codelibs/fess

Open-source, self-hosted enterprise & site search server built on OpenSearch. Crawls web / file / DB / cloud sources, 20+ languages, REST API, and AI/RAG & semantic search. Apache-2.0.

What it solves

Fess provides a centralized, enterprise-grade search server that allows organizations to index and search across fragmented data sources. It eliminates the need for users to know where a document is stored by providing a single search interface for web sites, file systems, and various third-party data stores.

How it works

Fess is built on top of OpenSearch. It uses a built-in crawler to collect documents from a wide range of sources—including web pages, local file systems, databases, and SaaS platforms like Slack or SharePoint—and indexes them for full-text search. The system is managed via a browser-based administration UI, removing the requirement for direct OpenSearch configuration knowledge.

Who it’s for

It is designed for enterprises and organizations that need a private, self-hosted search engine to index internal documents, corporate intranets, and cloud storage.

Highlights

Broad Data Integration: Supports crawling from S3, Git, Salesforce, Office 365, Confluence, Jira, and more.
Enterprise Security: Includes role- and permission-based filtering of search results and SSO integration with LDAP, SAML, and Microsoft Entra ID.
Flexible Indexing: Supports numerous file formats including PDF, Microsoft Office, and ZIP archives.
Extensible Architecture: Can be customized via data store, ingest, script, and theme plugins.