Thinking about
what we build

On AI engineering, physics simulation, and building software at scale.

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Essay

Learning Auto-Routing by Building: From Brute Force to an Auto-Design Agent

How I learned auto-routing for photonic chips — a failed brute-force attempt, AI as a learning partner, interactive HTML arenas, a PhotonForge router, and an agent that iterates 27 designs in under three minutes.

Prash Kharel
Case Study

Predicting Peak Memory for an Electromagnetic Mode Solver

How we replaced a heuristic memory estimate with a calibrated model for Tidy3D mode solver workloads, eliminating under-predictions across the calibration set.

Momchil Minkov
Essay

Can AI Agents Autonomously Design Components on Photonic Chips?

We gave AI agents a photonic simulator, a DRC engine, and four design challenges. They autonomously designed waveguide bends, crossings, splitters, and demultiplexers — some reaching near-perfect performance.

Tyler Hughes
Tutorial

Designing a Photonic Chip Component with ~45 Lines of Python

A compact introduction to photonic inverse design with Tidy3D, using a pre-built simulation and a ~45-line optimization loop.

Tyler Hughes
Case Study AI Engineering

"What Should We Work On Next?"

The story of building an 80,000-line autodiff library almost entirely through AI agents — and the verification infrastructure that made it possible.

Yannick Augenstein & Frederik Schubert
Essay AI Engineering

The Agent Control Loop — Engineering for Tolerance

Why agent reliability isn't magic model behavior — it's an environment where correctness is continuously verified. A framework for deciding when and how to delegate to AI agents.

Frederik Schubert & Yannick Augenstein