binlog-generation

Original：🇺🇸 English

Translated

Generate MSBuild binary logs (binlogs) for build diagnostics and analysis. Only activate in MSBuild/.NET build context. USE FOR: adding /bl:{} to any dotnet build, test, pack, publish, or restore command to capture a full build execution trace, prerequisite for binlog-failure-analysis and build-perf-diagnostics skills, enabling post-build investigation of errors or performance. Requires MSBuild 17.8+ / .NET 8 SDK+ for {} placeholder; PowerShell needs -bl:{{}}. DO NOT USE FOR: non-MSBuild build systems (npm, Maven, CMake), analyzing an existing binlog (use binlog-failure-analysis instead). INVOKES: shell commands (dotnet build /bl:{}).

2installs

Sourcedotnet/skills

Added on2026-03-26

NPX Install

npx skill4agent add dotnet/skills binlog-generation

SKILL.md Content

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Generate Binary Logs

Pass the
/bl
switch when running any MSBuild-based command. This is a non-negotiable requirement for all .NET builds.

Commands That Require /bl

You MUST add the

/bl:{}

flag to:

```
dotnet build
```
```
dotnet test
```
```
dotnet pack
```
```
dotnet publish
```
```
dotnet restore
```
```
msbuild
```
or
```
msbuild.exe
```
Any other command that invokes MSBuild

Preferred: Use

{}

for Automatic Unique Names

Note: The
{}
placeholder requires MSBuild 17.8+ / .NET 8 SDK or later.

The

{}

placeholder in the binlog filename is replaced by MSBuild with a unique identifier, guaranteeing no two builds ever overwrite each other — without needing to track or check existing files.

bash

# Every invocation produces a distinct file automatically
dotnet build /bl:{}
dotnet test /bl:{}
dotnet build --configuration Release /bl:{}

PowerShell requires escaping the braces:

powershell

# PowerShell: escape { } as {{ }}
dotnet build -bl:{{}}
dotnet test -bl:{{}}

Why This Matters

Unique names prevent overwrites - You can always go back and analyze previous builds
Failure analysis - When a build fails, the binlog is already there for immediate analysis
Comparison - You can compare builds before and after changes
No re-running builds - You never need to re-run a failed build just to generate a binlog

Examples

bash

# ✅ CORRECT - {} generates a unique name automatically (bash/cmd)
dotnet build /bl:{}
dotnet test /bl:{}

# ✅ CORRECT - PowerShell escaping
dotnet build -bl:{{}}
dotnet test -bl:{{}}

# ❌ WRONG - Missing /bl flag entirely
dotnet build
dotnet test

# ❌ WRONG - No filename (overwrites the same msbuild.binlog every time)
dotnet build /bl
dotnet build /bl

When a Specific Filename Is Required

If the binlog filename needs to be known upfront (e.g., for CI artifact upload), or if

{}

is not available in the installed MSBuild version, pick a name that won't collide with existing files:

Check for existing
```
*.binlog
```
files in the directory
Choose a name not already taken (e.g., by incrementing a counter from the highest existing number)

bash

# Example: directory contains 3.binlog — use 4.binlog
dotnet build /bl:4.binlog

Cleaning the Repository

When cleaning the repository with

git clean

, always exclude binlog files to preserve your build history:

bash

# ✅ CORRECT - Exclude binlog files from cleaning
git clean -fdx -e "*.binlog"

# ❌ WRONG - This deletes binlog files (they're usually in .gitignore)
git clean -fdx

This is especially important when iterating on build fixes - you need the binlogs to analyze what changed between builds.

binlog-generation

NPX Install

Tags

SKILL.md Content

Generate Binary Logs

Commands That Require /bl

Preferred: Use
`{}`
for Automatic Unique Names

Why This Matters

Examples

When a Specific Filename Is Required

Cleaning the Repository