Hitaji Brain — Agent Platform & Sandboxed Code Runtime

Ongoing1 developer

A production agent platform with 97 authorized business capabilities and a sandbox where models can analyze live data without directly mutating it.

Technologies Used

NestJSTypeScriptQuickJS (WASM)PostgreSQLZodMCPLangSmith

The Challenge

Giving an LLM real tools against a real ERP is where most agent projects quietly break. Ninety-odd tools means ninety-odd places to forget a permission check. And the moment you let the model run code so it can read across several endpoints at once, you have handed it the ability to write too.

The Solution

I unified in-app and external-agent tools behind one capability registry and authorization boundary. For multi-step analysis, LLM-authored TypeScript runs in a QuickJS/WASM isolate with per-user read-only bindings, budgets, and deadlines. Writes are structurally unavailable inside the sandbox; proposed actions return to the user for confirmation.

Key Features

97 LLM-callable capabilities across ERP, HR, and task domains behind a single authorization path — agents inherit exactly the role checks the REST API enforces

Code mode: LLM-authored TypeScript executes in a QuickJS WASM isolate over read-only bindings, with a host-side read budget and wall-clock deadline

Writes are structurally impossible from inside the sandbox — the model returns a proposed action, and the backend turns it into a human confirmation card

Replaced the sandbox's async runtime after isolating a WASM corruption defect in multi-read workloads, then proposed fixes upstream (see Open-Source Contributions)

Pure WASM — no native addon, no Docker build tooling, runs the same in dev and prod

Retrieval over the product corpus with pgvector; LangSmith tracing end to end

Impact & Results

Live in production. Replacing the failing async runtime made multi-read code execution reliable while preserving a portable, pure-WASM deployment.

My Role: AI Engineer & Architect

Interested in working together?

Email me about a role or project