zed-nextflow

Nextflow language support for Zed, built on the Nextflow tree-sitter grammar and the Nextflow language server.

Features

• Syntax highlighting for .nf scripts and .config files
• Bash highlighting inside script and stub blocks
• Diagnostics, go-to-definition, completion, hover, and formatting from the language server
• Outline view for processes, workflows, and functions
• Automatic download of the language server JAR, pinned to a Nextflow version

Requirements

Java 17 or later, to run the language server.

Install

Open the command palette, run zed: extensions, search for Nextflow, and install.

Open a .nf file to start the language server. It downloads its JAR on first use, so the first open takes a moment and needs network access.

Configuration

Settings go under the lsp key in your global Zed settings.json, or in a project's .zed/settings.json.

{
  "lsp": {
    "nextflow-language-server": {
      "settings": {
        "nextflow": {
          "languageVersion": "26.04",
          "java": {
            "home": "/path/to/jdk-17-or-later"
          },
          "languageServer": {
            "path": "/absolute/path/to/language-server-all.jar"
          },
          "errorReportingMode": "warnings",
          "files": {
            "exclude": [".git", ".lineage", ".nf-test", ".pixi", ".venv", "work"]
          }
        }
      }
    }
  }
}

The extension sends the same language server defaults as the VS Code extension:

Setting	Default
nextflow.completion.extended	false
nextflow.completion.maxItems	100
nextflow.debug	false
nextflow.errorReportingMode	"warnings"
nextflow.files.exclude	.git, .lineage, .nf-test, .pixi, .venv, work
nextflow.formatting.harshilAlignment	false
nextflow.formatting.maheshForm	false
nextflow.formatting.sortDeclarations	false

Anything you set in settings.json overrides these. See Configuring language servers.

Two settings are extension-specific rather than language server settings:

• nextflow.java.home points at a JDK. Without it the extension looks at JAVA_HOME, then PATH.
• nextflow.languageServer.path points at a JAR you built yourself, which skips the download. Useful when working on the language server.

nextflow.languageVersion picks which language server release to download. Supported values are 26.04 (the default), 25.10, 25.04, and 24.10. The extension downloads the newest patch release for that version. Restart the language server after changing the version, the JDK, or the JAR path.

Development

Clone the repository, then run zed: install dev extension from the command palette and pick the directory. Zed builds and installs it, replacing the registry version until you uninstall it. This needs Rust.

cargo build --release --target wasm32-wasip2

Query files live in languages/nextflow/. After editing one, run zed: reload extensions to see the change. To check a query against the grammar:

tree-sitter query languages/nextflow/highlights.scm path/to/script.nf

The grammar revision is pinned in extension.toml. Bump it when tree-sitter-nextflow cuts a release, and re-run the queries against the new revision, since node names can change.

To publish a new version, bump version in extension.toml and Cargo.toml, then open a PR against zed-industries/extensions updating the version for nextflow in extensions.toml.

Credits

This extension is built on several community contributions:

• ctuni/zed-nextflow
• DLBPointon/zed_nextflow
• Sam-Sims/nextflow-zed
• valentinegb/zed-groovy