harnessrouter tech stack

harnessrouter is harnessRouter Community Edition: the self-hosted, Apache-2.0 edition of the unif. It runs on FastAPI, Next.js, React and 0 more, read from its public repo HarnessRouter/harnessrouter.

HarnessRouter Community Edition: the self-hosted, Apache-2.0 edition of the unified interface for agent harnesses. Run Codex, Claude Code, Hermes, PI, DSH, and more through one API, with sessions, streaming, files, cancellation, and failure handling. Implements the Unified Harness Protocol (UHP), an open standard. Your keys, your infrastructure. The stack shown is detected from the public repository edition; hosted infrastructure and optional services may differ.

Developer tools · web · https://harnessrouter.ai/ · 3,720 GitHub stars, Apache-2.0 (2026-10-27)

Built with

Backend

FastAPI (gateway/requirements.txt@edca78bffa40: fastapi)

Frontend

Next.js (ui/package.json@edca78bffa40: "next")
React (ui/package.json@edca78bffa40: "react")

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harnessrouter tech stack

Built with

Backend

Frontend

What do I use to build this?And how much will it cost?What do you want to build?

What Are You Building?

Prices read from each vendor’s own pricing page

One placefor every stack decision.

Plan

Cost as you grow

Vendors

Audit

Billing

Showcase

Give your AI assistantaccess to Kong Reviews.

See what real productsare built on.

How services are ranked

See what startups build on.

Already built?Start from what you run.

Pick what works.Build what’s next.

Audit Your Stack

What's it built on?

What it runs on

What matters

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My Stacks

Billing

Vendors

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Showcase

Built Something?

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Free

Paid Plans

Missing a Vendor?

Questions

Pick what works.Build what’s next.

What do I use to build this?
And how much will it cost?What do you want to build?

One place
for every stack decision.

Give your AI assistant
access to Kong Reviews.

See what real products
are built on.

Already built?
Start from what you run.

Pick what works.
Build what’s next.

Pick what works.
Build what’s next.