Sr Software Engineer - Coding Agents

About this role

Lexsi Labs is the leading frontier AI lab focused on building aligned, interpretable, and safe superintelligent systems. While that is the vision, the mission to build safety aware autonomous system in the extreme near term. Our research work spans around areas like AI alignment methodologies, interpretability led system design, and foundational model research across structured, tabular, and new autonomous system designs. We published about 25+ papers in the past 15 months across leading conferences ICLR, ICML, WWW, IJCNN, MICCAI, Eurips etc. Our labs are located in India (Mumbai & remote), Paris, & London.

We operate with a flat structure, high autonomy, and a strong bias toward engineers who take full ownership of what they build, from architecture to production behavior.

The Role

Our current sprint on building autonomous system for complex problems, across software engineering, data science, and AI research involves building harness, execution substrate and evaluation system, and each is designed to run inside a customer's environment rather than ours.

This role owns the coding agent: a system that takes an objective, works directly on a repository, verifies its own changes, and produces a record of what it did. The codebases are large, old, thinly tested and load-bearing, and the agent runs inside the customer's network, usually without internet egress.

What'll you work on:

• The agent architecture and its tool surface for software work, including retrieval, editing, builds, tests, static analysis and version control.
• Verification, so that a change is established as correct before a human sees it.
• Long-horizon execution across multi-file refactors and migrations, with checkpointing, recovery and self-correction.
• The authorisation and rollback model governing what the agent may do and how it is undone.
• Integrations with the engineering estate the agent operates in, and the observability tooling used to debug and audit it.
• Evaluation su...