OpenFastTrace Language Server

What is OpenFastTrace Language Server?

OpenFastTrace (short OFT) is a requirement tracing suite. It keeps track of whether you actually implemented everything you planned to in your specifications.

The OpenFastTrace Language Server brings OFT support into code editors through the Language Server Protocol (LSP). One server process understands OFT specification items and coverage tags. Any LSP-capable editor can connect to it. This repository ships two clients that do exactly that: an IntelliJ IDEA plugin and a VS Code extension.

You can learn more about requirement tracing and the OFT format in the OFT user guide.

Quickstart

The easiest way to get started with the OpenFastTrace Language Server is to install a pre-built client from the releases.

IntelliJ IDEA

1. Download the latest plugin ZIP from the Releases page.
2. Open IntelliJ IDEA Ultimate.
3. Go to Settings → Plugins.
4. Click the gear icon and select Install Plugin from Disk.
5. Select the downloaded ZIP file.
6. Restart IntelliJ IDEA when prompted.

VS Code

1. Download the latest .vsix from the Releases page.
2. Run code --install-extension <downloaded-file>.vsix, or open the Extensions view, click the ... menu and choose Install from VSIX....

Both clients start the OpenFastTrace Language Server automatically when a supported file is opened. No additional configuration is required.

For building a client yourself or running the language server standalone, see the development instructions below.

Project Information

• Bachelor thesis project, work in progress
• Java 17, LSP4J 1.0.0 (LSP 3.18), OFT 4.8.0
• License: GPL-3.0-or-later
• Requirements: doc/spec/, architecture decisions: doc/decisions/

Using the Language Server

The server provides these features to any connected editor:

• Hover documentation. Hovering over a coverage tag shows the referenced specification item's title and description.
• Go to Definition. A coverage tag jumps to the specification item in Markdown. A specification item ID jumps to all its covering tags.
• Find References. Lists every coverage tag in the workspace that covers a specification item.
• Diagnostics with quick fix. Coverage tags that reference an outdated revision get a warning. The quick fix updates the version number to the current revision.
• Syntax highlighting. Specification item definitions, section keywords and coverage tags are reported as semantic tokens.
• Code completion. Specification item IDs are suggested while typing a Covers: entry or a coverage tag target such as [impl->.
• Symbol search. Specification items are found through the editor's workspace symbol search.
• Rename. Renaming a specification item updates its definition together with every coverage tag and Covers: entry in the workspace.
• Tag skeletons. Invoking completion manually in comments offers [impl->...], [utest->...], [itest->...] and [stest->...].

Getting the Project

git clone https://github.com/fgorke/openfasttrace-language-server.git

Installation

Runtime Dependencies

• Java 17 or later
• For the IntelliJ plugin: IntelliJ IDEA Ultimate 2026.1 or later.
• For the VS Code extension: VS Code 1.82 or later

Build Dependencies

• Maven 3.6 or later for the server
• Gradle is bundled as a wrapper in intellij-plugin/
• Node.js and npm for the VS Code extension in vscode-extension/

Building

Build the server and run all tests:

mvn verify

The build produces a standalone fat JAR at target/openfasttrace-language-server-*-standalone.jar.

Running

Standalone

java -jar target/openfasttrace-language-server-*-standalone.jar

The server speaks LSP over stdio. Any editor with an LSP client can launch it this way.

IntelliJ IDEA Plugin (Development)

The intellij-plugin/ module wraps the server for IntelliJ IDEA Ultimate.

Run a sandbox IDE with the plugin during development:

mvn package
cd intellij-plugin
./gradlew runIde

Build an installable plugin ZIP:

mvn package
cd intellij-plugin
./gradlew buildPlugin

The ZIP lands in intellij-plugin/build/distributions/.

VS Code Extension (Development)

The vscode-extension/ module wraps the server for VS Code.

Run an Extension Development Host during development:

mvn package
cd vscode-extension
npm install
npm run watch

Then press F5 in VS Code (with vscode-extension/ open as the workspace) to launch it.

Build an installable package:

mvn package
cd vscode-extension
npm install
npx vsce package

The .vsix lands in vscode-extension/.

Requirement Tracing

This project traces its own requirements with OpenFastTrace. Features live in doc/spec/features.md, requirements in doc/spec/requirements.md. The testing approach is documented in ADR-0009.

Related Projects

• OpenFastTrace: the requirement tracing suite this server builds on
• OpenFastTrace IntelliJ Plugin: the native PSI-based IntelliJ integration by the itsallcode team
• LSP4J: the Java implementation of the Language Server Protocol used here

Development

Tests follow a Given-When-Then structure and are split into unit and integration tests. See ADR-0009 for the full testing strategy.

mvn test

License

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

See LICENSE for the full text. OpenFastTrace is licensed under GPL-3.0-or-later. This project links OFT on the classpath, so it is GPL-3.0-or-later as well (see ADR-0005).