PetaSight is a small company with a wide brief: a portfolio of products and proofs of concept, with a special emphasis on medtech. I came in as the founding engineer right after it acquired Babbage Insight, where I had been working, and the first job was the ground under everything else — multi-account AWS on Terraform and OpenTofu across the product verticals, a zero-trust, least-privilege IAM model, key rotation through Secrets Manager. ECS Fargate for compute, RDS for data, one VPC per account.
The first app we took all the way to a product is MyT+, an AI mental-wellness companion built on custom fine-tuned Bedrock models. I worked on it end to end: the backend and the agents behind it, the cross-platform build with Capacitor, App Store review, and the encryption — multi-party end-to-end, X25519 and AES-256-GCM, with keys generated in the browser so a conversation between a person and the model is unreadable to anyone else, including us. Alongside the app I helped build a robust training pipeline: PyTorch and PEFT fine-tuning LoRA adapters that deploy straight into Bedrock, and a streamlined loop for shaping the agents' tone and techniques.
The other products are earlier in their lives, and on those I work directly with the clients — understanding what they actually need, building the proof of concept, and turning the ones that land into something that ships. Under most of them sits the same foundation: an agent harness on Mastra with context-window management, memory and tool calling, and a Model Context Protocol server of about forty tools with OAuth 2.1 PKCE and dynamic client registration, so the products can be driven straight from Claude, Cursor and VS Code.
The piece I'm proudest of came out of a review problem. I was building a custom PR-review agent, and every product here is a multi-repo setup — a change in one repo can quietly break app integrity in another, which the usual review tools never see, because they assume one consolidated repo. So I built an internal graph knowledge base that maps the code across repositories, and the review agent reasons over that graph rather than over a single diff. On the same questions, same repos and same model, the graph roughly tripled what the agent got right — from almost nothing asserted correctly to about 80% — with zero hallucinations, for a small bump in cost.
What I'm building now is quoting software: a request to quote currently takes around 48 hours to turn around, and the goal is 30 minutes.
And the plumbing that keeps all of it honest: a CI/CD pipeline for the company's infrastructure on GitHub Actions with OIDC and AWS CodeBuild, with testing gates before anything reaches production.