Jelu

Jelu is a self‑hosted, single‑file database application that functions as a personal “Goodreads” replacement. Built on Spring Boot, it exposes a RESTful API and a modern React front‑end that can be consumed by third‑party services or embedded in blogs via generated snippets. The core goal is to give developers full control over reading data while keeping the deployment footprint minimal.

Technical Stack

• Language & Framework: Java 17 + Spring Boot (fat JAR) for the back‑end; React/TypeScript for the UI.
• Database: SQLite (single file) – ideal for local, low‑traffic use cases and easy backups.
• API: REST + OpenAPI spec; authentication via JWT, LDAP, or reverse‑proxy headers.
• Build & CI: GitHub Actions with Docker image publishing to Docker Hub (wabayang/jelu).
• Internationalization: Crowdin‑driven translations, locale‑aware formatting.

Core Capabilities

• Metadata Import: ISBN, Google Books, Amazon, Goodreads, LibraryThing; also EPUB/OPF extraction.
• Author Management: Auto‑fetch Wikipedia bios, merge duplicates.
• Tagging & Shelves: Tags serve as dynamic filters; custom shelves are tag‑based.
• History & Statistics: Year/month views, reading speed metrics, export to CSV.
• User Management: Multi‑user with LDAP or reverse‑proxy support; per‑user libraries.
• Embedding: Generates embeddable HTML snippets for external sites or Markdown notes.
• Webhooks/Extensibility: HTTP callbacks on book state changes; plug‑in architecture for custom metadata providers.

Deployment & Infrastructure

Jelu ships as a Spring fat JAR or as a pre‑built Docker image, making it trivial to run on any Linux host with Java 17 or via container orchestration. The single‑file SQLite database can be mounted on persistent storage; the application scales vertically by adding CPU/memory, while horizontal scaling is limited to read‑only replicas due to SQLite’s file‑based nature. For higher concurrency, developers can replace SQLite with PostgreSQL and tweak the JPA configuration.

Integration & Extensibility

The exposed REST API allows developers to build dashboards, integrate with home‑automation systems (e.g., Home Assistant), or sync with external book trackers. Custom metadata providers can be added by extending the MetadataProvider interface, and webhooks enable real‑time updates in third‑party services. The application’s modular design lets contributors fork and add new features without touching the core.

Developer Experience

Documentation is hosted at https://bayang.github.io/jelu-web/, covering configuration, API usage, and deployment. The community is active on Discord and Matrix channels, providing rapid support. Licensing under MIT ensures freedom to modify and redistribute the codebase. The project’s CI pipeline guarantees that every release is thoroughly tested, which reduces integration friction for developers.

Use Cases

• Personal Knowledge Base: Embed reading logs in a personal website or Obsidian vault.
• Team Reading Clubs: Multiple users share libraries, review books, and generate collective statistics.
• Research Projects: Import EPUBs to extract metadata for academic bibliographies.
• IoT Integration: Use the camera ISBN scanner on a Raspberry Pi to log books scanned in a library kiosk.

Advantages

Developers favor Jelu for its lightweight, self‑contained architecture, complete data ownership via a single SQLite file, and robust API. Unlike commercial services that lock users into proprietary formats, Jelu’s open source nature allows full customization and on‑premises deployment. Its combination of modern Java back‑end, React UI, and extensive metadata sourcing makes it a compelling choice for anyone needing a reliable, extensible book‑tracking platform.