> Markdown version of [/jobs/ext/2716113-full-stack-software-engineers](https://www.wearedevelopers.com/jobs/ext/2716113-full-stack-software-engineers). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # full-stack software engineers - **Company:** Mucho Gusto AI, Inc. - **Location:** San Jose, CA, United States - **Experience:** Expert - **Salary:** $163,000.0 - $204,000.0 - **Contract:** Permanent contract - **Skills:** Microsoft Access, JavaScript (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Acceptance Test-Driven Development, Software Debugging, Ruby on Rails, Ruby, Software Engineering, ReactJS, Large Language Models, Multi-Agent Systems, Backend, Virtual Agents - **Published:** September 4, 2026 - **Apply:** https://startup.jobs/staff-software-engineer-core-ai-platforms-gusto-7892019 ## About the Role * Successful applicants typically have 8+ years of software development experience * Hands-on experience taking AI/LLM capabilities to production - agent orchestration, tool integration, retrieval, and evaluation/feedback loops that keep AI improving safely * AI fluency: fluent, daily use of AI coding assistants (e.g., Claude Code, or equivalent AI harness) across the development lifecycle - writing, reviewing, debugging, * and documenting code - with strong judgment on when to apply them, how to evaluate output quality, and how to stay current as the tooling evolves * Passion for creating scalable, efficient platforms for users * Curiosity and experimentation with emerging AI frameworks, applying and sharing best practices to evaluate and scale AI use safely across teams Others: * Experience in, or interest working in, Ruby on Rails * Appreciation for a collaborative, test-driven environment * Ability to build well-structured, maintainable, well-documented code * Ability to effectively communicate across engineering teams and with business stakeholders Do you prefer heavy feature development instead? Check out our Staff Software Engineer, Core Products job listing. Please note that a two day travel to a Gusto office for onboarding is required for this position. If you have any questions regarding this requirement, please share with your recruiter. ## Description We're looking for seasoned full-stack software engineers to join the teams behind Gusto's AI product platforms - the shared systems that our product teams build upon - to serve small business owners every day. As a Staff Software Engineer, you'll operate across the full lifecycle of foundational systems: deliver production AI agent systems - multi-agent orchestration, tool/workflow registries, agent-to-agent handoffs, human-in-the-loop escalation, and long-running conversation state, shaping architecture early in the design process, building self-service internal features and APIs, and owning their performance long after launch. That means engineering the core business engine, enabling product teams with reliable backend services, and setting the engineering standard for those around you. If you're drawn to work that combines technical craft with real-world impact - helping power the livelihoods of millions using Gusto products - join us! Here's what you'll do day-to-day: * Design and maintain evaluation frameworks across offline and online environments - including golden datasets, LLM-as-judge pipelines, and production replay - while establishing regression gates and end-to-end observability and tracing for agent runs * Design, build, and test Gusto core platform services - communications, reporting, dashboards, access, workflows, risk, payments, and compliance capabilities, among others * Mentor other engineers to help solve some of the hardest technical problems out there in very complex domains and at a large scale * Help scale one of the largest Ruby/Rails and Javascript/React applications in the world * Collaborate with our Product Engineering, Product Management, Data, and Design teams to understand customer pain points, come up with solutions, and then prototype, iterate, and launch daily * Build platforms that engineering teams rely on, and trust to deliver products that our customers genuinely love ## Related Videos - [Engineering Mindset in the Age of AI - Gunnar Grosch, AWS](https://www.wearedevelopers.com/videos/1735-engineering-mindset-in-the-age-of-ai-gunnar-grosch-aws) - [Coffee with Developers: David Heinemeier Hansson](https://www.wearedevelopers.com/videos/875-coffee-with-developers-david-heinemeier-hansson) - [Watch Tests Go Brrrr! : Getting Started with Cypress in ReactJS](https://www.wearedevelopers.com/videos/282-watch-tests-go-brrrr-getting-started-with-cypress-in-reactjs) - [Developing the Backend with Stefan Lingler, CTO at Shpock](https://www.wearedevelopers.com/videos/100360-developing-the-backend-with-stefan-lingler-cto-at-shpock) - [Coroutine explained yet again 60 years later](https://www.wearedevelopers.com/videos/690-coroutine-explained-yet-again-60-years-later) - [Nest.js - TypeScript in the backend can also be clean](https://www.wearedevelopers.com/videos/1033-nest-js-typescript-in-the-backend-can-also-be-clean) ## Related Articles - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [MLOps And AI Driven Development](https://www.wearedevelopers.com/magazine/82-mlops-and-ai-driven-development) - [What is Agentic Programming and Why Should Developers Care?](https://www.wearedevelopers.com/magazine/625-what-is-agentic-programming-and-why-should-developers-care) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Dev Digest 132 - Binging WADFlix?](https://www.wearedevelopers.com/magazine/473-dev-digest-132-binging-wadflix) - [Navigating the AI Shift](https://www.wearedevelopers.com/magazine/629-navigating-the-ai-shift)