Member of Technical Staff (Evals & Post-Training)

What we do

Ambral Labs helps enterprises own the intelligence behind their most important workflows.

Every company has years of historical evidence showing how work gets done: the context people had, the decisions they made, the actions they took, and the outcomes that followed. Today, most of that history is inert. It isn’t structured in a way that companies can use to evaluate models and improve agent behavior.

Ambral turns this history into replayable environments and eval sets grounded in real workflows and observed outcomes. We use those environments to improve model performance through reinforcement learning and other post-training techniques, alongside context engineering, harness design, and agent engineering.

The result is better, more cost-efficient AI for each enterprise’s specific work, powered by open-weight models that the company owns and controls. This allows each company to retain ownership of its core intelligence instead of outsourcing it to a model provider.

We graduated from YC S2025, raised millions in funding, and are already deployed within multi-billion dollar enterprises. Now we're growing the founding team

What you’ll do

At the center of Ambral Labs is a replayable environment engine for the enterpirse.

The system reconstructs a company’s world as it existed at a particular moment in the past then exposes that state through the same tools an agent would use in production. This lets us place new policies and agent configurations inside real historical environments, observe how they reason and act, and grade their performance against real outcomes.

You'll work across research, infrastructure, and production systems including:

• Building an environment factory that converts recorded enterprise data and task definitions into runnable environments

• Designing graders that turn ambiguous business objectives into verifiable rewards