Distributed Systems Engineer

Work on Windmill's **Rust backend** - the execution engine, workers, language runtimes, API layer, and infrastructure that powers thousands of production deployments. * **Execution engine**: scheduling, job queues, worker orchestration, flow execution with branching, parallelism, retries, and error handling. * **Language runtimes**: maintain and extend sandboxed runtimes for Python, TypeScript, Go, Bash, SQL, and more. * **Performance & reliability**: profiling, optimization, resource management.

Our users run mission-critical workloads - correctness and uptime matter. * **Infrastructure**: PostgreSQL schema design, caching, networking, deployment tooling. ## **Who we're looking for** **This is a senior role.** We're looking for someone who has operated distributed systems at scale and can teach us from day one - showing us PostgreSQL patterns, distributed systems techniques, and architectural improvements we haven't considered yet. * Proven experience building and operating **distributed systems at scale** - not theoretical, you've done it in production * Deep **PostgreSQL** expertise - query optimization, schema design, concurrency control, partitioning, replication.

You know what breaks at scale and how to fix it. * Strong systems programming skills - **Rust** experience strongly preferred, otherwise C/C++ with willingness to switch * You bring opinions and techniques from previous infrastructure work that will make Windmill better immediately * You enjoy hard infrastructure problems and care about correctness ### **Example projects in your first 3 months** * Redesign the job queue to handle bursty workloads with thousands of concurrent jobs without degrading scheduling latency * Implement a new worker orchestration strategy that improves resource utilization across heterogeneous deployments (2 to 600 workers) * Optimize critical PostgreSQL queries and schema for customers with millions of completed jobs - partitioning, indexing, vacuum tuning * Add a new language runtime (e.g., Java, C#) with proper sandboxing, dependency management, and execution feedback * Build observability tooling - distributed tracing across the flow execution engine to diagnose slow or failing steps in production ## **Offer details** **Location**: Paris hybrid (\~3 days/week) or remote within France **Contract**: Full-time / CDI **Salary**: €60K–€90K gross + top of market for level + 20% bonus on collective milestones