# Build brief — a focused alternative to Admix

> **Verdict:** Partly, if you narrow it · **Buildability:** 63/100 · **Category:** AI Assistant
> **Source:** https://www.canitbevibecoded.com/admix
> Independent editorial assessment from Can It Be Vibe Coded? Not affiliated with, endorsed by, or derived from Admix. Verify current pricing and capabilities before acting.

## Context

**Admix** — Multi-model AI chat that compares answers side by side across providers. It currently costs $10/mo.

A local chat UI with side-by-side replies is a contained project when it calls OpenRouter, but Admix's value depends on access to many hosted models, a current catalog, provider routing, and a maintained account and billing layer. You can reproduce the comparison workflow. You cannot reproduce the model access and service layer for a flat $10 subscription.

This brief describes a focused, single-operator replacement for the part of Admix that is genuinely reproducible. It is deliberately narrower than the product it replaces, and it says so in writing. Build the useful core; do not pretend to have rebuilt the rest.

## What you are building

Send one prompt to selected models through OpenRouter, stream the replies into a side-by-side grid, and save the thread locally.

- Build a focused single-user workflow with real persistence, search, and export.
- A responsive interface with real empty, loading, success, and error states.

## Requirements

### Functional

- Node 22.
- SQLite.
- Provider and model IDs to compare.

### Data and integrations

- OpenRouter API key in.env.

Each of these needs a real account, credential, or quota. Set them up before writing feature code.

### Non-functional

- Accessibility: semantic markup, labelled controls, visible focus, and reduced-motion support.
- Security: server-side secrets, validated input, and no credentials in the client bundle.
- Reliability: retries with backoff on external calls, and a clear failure state when a provider is down.
- Portability: the operator can export their data and leave without losing it.

## Implementation brief

Build me a local multi-model comparison chat to replace Admix. Requirements:

- Node 22 + Express + better-sqlite3, a server-rendered shell with a little vanilla
  JS for streaming; no frontend framework, no build step.
- One OpenRouter key in .env, kept server-side; the server proxies all model calls.
- A model picker fed from OpenRouter's /models endpoint; select up to four models.
- One prompt fans out to the selected models and streams each reply into a
  side-by-side grid with model name, elapsed time, and token usage when reported;
  a failed model shows its error in its own column without killing the others.
- Markdown rendering with fenced code blocks and a copy button per reply.
- Threads, prompts, model ids, replies, and timestamps in SQLite; full-text search
  across saved threads; export a thread as Markdown.
- A running cost estimate per thread from OpenRouter's usage and pricing fields.
- Binds to localhost only. No accounts, no telemetry; prompts and replies leave the
  machine only for OpenRouter, and the README says so.
- Out of scope: auth, billing, mobile apps, image generation, hosted sync, and
  provider-specific tools like web search or file upload.
- README: setup, .env.example, and how to add a model id by hand if the catalog
  fetch fails.

## Delivery standard

- Inspect the repository first, then write a short implementation plan before writing code.
- Deliver the smallest complete end-to-end workflow first; every primary control must work against persisted data.
- Use real validation and storage; never substitute fake dashboards, decorative controls, hard-coded success states, or mock integrations.
- Include responsive layouts plus genuine empty, loading, success, validation, and failure states.
- Keep secrets server-side in environment variables, provide .env.example, and never commit credentials or user data.
- Add structured logs around every external call and return actionable errors without leaking sensitive details.
- Write unit tests for the core logic and one automated test of the main user journey.
- Finish with a README covering setup, architecture, data location, backups, tests, deployment, and known limitations.

## Acceptance criteria

- [ ] A clean install starts the app using only the README and .env.example.
- [ ] The primary journey works from first visit through saved result, reload, edit, export, and deletion where applicable.
- [ ] Invalid input, missing configuration, provider failure, and an empty database each have a usable state.
- [ ] The interface works at 390px and 1440px, is keyboard navigable, and shows visible focus on every control.
- [ ] Tests, type checking, linting, and a production build all pass with no ignored failures.
- [ ] No part of the interface implies a live integration, security guarantee, or scale capability that was not actually built and verified.

## Non-goals

Do not build these, and do not claim to have replaced them:

- Admix's bundled access to many providers under one subscription.
- A maintained model catalog and provider routing.
- Cross-device sync and account history.
- Built-in image, search, and document workflows.
- Connectors, OAuth flows, and vendor API changes require constant upkeep.
- The last 20 percent is sync, migration fidelity, speed, and edge cases.

## What you still own after launch

- Secure credentials, rotate secrets, and handle provider rate limits.
- Run migrations, backups, restores, and dependency updates.
- Test the critical journey after every model, API, or hosting change.
- Monitor failures and fix the edge cases a first prompt will miss.
- Maintain every third-party integration as APIs and OAuth rules change.

## Risk

**Operational risk.** The code is achievable; dependable data, integrations, and ongoing operations are the real cost.

Editorial confidence in this assessment: high. No independent one-shot implementation is linked yet.

## Prior art

Working open-source software you can read, fork, or borrow from before starting:

- [Open WebUI](https://github.com/open-webui/open-webui) — Open-source self-hosted chat interface for local and hosted models
- [LibreChat](https://github.com/danny-avila/LibreChat) — Open-source multi-model AI chat platform for self-hosting API-based assistants

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Generated by [Can It Be Vibe Coded?](https://www.canitbevibecoded.com) · Full report: https://www.canitbevibecoded.com/admix