---
title: 'Fullstack Software Engineer, Kafka at Aiven'
canonical: 'https://feeny.ai/job/fullstack-software-engineer-kafka-aiven-helsinki-jjzq55v4ynjp'
type: 'job'
last_seen: '2026-09-10'
---

# Fullstack Software Engineer, Kafka at Aiven

- **Company:** Aiven
- **Location:** Helsinki, Finland
- **Posted:** 2026-08-31
- **Last confirmed live:** 2026-09-10
- **Apply:** https://aiven.io/careers/job/4962384101?gh_jid=4962384101

## Job description

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.

## The Role

We're looking for a Fullstack Software Engineer to join our Kafka Ecosystem team. You'll build features end-to-end: production Python in the platform that orchestrates managed Apache Kafka® services across clouds, contributions to [Karapace](https://github.com/aiven/karapace) (our open-source Schema Registry and Kafka REST Proxy), and the React interfaces that put those features in front of users. Your main focus is Python; your reach extends from API design to the UI that ships with it.

## What You'll Do

- Extend and maintain Karapace: schema compatibility logic, REST Proxy features such as exposing message headers in produce and consume paths, OpenAPI schema coverage, and Confluent API compatibility
- Keep the connector ecosystem healthy: upgrades and releases of connectors like Debezium, JDBC, S3, BigQuery, and the OpenSearch® sink, security fixes, and changelogs
- Participate in design and code reviews, write well-tested code, and help shape technical direction
- Ship code reliably and often through CI/CD pipelines (Buildkite, GitHub Actions)
- Investigate and resolve production issues across the stack, from async Python application code down to Linux system behavior
- Contribute to technical planning within a small team where your input directly shapes the roadmap
- Own features end-to-end: design the API, build the async Python backend, and wire up the React/TypeScript views in our console
- Use AI coding tools as part of your daily workflow to speed up development

## What We're Looking For

Must have:

- Strong Python skills: you're comfortable with async/await patterns, understand event loop semantics, and write production-grade code with type annotations and tests
- Full-stack ability: you can contribute confidently to a React/TypeScript codebase and take a feature from backend to shipped UI
- Distributed systems fundamentals: you reason clearly about consistency, replication, and failure modes
- Familiarity with schema formats and evolution: Avro, JSON Schema, or Protobuf; you understand why schema compatibility matters
- Linux fundamentals: comfortable with process management and debugging at the OS level
- Fluent in AI-assisted development: you actively use AI coding tools (Claude Code or similar) in your daily workflow, including automating repetitive processes and building AI-assisted workflows
- Fluent English, written and verbal

Nice to have:

- Hands-on Apache Kafka® experience: consumer groups, offset management, and the group coordination protocol
- Kafka Connect and connector development: custom connectors, transforms, or converters
- Prior open-source contributions, on any project
- Experience with public clouds (AWS, GCP, Azure) and cloud-managed Kafka (MSK, Confluent Cloud, or Aiven for Apache Kafka®) or other cloud-native distributed systems
- Working Java knowledge, enough to contribute to Kafka Connect source/sink tasks
- Experience operating or extending a schema registry (Confluent or Karapace)
- Experience with observability tooling: distributed tracing, Prometheus metrics, structured logging

## Why This Role

- Open-source at the core. A significant part of your work ships publicly as open source. Your name goes on the commits.
- Deep technical problems. Multi-format schema compatibility, connector lifecycle orchestration at scale, and UIs that make both approachable. Not a typical backend role, and not a typical frontend role either.
- End-to-end ownership. You design it, build it, ship it, and see users work with it. No handoffs across three teams.
- Direct impact. The team is large enough to tackle ambitious problems and small enough that your technical judgement still shapes what gets built.
- Helsinki, hybrid. 3 days in the office per week.

Amazing! What’s next:

If you think Aiven is the place for you and that our[Values](https://aiven.io/careers) align with yours, send us your resume and we’ll get in touch!

Global Benefits:

Our global benefits are designed to help you thrive and grow, personally and professionally:

- Participate in Aiven’s equity plan.
- Balance work and life with our hybrid work policy.
- Choose the equipment you need to set yourself up for success.
- Use your Professional Development Plan budget for learning opportunities.
- Receive holistic wellbeing support through our global Employee Assistance Program.
- Inquire about our Global Time Off Commitment (Parental and Sick Leave, as well as Personal Time)
- Enjoy country-specific benefits for our global cast.

How to Recognize and Avoid Employment Scams:

There has been a rise in fake job postings used by scammers to get personal information. At Aiven, all of our emails relating to recruitment come from an @aiven.io, @greenhouse.io or @eu.greenhouse.io domain and all of our interviews are conducted by video call or in person.  Our interviews will never occur via text or chat. If you’re unsure of the legitimacy of a job opportunity/offer pertaining to Aiven, please don’t hesitate to reach out to us at recruitment@aiven.io.

