About msbuild-server
msbuild-server is a skill for developers running repeated .NET CLI builds. It enables the MSBuild Server to cache evaluation results and outlines sequential-build checks and server shutdown for troubleshooting.
Key features
- 01Enable the MSBuild Server
- 02Set the environment variable by shell
- 03Compare consecutive build times
- 04Shut down the server for troubleshooting
Use cases
- 01Speed up repeated incremental CLI builds
- 02Run many sequential builds in CI
- 03Investigate build issues after enabling the server
Install
Copy the command and run it in a terminal.
npx skills add https:/After installing, type/msbuild-serverin Claude Code to confirm it loaded.
Details
From the project READMEMSBuild Server for CLI Caching
Use the MSBuild Server to cache evaluation results across CLI builds, matching the performance advantage Visual Studio gets from its long-lived MSBuild process.
When to Use
- Small incremental builds from CLI (
dotnet build) are slower than expected - Developers notice that VS builds are faster than CLI builds for the same project
- CI agents run many sequential builds of the same repo
When Not to Use
- IDE-based builds (Visual Studio already uses a long-lived MSBuild process)
- One-off builds where cold-start overhead is acceptable
- Build correctness issues are suspected (disable the server to isolate the problem)
Inputs
| Input | Required | Description |
|---|---|---|
| Shell context | No | The shell where the environment variable will be set (bash, PowerShell, or Windows persistent) |
Workflow
Step 1: Confirm CLI context
Verify the developer is building from the command line (dotnet build), not from Visual Studio or another IDE. The MSBuild Server provides no benefit inside an IDE.
Step 2: Set the environment variable
# Bash / CI
export MSBUILDUSESERVER=1
# PowerShell
$env:MSBUILDUSESERVER = "1"
# Windows (persistent)
setx MSBUILDUSESERVER 1
Step 3: Validate improvement
Run two sequential builds of the same project and compare times:
- First build (cold):
dotnet build-- server starts, no cache benefit - Second build (warm):
dotnet build-- should be noticeably faster
The most noticeable improvement is in repos with many projects or complex Directory.Build.props chains.
Validation
-
MSBUILDUSESERVER=1is set in the shell - Second sequential build is faster than the first
-
dotnet build-server shutdownfollowed by a rebuild confirms the server restarts cleanly
Common Pitfalls
| Pitfall | Solution |
|---|---|
| Expecting improvement in Visual Studio | VS already uses long-lived MSBuild nodes; the server adds no benefit |
| Build correctness issues after enabling | Run dotnet build-server shutdown to reset; if issues persist, disable the server |
| Server process using unexpected memory | The server persists in background; shut down with dotnet build-server shutdown when idle |