Senior Software Engineer - ClickHouse

About this role

<p>We’re a global team of over 400+ people, working together to push the boundaries of open-source technology and multi-cloud solutions. Our vision is to help developers, builders, and creators bring their ideas to life with speed and simplicity, by providing a cloud data platform that makes open-source databases, search, streaming, and application infrastructure easily accessible to everyone.&nbsp;</p> <h2>The Role</h2> <p>We're looking for a Senior or Staff Backend Engineer to anchor our small, focused ClickHouse team. You'll own hard technical problems end to end on the platform behind our managed ClickHouse service - from database internals and backup/restore correctness to the data engineering tooling that connects ClickHouse to the wider ecosystem.</p> <p>This is a role with real technical ownership. You'll write RFCs and design documents that change how we build, scope and lead multi-quarter initiatives, and influence the product roadmap for ClickHouse and its ecosystem - streaming ingestion, CDC, benchmarking, and analytics tooling. You'll also mentor the engineers around you and raise the bar for how the team works.</p> <p>We expect you to be equally comfortable designing a new architecture and diving into a production incident - reading ClickHouse source code, untangling a replication race condition, or root-causing a flaky distributed test.</p> <h2>What You'll Do</h2> <ul> <li>Design and lead major platform initiatives: think coordination-service migrations (ZooKeeper → ClickHouse Keeper), backup/restore architecture, cluster topology, sharding, and node lifecycle management</li> <li>Build data engineering tooling around ClickHouse - streaming ingestion pipelines (Kafka → ClickHouse, Postgres → ClickHouse), schema conversion and evolution, integration frameworks, and fault-isolation between data sources</li> <li>Own the ClickHouse version lifecycle: qualify new LTS releases, diagnose upstream regressions, and take releases from early availability to GA</li> <li>Debug deep into the stack - ClickHouse internals (replication, access control, MergeTree, materialized views), distributed coordination, object storage (S3/GCS/Azure), DNS and networking, TLS</li> <li>Write RFCs and drive architectural decisions that extend beyond the team, including security and infrastructure changes</li> <li>Influence the roadmap: scope epics, break down initiatives into deliverable work, and shape what the team builds next - including commercial aspects like plans, sizing, and capacity</li> <li>Mentor engineers on the team through design reviews, code reviews, and pairing - multiply the team, don't just add to it</li> <li>Keep the lights on with pride: production incident response, observability improvements, CI performance, and test reliability are part of the craft</li> </ul> <h2>What We're Looking For</h2> <p><strong>Must have:</strong></p> <ul> <li><strong>Expert Python development skills</strong> - you write clean, production-grade async Python and have architected substantial systems with it, including decomposing large codebases into well-factored components</li> <li><strong>ClickHouse experience</strong> - operating it at scale, query optimization, or upstream contributions</li> <li><strong>C++</strong> - ability to read and contribute to database engine code</li> <li><strong>Deep database internals knowledge</strong> - replication, access control, storage engines, backup/restore semantics; you're comfortable reading database source code (ClickHouse is C++) to root-cause behavior</li> <li><strong>Distributed systems depth</strong> - consensus/coordination services (ZooKeeper, Keeper), race conditions, cluster topology, and the failure modes of services running across nodes, AZs, and regions</li> <li><strong>Data engineering experience</strong> - streaming pipelines, Kafka, schema management (Avro or similar), and the operational realities of moving data between systems reliably</li> <li><strong>Strong Linux and cloud fundamentals</strong> - object storage (S3-compatible), networking/DNS, TLS/certificates, systemd-level debugging</li> <li><strong>Track record of technical leadership</strong> - RFCs or design docs you've authored, multi-quarter initiatives you've scoped and led, engineers you've mentored</li> <li><strong>Product sense</strong> – you can connect engineering decisions to customer impact, pricing, and roadmap priorities</li> <li><strong>Experience with AI coding tools </strong>- you actively use AI-assisted development and help others get the most from it</li> <li><strong>Fluent English </strong>– written and verbal</li> </ul> <p><strong>Nice to have:</strong></p> <ul> <li>CDC and analytics ecosystem experience - Debezium-style pipelines, Iceberg, lakehouse formats</li> <li>Benchmarking and performance engineering - capacity planning, sizing methodology</li> <li>Security engineering exposure – certificate management, access-control models</li> </ul> <h2>Why This Role</h2> <ul> <li><strong>Real ownership.</strong> The team is small (you plus two engineers) - your designs, RFCs, and roadmap input directly determine what gets built.</li> <li><strong>Genuine depth.</strong> Database internals, distributed coordination, streaming data pipelines, and backup correctness - not CRUD apps.</li> <li><strong>Ecosystem scope.</strong> You shape not just the managed service but the data engineering tooling around ClickHouse - ingestion, CDC, benchmarking, integrations.</li> <li><strong>Modern tooling.</strong> Strict type checking, automated formatting, security scanning, and AI-assisted development are the norm.</li> <li><strong>Helsinki-based, hybrid.</strong> The team is in the office regularly; you'll work closely together.</li> </ul> <h3><strong>Amazing! What’s next:</strong></h3> <p>If you think Aiven is the place for you and that our<a href="https://aiven.io/careers"> Values</a> align with yours, send us your resume and we’ll get in touch!</p> <h3><strong>Global Benefits:</strong></h3>