VS Code plugin for F# development


Ionide-VSCode: FSharp

Enhanced F# Language Features for Visual Studio Code

Part of the Ionide plugin suite. Read detailed documentation at Ionide docs page.

Version Installs Join the chat at https://gitter.im/ionide/ionide-project


  • F# (Windows) - Easiest way to install latest versions of F# on Windows is using VS Build Tools 2017. If you use VS 2017, make sure that you've installed workload adding F# support.

  • F# (Linux/MacOS) - F# on non-Windows platform is distributed as part of the mono. Installation guide and recent version of mono can be found on the project webpage and on the F# Software Foundation "Use on Linux" page

  • .Net Core SDK - .Net Core is modern, cross platform implementation of .Net Framework. Ionide is requiring it for set of features such as project modifications or debugging. The core part of SDK is dotnet CLI tool that provides easy way to create, build and run F# projects. What's important - the dotnet tool can be used also to create applications targeting also Full Framewok (like net461). For detailed instructions on installing .Net Core visit official step-by-step installation guide

  • VSCode C# plugin (optional) - Ionide's debugging capabilities relies on the debugger provided by Omnisharp team. To get it install C# extension from VSCode marketplace

  • MsBuild 2015 (Windows only, optional) - For old, verbose .fsproj files on Windows MsBuild 2015 (14.0) needs to be additionally installed. You can download it here. However, we highly recommend using new, SDK-based project files.


  • Syntax highlighting
  • Auto completions
  • Error highlighting, error list, and quick fixes based on errors
  • Tooltips
  • Method parameter hints
  • Go to Definition
  • Peak Definition
  • Find all references
  • Highlighting usages
  • Rename
  • Show symbols in file
  • Find symbol in workspace
  • Show signature in status bar
  • Show signature as CodeLens / LineLens
  • Go to MSDN help
  • Add open NAMESPACE for symbol
  • Match case generator
  • Go to #load reference
  • Generate comment for the symbol
  • Integration with F# Interactive
  • Integration with Forge (Project scaffolding and modification)
  • Integration with FSharpLint (additional hints and quick fixes)
  • Integration with MsBuild (Build, Rebuild, Clean project)
  • Solution / project explorer

How to get logs for debugging / issue reporting

  1. Enable Logging in User settings with
// FSharp configuration
  // Set the verbosity for F# Language Service Output Channel
  "FSharp.logLanguageServiceRequestsOutputWindowLevel": "DEBUG",

  // Enable logging language service requests (FSAC)  to an output channel, the developer tools console, or both
  "FSharp.logLanguageServiceRequests": "both"
  1. Open the Output Panel and switch to the F# Language Service Channel
  2. Or Toggle Developer Tools (Help |> Toggle Developer Tools) and open the console tab

How to contribute

Imposter syndrome disclaimer: I want your help. No really, I do.

There might be a little voice inside that tells you you're not ready; that you need to do one more tutorial, or learn another framework, or write a few more blog posts before you can help me with this project.

I assure you, that's not the case.

This project has some clear Contribution Guidelines and expectations that you can read here.

The contribution guidelines outline the process that you'll need to follow to get a patch merged. By making expectations and process explicit, I hope it will make it easier for you to contribute.

And you don't just have to write code. You can help out by writing documentation, tests, or even by giving feedback about this work. (And yes, that includes giving feedback about the contribution guidelines.)

Thank you for contributing!

Contributing and copyright

The project is hosted on GitHub where you can report issues, fork the project and submit pull requests.

The library is available under MIT license, which allows modification and redistribution for both commercial and non-commercial purposes.



Ionide couldn't be created without support of Lambda Factory. If you'd be interested in rich F# test integration check out our VSCode plugin - Neptune.

If your company would be interested in supporting development of Ionide, or acquiring commercial support sent us email - lambda_factory@outlook.com