Equal Opportunities:

Aiven provides equal employment opportunities to all qualified employees and applicants for employment without regard to age, gender identity, national or ethnic origin, religion, sexual orientation, physical and mental ability, marital and family status or without regard to any other similar personal attributes. Aiven complies with applicable local laws governing non-discrimination in employment in every location in which the company operates. This policy applies to all terms and conditions of employment, including recruiting, hiring, placement, promotion, termination, layoff, transfer, leaves of absence, compensation, training and any other terms and conditions related to employment.

At Aiven we are committed to providing reasonable accommodations for qualified individuals with disabilities or special needs in our working environment and job application procedures. We make all reasonable accommodations for persons with disabilities or who otherwise need support to thrive in the workplace. We are committed to continuously improving workplace accessibility. There is an option to request a discussion in the application process but if you have any questions before applying please write to us at recruitment@aiven.io.

## About Aiven

## Company Overview
- **One-liner**: Aiven provides an AI-ready, fully managed open-source data platform that lets organizations stream, store, and serve data across major cloud providers.
- **Entity Type**: Private (Series D; total funding $420M)
- **Headquarters**: Helsinki, Finland
- **Founded**: 2016
- **Founders**: Oskari Saarenmaa, Hannu Valtonen, Heikki Nousiainen

## Core Business
- **Primary industry/industries**: Cloud data infrastructure – open-source managed services (PostgreSQL, Kafka, Valkey, etc.)
- **Target customers**: B2B – from startups to Fortune 500 enterprises across over 60 countries
- **Mission statement**: To make open-source databases, search, streaming, and application infrastructure easily accessible to everyone on any cloud.

## Products & Services
- **Aiven Platform**: Unified control plane to deploy, manage, and govern open-source data services across AWS, GCP, and Azure (SaaS).
- **Managed Open Source Data Services**: Fully managed Apache Kafka, PostgreSQL, Valkey (Redis), OpenSearch, M3, and more – deployable in over 100 regions.
- **Security & Compliance**: End-to-end encryption, dedicated VMs, ISO 27001, SOC2, GDPR compliance.
- **DevOps-friendly tools**: API, CLI, Terraform provider, Kubernetes operator for infrastructure-as-code.
- **Observability**: Built-in integrations with Prometheus, Grafana, and third-party monitoring tools.
- **Aiven Startup Program**: Up to $100,000 in credits for early-stage startups.

## Market Standing
- **Valuation**: Unicorn status (valuation > $1B implied), last funding round in 2021 – exact figure not publicly disclosed.
- **Key Metric**: Annual revenue ~€65.1M (latest available), total funding $420M.
- **Notable Investors**: Lifeline Ventures, Earlybird Venture Capital, IVP, Atomico, World Innovation Lab.
- **Growth Signals**: 374 employees (+7.9% YoY); operating in 26 countries; acquired Klaw (2022) to add schema registry capabilities; strong hiring across engineering, sales, and product roles.

## Competitive Advantages
- **Open-source foundation**: Avoids vendor lock-in; community-driven innovation.
- **Multi-cloud native**: One platform works on AWS, GCP, and Azure – customers can choose or switch.
- **AI-ready platform**: Built to support streaming, storage, and serving for modern AI/ML workloads.
- **Developer experience**: API-first, CLI, Terraform support, and extensive documentation.
- **Enterprise compliance**: SOC2, ISO 27001, GDPR – trusted by regulated industries.

## Strategic Focus
- Accelerate the “AI-ready open source data platform” narrative.
- Expand geographic presence (new hubs in Austin, Toronto, Singapore, etc.).
- Deepen product ecosystem – managed Valkey, better analytics and search services.
- Scale go-to-market through partnerships and startup programs.

## Why Work Here
- **Culture**: Open-source ethos – “Think Sideways”, “Invent and Impress”, “Get it done, together”. Described as a “Cast of Crabs” – diverse, curious, and collaborative.
- **Work model**: Hybrid-friendly with offices in Helsinki (HQ), Berlin, Paris, London, Amsterdam, Singapore, Sydney, Auckland, Austin, Toronto.
- **Benefits**: Stock options for permanent employees, private health & dental, individual learning budget, access to e-learning platforms, coaching, and a company library.
- **Perks**: Free drinks, treats, and fruit in offices; flexible working hours.
- **Engineering culture**: Open source contributions, SRE excellence, autonomy with accountability.

## Sources
1. [aiven.io/about](https://aiven.io/about)
2. [aiven.io/careers](https://aiven.io/careers)
3. [linkedin.com/company/aiven](https://www.linkedin.com/company/aiven)
4. [crunchbase.com/organization/aiven](https://www.crunchbase.com/organization/aiven)

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