zed-nextflow

Nextflow language support for Zed, powered by:

• The Nextflow language server (nextflow-io/language-server)
• Tree-sitter syntax parsing (nextflow-io/tree-sitter-nextflow)

This extension provides Nextflow file recognition, syntax highlighting/folding, bracket auto-closing, and LSP-backed editor features.

Features

• Language registration for *.nf files and Nextflow shebang scripts
• Syntax highlighting via Tree-sitter queries in languages/nextflow/highlights.scm
• Code folding via Tree-sitter queries in languages/nextflow/folds.scm
• Language server integration for completions and language intelligence
• Automatic language server download on first use:
  • Fetches the latest release from nextflow-io/language-server
  • Downloads language-server-all.jar
  • Starts it with java -jar ...

Requirements

• Zed
• java available in your PATH (required to run the Nextflow language server JAR)
• Rust toolchain (only needed if you want to build the extension locally)

Install / Run

As a local dev extension

1. Clone this repository.
2. Build the extension WebAssembly artifact:

cargo build --release --target wasm32-wasip2
cp target/wasm32-wasip2/release/my_zed_nextflow.wasm extension.wasm

3. In Zed, load this folder as a dev extension (Extensions UI).
4. Open a .nf file.

On first activation, the extension downloads language-server-all.jar and then launches it with Java.

Compatibility matrix

Component	Requirement	Notes
Zed	Recent stable release	Extension API dependency is zed_extension_api = 0.7.0
Java	java in PATH	Required to run language-server-all.jar
Rust (dev only)	Stable toolchain	Needed to build extension.wasm locally
Nextflow language server	Latest GitHub release	Downloaded automatically at first run
OS	Linux / macOS expected, Windows untested	Runtime command currently uses /bin/sh -c

Development

Useful commands

# Fast compile check for the extension crate
cargo check

# Build production wasm artifact used by Zed
cargo build --release --target wasm32-wasip2

# Copy build artifact to the extension root
cp target/wasm32-wasip2/release/my_zed_nextflow.wasm extension.wasm

Optional native helper binaries

The repository includes helper binaries under src/bin that are gated behind the native-helpers feature:

cargo run --features native-helpers --bin debug
cargo run --features native-helpers --bin real_donwloader

These binaries are for local debugging/downloading experiments and are not part of the wasm extension runtime.

Project layout

• extension.toml - Zed extension metadata and grammar/LSP wiring
• src/lib.rs - Main extension implementation (download + launch language server)
• languages/nextflow/config.toml - Language config (suffixes, brackets, comments)
• languages/nextflow/highlights.scm - Highlight query rules
• languages/nextflow/folds.scm - Folding query rules
• grammars/nextflow/ - Tree-sitter grammar source checkout

Notes

• The grammar revision is pinned in extension.toml.
• The language server JAR is downloaded from the latest GitHub release and stored in the extension's writable runtime directory.

Troubleshooting

java: command not found

• Install a JRE/JDK and ensure java is available in your shell PATH.
• Verify with:

java -version

Language server does not start

• Confirm network access to GitHub releases (nextflow-io/language-server) on first run.
• Rebuild and refresh the wasm artifact:

cargo build --release --target wasm32-wasip2
cp target/wasm32-wasip2/release/my_zed_nextflow.wasm extension.wasm

• Reload the extension in Zed and reopen a .nf file.

Syntax highlighting looks incomplete

• Confirm the grammar and query files are present:
  • languages/nextflow/config.toml
  • languages/nextflow/highlights.scm
  • languages/nextflow/folds.scm
• Rebuild extension.wasm, reload the extension, and reopen the file.

License

This project is licensed under the MIT License.

See LICENSE for details.

Publishing checklist

• Ensure extension.wasm is rebuilt from current sources.
• Validate extension metadata in extension.toml (id, version, repository, description).
• Smoke-test by opening a .nf file in a clean Zed profile and confirming LSP startup/completions.
• Add CI workflow(s) in .github/workflows/, then wire status badges in this README.