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Aside

engineering opportunity

MTS - Agent Harness

MTS - Agent Harness role at Aside in San Francisco, CA, US. Focus areas include TypeScript, Distributed Systems, Software Architecture, Evals, AI Agents, Accessibility. Build an agent that uses your computer. Build benchmarks and evaluation environments to test changes, catch regressions, and understand where the agent still fails on real tasks.

San Francisco, CA, USFull-time

Posted

About the role

What will you do at Aside?

About Aside

Aside is a personal work agent built as a browser. Since it works where your accounts and context already live, it can securely use your logins, passwords, and existing sessions to complete work on your behalf across the web. Its browser agent scores 99.0% on Mind2Web, 40% smarter than Claude Cowork with Opus 4.7.

Aside runs local-first, with memory and data protected on the user’s device. More than 50k people use Aside today, and we’re growing 25% week over week. The context Aside is a personal work agent that does your work for you.

We want to make the agent faster and more efficient while improving its ability to use a computer. These goals go hand in hand. We need an engineer who can dig into our agent harness, run experiments, and make it better.

You will: Polish our browser automation framework and memory system. You can make everything from the ground up, from the agent loop, compaction, memory to browser automation framework. Here’s an article how we did.

Build an agent that uses your computer. Help Aside navigate browsers and desktop apps, understand what’s on screen, and complete tasks across them. Optimize our harness.

Reduce token usage, work around bot detection, and experiment with heuristics that replace long prompt instructions with predictable behavior. Run real-world experiments. Build benchmarks and evaluation environments to test changes, catch regressions, and understand where the agent still fails on real tasks.

Build with users. Talk to them, understand where the agent falls short in their work, and turn their feedback into shipped improvements. What we’re looking for Use your brain.

No benchmaxxing or /autoresearch. You read the code and prompts yourself, make changes line by line, and understand why each change helps. An obsession with optimization.

You care about making the agent more capable while reducing latency and cost. You track down wasted tokens and unnecessary steps, and measure whether your changes help. Systems rigor.

You understand how Chrome DevTools Protocol, Playwright, and accessibility trees work, and know how to put them to use. Platform thinking. You think in primitives, not just features.

You build solutions that solve today’s product needs while supporting future use cases. Proactivity. You create your own tasks.

When something breaks or feels below the bar, you propose a solution and ship the improvement as if the product were your own. How we work We’re a small, talent-dense team. Everyone has broad ownership.

You'll work directly with the founders. You’ll directly talk to users through our community and interviews. Our office is based in San Francisco.

We can help on housing (we have co-living house) and visa (depends on the situation).

Which skills does this role require?

TypeScriptDistributed SystemsSoftware ArchitectureEvalsAI AgentsAccessibility

Make your next move

Build a shortlist and prepare

Identify the requirements you can demonstrate, then choose examples from your work to discuss with the hiring team.

Review the responsibilities and requirements before adding an opening to your shortlist.

Role information can change. Prepin can help you prepare, but does not submit an application for this role.

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