Harper

Staff Engineer, Harness Engineering

San Francisco · Staff+ · Part-time

Sponsorship not specified$253k-$308kDetected 50 days ago

LogisticsCommunication

About the role

The companies that win with agents don't win because they found one magic model.
You define the contracts every Harper agent integrates against - the meta-harness wrapping our coding agents and the model-routing layer over our foundation-model providers.
Do this right and every new agent ships faster, fails smaller, and learns from the systems that came before it.

open-source agent/harness contributions; sandbox/isolation depth; foundation-model partner or early-access experience.
You own the layer every other agent team builds against, so the leverage is enormous and so is the scrutiny - a harness decision you make shows up in every pod's velocity.

The agent loop - prompt construction, tool routing, context-window management, retry/timeout/budget logic, multi-step orchestration.
The tool layer - the canonical set of tools every agent can call. Schema, auth, rate-limit, observability per tool.
Model-provider abstraction - provider routing, fallback chains, cost/latency tradeoffs, eval-driven model selection.
Guardrails - banned tool combinations, prompt-injection defense, data-egress policy, PII scrubbing.

$253,000-$308,000 cash (base + target performance bonus), plus competitive equity.

Uber commuter benefits; breakfast, lunch, and dinner provided; snacks and coffee stocked; free gym membership; health, dental, and vision.

Harper is an AI-native commercial insurance company, based in San Francisco and built from scratch.
Most knowledge work is judgment locked inside people's heads - the exceptions, the precedents, the decision traces no one ever wrote down.
Converting that judgment into software is one of the largest human-to-computational transitions still in front of us, and we think the most honest place to prove it is the hardest one: commercial insurance, a trillion-dollar industry that is still, even now, more than 90% done by hand.
We're not patching legacy workflows or adding a copilot to them.
We're rebuilding the business so that AI does the work and people do the judgment that AI can't yet - and then teaching it that, too.
~1,000 new customers a month and roughly 100x growth in the past year.
That pace sets the culture.
We're on-site in San Francisco, in the building together, working long days to high standards - because a rebuild this large doesn't happen part-time or by committee.
Almost no one joins Harper because they're passionate about insurance.
They join because they want to be on the frontier of the AI transition, doing the most consequential work of their career, in a company being built to define a category rather than join one.
If that's the work you're looking for, insurance is just where you get to do it.

This listing is sourced directly from Harper's careers page and normalized into a canonical job model.