GAEB4Linux – An Open Source GAEB XML Viewer Built with Spring Boot and Vaadin

Hi HN, I’m building GAEB4Linux, an open-source GAEB XML viewer for Linux. GAEB (Gemeinsamer Ausschuss Elektronik im Bauwesen) is a German standard used in construction for exchanging bills of quantities (BoQ), pricing, tenders, invoices, etc. Most existing tools are Windows-only and closed source. What it currently does Loads GAEB XML files (DA80 / DA81, e.g. X81) Parses via JAXB (generated from official XSD 3.3) Extracts BoQ structure and positions Displays: Position number (OZ) Short / long text Quantity Unit Unit price Total Clean multi-module architecture (Java 21, Spring Boot, Vaadin) Architecture The project is structured as: gaebviewer – Spring Boot app (UI + application logic) gaeb-schema-da80 – JAXB classes from DA80 XSD gaeb-schema-da81 – JAXB classes from DA81 XSD We’re moving toward a two-layer model: A complete, lossless GAEB tree model (all XML tags preserved) A domain projection model (BoQ, positions, prices) used by modules like viewer, calculation, export The idea is to make this a foundation for: Viewer Calculation module Cost breakdown analysis Potential export back to GAEB Later: project management + database Why? There’s no solid open-source GAEB tool for Linux. Construction IT is still heavily Windows-bound and proprietary. I’m interested in feedback on: Architecture decisions (Tree model vs. direct JAXB mapping) Handling large GAEB files efficiently Multi-format support strategy (DA80/81/83) Long-term maintainability Repo: https://gaeb4linux.de Happy to answer technical questions.