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. 6 billion. 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.

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. YOUR ROLE & MISSION As a Senior 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 work across two high-impact domains: data platform architecture and integrations with distributed systems building the infrastructure that powers Apollo’s AI-driven internal products.

On the data side, you’ll organize and make sense of data at scale, working closely with our data engineering team to structure pipelines and enable intelligent product experiences. On the integrations side, you’ll own the connections layer and the distributed architecture that keeps Apollo reliably linked to the broader ecosystem at high throughput. You enjoy working cross-functionally to solve hard problems and make an impact.

At Apollo, you strive for quality and are obsessed with improving automation, squashing bugs, and investigating performance improvements and innovative ideas. You bring an AI-first mindset to everything you do, reaching for AI tools as naturally as any other part of your workflow and helping the team do the same.

RESPONSIBILITIES

Design and implement highly scalable backend services, data pipelines, and integration endpoints that perform reliably at high volume Gather product and engineering

Requirements

; write design documents and drive technical discussions to align cross-functional stakeholders Drive and lead the full software development lifecycle: product

, architecture, solution design, development, quality assurance, and maintenance Build systems with observability as a first-class concern proper monitoring, alerting, and dashboards so issues are caught before customers notice Mentor others on best practices and effectively share knowledge across the engineering team Communicate development progress clearly to product leads, engineering managers, and other stakeholders Be comfortable introducing new technologies and new ideas as required, including AI tools that accelerate your workflow and the team’s Navigate ambiguity and roadblocks proactively when a project hits a wall, you find a path forward and maintain cadence Work effectively as part of a large global team, attending scrum ceremonies, team events, and manager 1:1s Provide and respond to technical and behavioral feedback from managers and peers in written and verbal form COMPETENCIES Proactively acts without being told what to do; identifies areas for improvement and drives best practices to deliver high-quality, performant, and scalable solutions Develops services that a