# Senior Software Engineer, Backend (AI Agent Runtime)

**Company**: Cresta
**Location**: Canada (Remote)
**Work arrangement**: remote
**Experience**: senior
**Job type**: full-time
**Category**: Engineering
**Industry**: Technology

**Apply**: https://job-boards.greenhouse.io/cresta/jobs/4675293008
**Canonical**: https://yubhub.co/jobs/job_c76014f6-557

## Description

Build real-time AI agent infrastructure: Design and operate the stateful, low-latency runtime that powers voice and chat AI agents , from LLM streaming and conversation state management to graceful recovery and multi-channel support.

Solve distributed systems problems: Own session management across scaled-out workers , including affinity, checkpointing, crash recovery, and consistency under concurrent access.

Build a function execution platform: Own a serverless-style runtime where customers deploy custom logic , build orchestration, container lifecycle, autoscaling, and versioned rollouts.

Own developer experience and test infrastructure: Build CLI tools, local development environments, and test execution frameworks that let engineers iterate quickly and ship with confidence.

Raise the bar on production quality: Drive observability, incident response, and engineering best practices across the team.

We're looking for a senior software engineer with 5+ years of experience in infrastructure, platform, or systems work. You should have strong Python and Go skills, as well as a deep understanding of distributed systems, consistency, fault tolerance, state management, and concurrency.

Experience with Kubernetes and cloud-native infrastructure is also required. You should be able to build developer-facing tooling, such as CLIs, SDKs, local dev environments, or internal platforms.

A high bar for code quality, thorough testing, thoughtful code review, and sustainable engineering practices are essential. You should be comfortable operating what you build, on-call, incident response, and production ownership.

AI-native workflow is a must, and you should actively use LLMs and AI-assisted tools in your daily development.

## Skills

### Required
- Python
- Go
- Distributed systems
- Kubernetes
- Cloud-native infrastructure
- Developer-facing tooling
- Code quality
- Testing
- Code review
- Sustainable engineering practices

### Nice to have
- LLMs
- AI-assisted tools
- Real-time voice or streaming media systems
- Hands-on with LLM integration
- Serverless or function-as-a-service platforms
- Workflow engines
- Infrastructure-as-code and GitOps workflows