Software Engineer, Backend-leaning Full Stack or Backend

About the Role

Join Zapier's Workflow Zone as a Software Engineer on the Runner Team, where you'll be instrumental in scaling the core engine that powers our automation platform. This role offers the exciting opportunity to build robust, high-performance distributed systems that ensure reliable and consistent execution of millions of daily workflows.

Responsibilities

• Design, implement, and scale Zapier’s execution engine to support millions of daily task runs with high reliability and low latency.
• Optimize system performance through improved queuing strategies, latency reduction, and stronger fault tolerance.
• Architect and evolve core execution primitives that underpin reliable and observable automation at scale.
• Build resilient distributed systems on AWS, with a focus on throughput, failover, and degradation handling.
• Develop and refine sharding and queuing strategies to ensure task fairness and efficient load distribution across the system.
• Implement coordinated work-packing techniques to effectively manage third-party service limits and partner API throttling.
• Collaborate with infrastructure, product, and platform teams on system design, cross-cutting features, and long-term architecture.
• Participate in on-call rotations and own time-to-execution SLAs ensuring fast and reliable task initiation across workflows.

Requirements

• Strong backend experience with Python building reliable, scalable, and observable distributed systems.
• Experience with infrastructure observability tooling (e.g., Databricks, Looker, Grafana, Graylog), combining data engineering skills with a data-driven approach to reliability.
• Proven experience architecting, building, debugging, and operating distributed systems at scale.
• Familiarity with AWS primitives, including S3, SQS, Lambda, and RDS.
• Familiarity with relational databases like PostgreSQL or MySQL, and the ability to model, query, and optimize data effectively.
• Experience designing and consuming RESTful APIs, building event-driven systems, and working with data integrations across services.
• Proven ability to lead complex technical projects, owning design decisions, balancing tradeoffs, and guiding implementation.

About the Team

This is a foundational team at the platform layer, ideal for engineers who enjoy deep technical challenges and shipping resilient, high-scale services. You will work on foundational systems used by millions, helping users build smarter, more powerful automations, and collaborate with cross-functional teams in a high-ownership environment with clear user impact and fast iteration.