Senior Backend Engineer (m/f/d) - Agent SDK
voize · Remote · Berlin · Dortmund · Göttingen · Hannover · Munich · Cologne · Hamburg ·
COMPENSATION
€•• – ••k
Listed on the employer's job board (Ashby)
- Senior Backend Engineer
- Kotlin + JVM
- Hybrid (Germany)
- Stock options included
- 30 vacation days
Join voize as a Senior Backend Engineer to own the Agent SDK, the Kotlin foundation powering AI companions for frontline workers. You will shape the runtime, define client-facing contracts, and ensure that adding new agents becomes increasingly efficient for feature teams.
The team combines advanced technology with social impact, backed by significant Series A funding. You will work on identity layers, telemetry integration, and testing frameworks to support over 200,000 users across 2,000+ facilities.
What you'll do
- Build and maintain the Agent SDK as an internal product with its own roadmap
- Design runtime and client-facing contracts for consuming teams
- Implement identity layers so agents operate with real user identities
- Integrate default telemetry, error reporting, and anonymization
- Create test kits and architecture tests to protect runtime internals
- Manage ecosystem changes like Koog version bumps and format compatibility
What you'll need
- Several years of production backend experience on the JVM
- Proficiency in Kotlin, Java, Scala or similar languages
- Experience designing APIs or SDKs where the contract is the product
- Background in building and maintaining stable integrations
- Strong focus on testing and observability in software development
- Interest in AI agent systems, orchestration, and evaluation
Stack
- Kotlin
- JVM
- Koog
How you'll work
- Hybrid setup with office in Berlin or remote within Germany
- Flexible working hours
- Regular team events and company off-sites
What you get
- Stock options
- 30 vacation days plus birthday off
- Germany Transport Ticket
- Urban Sports Club membership
- Access to learning platforms like Blinkist and Audible
- Free language courses