Source Mix

SourceMix turns selected C# source files into a single Markdown context file that is easier to hand to an LLM. You can use it in two ways from the same installed dotnet tool:

• CLI mode for scripted or repeatable runs
• TUI mode for interactive file picking and option selection

The tool can include just the files you select, or expand outward to referenced source types, optional decompiled dependency types, reusable skills, and a final prompt block.

Install

Install the tool globally from NuGet:

dotnet tool install --global HenrikJensen.SourceMix

After that, use the sourcemix command.

Update an existing installation:

dotnet tool update --global HenrikJensen.SourceMix

Uninstall it:

dotnet tool uninstall --global HenrikJensen.SourceMix

Quick start

Use the interactive experience when you want help choosing files:

sourcemix tui

Use the CLI when you already know the files or patterns you want:

sourcemix "src/**/*.cs" -o context.md

TUI usage

Run the TUI from any directory containing a .sln or .slnx file:

sourcemix tui

Wizard flow

1. Search and select files — type to filter .cs files by name in real time, move with ↑↓, toggle with Space, pin with Ctrl+P, confirm with Enter, and switch views with Tab.
2. Configure options — choose recursive dependency resolution, optional depth limiting, decompilation of compiled types, whether dependency method bodies should be trimmed, and whether var / target-typed new() should be expanded to inferred types.
3. Select prompt — optionally append a built-in or custom prompt to the generated output.
4. Select skills — optionally prepend one or more SKILL.md instruction files.
5. Generate — write the final Markdown output and persist your preferences for the next run.

Note: --include-compiled depends on assemblies that already exist in bin/, so run dotnet build first.

CLI usage

sourcemix [<files>...] [--output <path>] [--recursive] [--depth <n>] [--include-compiled] [--trim] [--expand-types]

Arguments

• <files> — one or more file paths or glob patterns such as src/**/*.cs

Options

• -o, --output <path> — write output to a file instead of stdout
• -r, --recursive — include files that define referenced types
• -d, --depth <n> — limit recursion depth when --recursive is used
• -c, --include-compiled — decompile unresolved referenced interfaces/models from compiled assemblies; requires --recursive
• -t, --trim — trim dependency method bodies while keeping signatures; requires --recursive
• -e, --expand-types — replace var with the inferred type and expand target-typed new() to include the type; anonymous types, tuple deconstruction, and unresolved cases are left unchanged
• -p, --prompt <name-or-text> — append a built-in prompt key or custom prompt text
• -s, --skills <key>... — prepend one or more skills by key

Built-in prompts

• nunit-test
• xunit-test
• code-review
• tech-docs
• explain
• debug
• refactor
• architecture

Examples

# Write a context file from a glob
sourcemix "src/**/*.cs" -o context.md

# Print selected files to stdout
sourcemix Foo.cs Bar.cs Baz.cs

# Pull in referenced source types and decompiled unresolved types
sourcemix MyService.cs -r -c -o context.md

# Trim dependency bodies and append an xUnit-focused prompt
sourcemix MyService.cs -r -t --prompt xunit-test -o context.md

# Expand inferred types before writing the context file
sourcemix MyService.cs -r -e -o context.md

# Add skills plus a code review prompt
sourcemix MyService.cs -r -t --skills unit-test-style architecture-rules --prompt code-review -o context.md

Preferences

SourceMix stores per-solution preferences after TUI runs, including pinned files, pinned skills, output path, last-used prompt, and default options.

Platform	Location
Windows	%APPDATA%\sourcemix\sourcemix-<hash>.json
Linux	~/.config/sourcemix/sourcemix-<hash>.json
macOS	~/.config/sourcemix/sourcemix-<hash>.json

Global custom prompts are stored separately:

Platform	Location
Windows	%APPDATA%\sourcemix\sourcemix-global.json
Linux	~/.config/sourcemix/sourcemix-global.json
macOS	~/.config/sourcemix/sourcemix-global.json

Skills

Skills are reusable Markdown instructions inserted before the collected code. Each skill lives in its own directory and must contain a SKILL.md file. A skill file cannot reference other files.

Platform	Location
Windows	%APPDATA%\sourcemix\skills\
Linux	~/.config/sourcemix/skills/
macOS	~/.config/sourcemix/skills/

Example:

~/.config/sourcemix/skills/
  unit-test-style/
    SKILL.md
  architecture-rules/
    SKILL.md

Local development

Restore tools and dependencies:

dotnet tool restore
./scripts/restore.bash

Build with the repository checks:

./scripts/build.bash

Run the tests:

./scripts/test.bash

Run the benchmarks to measure performance and detect regressions:

./scripts/benchmark.bash

Results are saved to tmp/benchmark-latest.md after each run. The previous run is kept as tmp/benchmark-previous.md for comparison.

Create the release package:

./scripts/pack.bash

Pack and publish

Create the NuGet package:

./scripts/pack.bash

The package is written to:

src/SourceMix/bin/Release/HenrikJensen.SourceMix.<version>.nupkg

Install that package locally for validation:

dotnet tool install --global --add-source ./src/SourceMix/bin/Release HenrikJensen.SourceMix

Publish it to NuGet:

dotnet nuget push src/SourceMix/bin/Release/HenrikJensen.SourceMix.<version>.nupkg --source https://api.nuget.org/v3/index.json --api-key <api-key>

pack.bash only creates the Release package. Run ./scripts/build.bash and ./scripts/test.bash separately as your validation steps before publishing.