working in an agile, startup environment

Confident in owning your role, and bringing creative ideas to the hands of our users

QUALIFICATIONS

Minimum 5 years of industry experience in backend development, at least 1-2 years in senior positions, developing large-scale applications

Experience developing distributed web applications

Your code is comprehensible, well-structured, highly performant

Experience with database modeling (SQL or NoSQL both OK)

Experience with using and designing RESTful services

Strong knowledge of computer science fundamentals, including data structures, algorithms, and object-oriented design

Proven experience leveraging AI tools to enhance software development processes, including code generation, debugging, and productivity optimization. Candidates should demonstrate fluency in integrating AI-driven solutions into their workflows and a willingness to stay current with emerging AI technologies

Proven experience leveraging AI tools to enhance software development processes, including code generation, debugging, and productivity optimization. Candidates should demonstrate fluency in integrating AI-driven solutions into their workflows and a willingness to stay current with emerging AI technologies

Must have: Communication Skills, Problem Solving, Proactivity, Team Player, Listening Skills, Creativity and Innovation, Organization and Planning, Dealing with Ambiguity, Ownership of projects from start to finish, Distributed Web Development

Nice to have: BS or MS degree in Computer Science, Computer Engineering or similar, GCP, Kubernetes, Docker, Mongo, Redis, Ruby on Rails, Microservices, Machine Learning

About Apollo.io

Apollo.io combines a buyer database of over 210M contacts and powerful sales engagement and automation tools in one, easy to use platform. Trusted by over 160,000 companies including Autodesk, Rippling, Deel, Jasper.ai, Divvy, and Heap, Apollo has more than one million users globally. By helping sales professionals find their ideal buyers and intelligently automate outreach, Apollo helps go-to-market teams sell anything. Celebrating a $100M Series D Funding Round 🦄

Industry: Software Development