Senior Software Engineer, Growth

Apollo.io is the leading go-to-market solution for revenue teams, trusted by over 500,000 companies and millions of users globally, from rapidly growing startups to some of the world's largest enterprises. Founded in 2015, the company is one of the fastest growing companies in SaaS, raising approximately $250 million to date and valued at $1.6 billion. Apollo.io provides sales and marketing teams with easy access to verified contact data for over 210 million B2B contacts and 35 million companies worldwide, along with tools to engage and convert these contacts in one unified platform. By helping revenue professionals find the most accurate contact information and automating the outreach process, Apollo.io turns prospects into customers. Apollo raised a series D in 2023 and is backed by top-tier investors, including Sequoia Capital, Bain Capital Ventures, and more, and counts the former President and COO of Hubspot, JD Sherman, among its board members. **This is a Permanent role ("Umowa o pracę") and not a B2B contract** As a Senior Software Engineer on the Growth team , you will be a critical part of our growing company, working at the intersection of engineering, product, marketing, and data science to accelerate product growth through rapid experimentation, data analysis, and scalable technical solutions. You’ll implement and drive best practices in technology, architecture, and process while optimizing funnels, automating growth loops, and shipping features that drive measurable impact. 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, enjoy working cross-functionally to solve hard problems, and strive for quality — obsessing over automation, performance, and squashing any bugs that sneak through. Our tech stack: Ruby/RoR, React.js, TypeScript, Redux, Node.js, Python, MongoDB, Elasticsearch, Ansible, Terraform, Grafana, Kibana, Docker, Kubernetes, AWS/GCP, GitHub Actions. Daily Adventures and Responsibilities Develop and execute engineering strategies that enable rapid experimentation and data-driven decision-making Collaborate cross-functionally with Product, Design, Marketing, Data Science, and Engineering to optimize key growth metrics and contribute to core product initiatives Architect and build scalable systems that support growth initiatives, such as onboarding flows, personalization engines, and viral loops Implement A/B testing and data instrumentation to ensure accurate tracking and measurement of experiments Leverage automation and machine learning to optimize user engagement, reduce churn, and personalize user experiences Produce clean, well-structured, well-documented code and implement pixel-perfect designs that work across browsers, per spec Help maintain code quality, organization, automation, and continuous delivery Ensure technical excellence through best practices in performance optimization, security, and scalability Effectively communicate development progress or blockers to the product lead, engineering manager, and other stakeholders Work effectively as part of a large global team; attend and engage in stand-ups, team meetings, and manager 1:1s Give and receive constructive feedback and praise Competencies Proactively acts without being told what to do; identifies areas of improvement and drives best practices to deliver high-quality, performant, scalable solutions Takes ownership over everything shipped Communicates effectively, clearly, and concisely — technical and non-technical, written and verbal — and actively listens to ensure understanding Helps teammates overcome obstacles, resolve blockers, and complete work; shares credit where due Actively seeks out and acts on feedback as a tool for growth Confident in owning their role and bringing creative ideas to users Excellent leadership and stakeholder management skills Comfort with ambiguity and a bias toward action; obsession with metrics (LTV, CAC, retention) and rapid iteration Skills & Relevant Experience Proven experience leveraging AI tools to enhance software development (code generation, debugging, productivity optimization), with fluency integrating AI-driven solutions into your workflow and a willingness to stay current with emerging AI technologies BS in Computer Science, or equivalent Minimum 5 years of industry experience in frontend or full-stack development, building large-scale applications Proficiency in JavaScript (ES6)/TypeScript, React, Redux, HTML, CSS, and at least one backend language (Ruby/RoR, Python, or Node.js) Experience with cloud infrastructure (AWS/GCP) and REST APIs Experience with analytics tools (Amplitude, Mixpanel, Google Analytics) and A/B testing platforms (e.g., Optimizely, LaunchDarkly, Segment) Familiarity with growth frameworks (e.g., Pirate Metrics, viral loops) Strong UX and product sense, with the ability to negotiate the right MVP Strong attention to detail; interest in building UI with performance, accessibility, and scalability in mind Nice-to-Haves Experience with growth at a startup or scaling product Knowledge of SEO, CRM tools (Braze, HubSpot), or marketing automation We are AI Native Apollo.io is an AI-native company built on a culture of continuous improvement. We’re on the front lines of driving productivity for our customers—and we expect the same mindset from our team. If you're energized by finding smarter, faster ways to get things done using AI and automation, you'll thrive here. Why You’ll Love Working at Apollo At Apollo, we’re driven by a shared mission: to help our customers unlock their full revenue potential. That’s why we take extreme ownership of our work, move with focus and urgency , and learn voraciously to stay ahead. We invest deeply in your growth, ensuring you have the resources, support, and autonomy to own your role and make a real impact . Collaboration is at our core—we’re all for one , meaning you’ll have a team across departments ready to help you succeed. We encourage bold ideas and courageous action , giving you the freedom to experiment, take smart risks, and drive big wins. If you’re looking for a place where your work matters, where you can push boundaries, and where your career can thrive—Apollo is the place for you. Learn more here!