Integration: Open WebUI

Use Open WebUI as a chat frontend for your Haystack apps through Hayhooks

Authors

deepset

Table of Contents

• Overview
• Installation
• Usage
• License

Overview

Open WebUI is an open-source chat UI for LLM apps. By exposing your Haystack pipelines and agents through Hayhooks as OpenAI-compatible endpoints, you can use Open WebUI as the frontend: run Hayhooks and Open WebUI (separately or via Docker Compose), then connect Open WebUI to Hayhooks in Settings. You get streaming, optional status and notification events, and optional OpenAPI tool server integration.

For full details, see the Hayhooks Open WebUI integration guide.

Installation

Install Hayhooks:

pip install hayhooks

Install and run Open WebUI separately, e.g. with Docker:

docker run -d -p 3000:8080 --add-host=host.docker.internal:host-gateway -e WEBUI_AUTH=False -v open-webui:/app/backend/data --name open-webui ghcr.io/open-webui/open-webui:main

For a pre-wired setup, use the Hayhooks + Open WebUI Docker Compose (see Quick Start with Docker Compose).

Usage

Connect Open WebUI to Hayhooks

1. Start Hayhooks with your pipelines:

   hayhooks run --pipelines-dir ./pipelines
   

2. In Open WebUI go to Settings → Connections and add a connection:

   • API Base URL: http://localhost:1416 (or http://hayhooks:1416/v1 when using Docker Compose)
   • API Key: any value (Hayhooks does not require auth)

3. In a new chat, select your deployed pipeline as the model.

Pipeline wrappers must support chat completion (e.g. implement run_chat_completion or run_chat_completion_async). See OpenAI compatibility and the pipeline examples for implementation details.

Optional: Open WebUI events

For status updates, notifications, and tool-call feedback in the UI, use helpers from hayhooks.open_webui in your pipeline and stream OpenWebUIEvent objects. See Open WebUI Events and the open_webui_agent_events and open_webui_agent_on_tool_calls examples.

License

hayhooks is distributed under the terms of the Apache-2.0 license. Open WebUI is subject to its own license.