Nythrex

Service · LLM applications

LLM applications people actually keep using.

Building a chat window on top of a model takes an afternoon. Building an LLM product that people trust, that handles edge cases, that stays affordable at scale and that you can improve safely takes engineering. We build the whole thing: UX, backend, AI layer, integrations and operations.

ImprovesafelyReal usageFeedback & logsNew test casesChange prompt /modelRun evalsShip
The loop that keeps an LLM product improving without breaking what already works.

What we build

LLM UX: the part most teams skip

  • Show sources so users can verify instead of trusting blindly.
  • Stream responses and show progress for multi-step work — perceived speed matters.
  • Make correction easy: edit, regenerate, thumbs down with a reason. Every correction is future training data.
  • Design the “I don’t know” state as carefully as the happy path.
  • Set expectations in the interface: what the assistant can and can’t do.

Typical stack

Frontend

  • React / Next.js
  • React Native
  • Streaming UI
  • Feedback capture

AI layer

  • Model gateway
  • Prompt registry
  • RAG
  • Tool calling
  • Guardrails
  • Evals in CI

Backend

  • .NET
  • Node.js
  • Python
  • Queues
  • Auth & permissions

Cloud & ops

  • Azure / AWS / GCP
  • Terraform
  • Observability
  • Cost dashboards

Frequently asked questions

Want a second opinion on your project?

Tell us what you’re building and where you’re stuck. We’ll reply within one business day with the most practical next step — even if that step isn’t us.

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