Architectural and runtime observability for DSoftStudio.Mediator — directly inside Visual Studio.
See every request handler, behavior, pre/post-processor, notification dispatch, and stream — wired into the source it came from, with live profiling stats and one-click navigation.
Screenshot: tool window with tree, detail panel, and interactive graph of a real CQRS solution.
Why Pipeline Explorer?
Mediator-heavy applications grow fast and become hard to reason about:
- Hidden behaviors silently wrap every dispatch — validation, logging, retry, transactions — and nobody remembers the chain.
- Nested mediator calls inside handlers turn a single endpoint into a dozen invocations the IDE won't show you.
- Notification fan-out scatters business effects across projects; tracing them needs grep and luck.
- Performance bottlenecks hide behind generic pipeline traces — which behavior is the slow one, on which request?
- Cross-project handlers live in
*.Application, dispatched from *.Api, decorated in *.Infrastructure — no single source file tells the story.
Pipeline Explorer gives you a real-time architectural and runtime view of the mediator graph as it exists in your codebase, with the source under one click and live timing data under another.
Example workflow
- Open the controller that dispatches
CheckLicenseCommand.
- Jump to the command type from the tool window — instant.
- Inspect the behavior chain: validation → caching → authorization → handler. Open any of them.
- Visualize the request graph: see the notification fan-out and the nested
RegisterGrantCommand that fires inside the handler.
- Start runtime profiling. Issue requests against your local API.
- Spot a tail-heavy validation behavior at p99 — 380 ms while the median is 4 ms.
- Click the behavior in the Runtime Profiler panel — jumps to source. Fix it. Re-run.
That loop — understand → navigate → measure → fix — without ever leaving the IDE.
Capabilities
Pipeline tree explorer
A dedicated tool window grouping every request pipeline by kind — Commands, Queries, Notifications, Streams — with at-a-glance badges (Command · PassThrough, Query · Full, notification fan-out count, stream kind). Native VS theming, light / dark / high-contrast supported out of the box.
Click-to-source navigation
Every node knows where it lives. Click a handler — opens the document at the right line. Click a behavior — same. Click a call site — opens the controller / endpoint that dispatched the request. Right-click for Go to Definition / Find All References parity with the rest of the IDE.
Interactive pipeline graph
Per-pipeline visualization of pre-processors → behaviors → handler → post-processors, with notification fan-out and nested mediator calls drawn inline. Pan, zoom, click any node to navigate or inspect — full WPF rendering, no embedded browser.
Runtime profiler
Live handler and behavior timings in the Runtime Profiler panel — p50 / p95 / p99 percentiles, error rates, tail-heavy detection. Snapshot, clear, export. The profiling hooks wire themselves into your application at compile time the moment the analyzer is loaded, so there is nothing to add to Program.cs. This is where the largest day-to-day ROI lives — pinpointing the one slow behavior in a dozen-deep chain takes seconds, not an afternoon of OpenTelemetry digging.
CQRS-aware view
Pipelines tagged automatically by interface (ICommand<>, IQuery<>, IRequest<>) so the tree groups them the way your codebase actually thinks. Dedicated icons distinguish reads from writes at a glance; the section filter dropdown narrows the view in one click.
Zero-config discovery
Open a solution and the extension scans your projects, finds every IRequestHandler / IStreamRequestHandler / INotificationHandler, and builds the tree. No registration, no attributes, no MSBuild hooks beyond the analyzer NuGet you already reference.
Requirements
- Visual Studio 2022 17.0+ or Visual Studio 2026 (Community, Professional, or Enterprise)
- .NET Framework 4.8 runtime (bundled with VS)
- .NET 8 or 10 in the target solution
- DSoftStudio.Mediator referenced by the project(s) you want to inspect
Getting started
- Install the extension from the Visual Studio Marketplace, or via
Extensions → Manage Extensions → Online.
- Restart Visual Studio when prompted — the VSIX installer requires a restart to load the analyzers.
- Open a solution containing a project that references
DSoftStudio.Mediator. Then open View → Other Windows → Mediator Pipeline Explorer. The tree populates automatically.
- Activate your license — use the activation flyout in the tool window toolbar. Paste your token and click
Activate.
- Enable runtime profiling (optional) — click
Start in the tool window toolbar. The profiler is wired into your application automatically by the analyzer; no code change is required. Live stats flow into the Runtime Profiler panel.
The Pipeline Explorer ships as a single tool window with three regions:
- Toolbar — refresh, profiling start / stop / snapshot / clear, section filter, search box, settings, license status.
- Tree (left) — Request Pipelines, Notifications, Streams. Right-click any node for navigation, copy, pin, and graph actions.
- Detail panel (right) — selected pipeline's pre/post-processors, behaviors, handler metadata, call sites, runtime stats. The interactive graph panel toggles below the detail (vertical split).
Settings live behind the gear icon and persist per-user via the standard VS settings store.
| Action |
What it does |
| Refresh |
Re-scan the solution; resets cached profiling data |
| Start / Stop |
Attach or detach the runtime profiler |
| Snapshot |
Capture a point-in-time snapshot of the current session |
| Clear |
Drop all in-memory profiling state |
| Settings |
Toggle name format, lifetime badges, pipeline-mode badges, nested-operation rendering, etc. |
| License |
Open the activation flyout |
| Graph |
Show / hide the interactive graph panel |
- Solution-rooted only. Standalone
.csproj files outside a solution are not yet auto-detected.
- In-process profiler only. Out-of-process attach is on the roadmap.
- Single solution per IDE window. Re-opening a solution refreshes the cache cleanly.
- Light-weight type resolution. Generic constraint chains and conditional DI registrations may not always resolve to a concrete handler; the analyzer warns when ambiguous.
- WPF rendering. Hosts running VS through remote desktop or virtual graphics may see graph-panel redraw lag on very large pipelines (>500 nodes).
We track these — and accept bug reports — at the GitHub repository.
Licensing
Pipeline Explorer is commercial software. A free trial is available so you can validate the workflow against your real codebase before purchasing. After the trial window, a valid activation token is required to continue using the extension.
DSoftStudio Mediator is a registered product of DSoftStudio. Visual Studio is a trademark of Microsoft Corporation.
