DSoftStudio Mediator Pipeline Explorer for Visual Studio

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.}

Free trial — full access to every commercial feature while you evaluate it against your own codebase. Start your trial →

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

1. Open the controller that dispatches CheckLicenseCommand.
2. Jump to the command type from the tool window — instant.
3. Inspect the behavior chain: validation → caching → authorization → handler. Open any of them.
4. Visualize the request graph: see the notification fan-out and the nested RegisterGrantCommand that fires inside the handler.
5. Start runtime profiling. Issue requests against your local API.
6. Spot a tail-heavy validation behavior at p99 — 380 ms while the median is 4 ms.
7. 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 the exception-handler branch, notification fan-out, and nested mediator calls drawn inline. Every node carries its live average duration and a heat badge (fast / slow), so the bottleneck is obvious at a glance. Pan, zoom, click any node to navigate or inspect — full WPF rendering, no embedded browser.

_{The full pipeline for a command — pre-processors, behaviors, handler, post-processors, and the exception branch — with per-node average timings and heat coloring, plus the tree and detail panel above.}

Runtime profiler

Live handler and behavior timings in the Runtime Profiler panel — p50 / p95 / p99 percentiles, error rates, tail-heavy detection. The Hot Path view breaks one request into its exact execution order and attributes every millisecond: each pre-processor, behavior, and the handler, plus the external dependencies underneath it — EF Core compile/connect, the individual SQL statements (INSERT orders, SELECT inventory), HTTP calls — and the self-wait (time lost to I/O / async scheduling rather than CPU). A bottleneck badge flags the row that dominates. 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.

_{Hot Path: per-component timings, external dependency attribution (EF Core / PostgreSQL), and self-wait — with the dominant row flagged automatically.}

Zoom out to the statistics dashboard for the whole session: per-pipeline Calls / Errors / Avg / P50 / P95 / P99 / Max, notification fan-out with per-handler overhead, and live request telemetry (fastest / slowest / tail factor / worst-P99 pipeline).

_{Per-pipeline percentiles, notification fan-out overhead, and live telemetry across the profiling session.}

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
• A license or a free trial — the extension asks for one on first run

Getting started

1. Install the extension from the Visual Studio Marketplace, or via Extensions → Manage Extensions → Online.
2. Restart Visual Studio when prompted — the VSIX installer requires a restart to load the analyzers.
3. Open a solution containing a project that references DSoftStudio.Mediator. Then open View → Other Windows → Mediator Pipeline Explorer. The tree populates automatically.
4. Activate your license — use the activation flyout in the tool window toolbar. Paste your token and click Activate.
5. 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.

Tool window layout

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.

Toolbar actions

Current platform limitations

• Solution-rooted only. Standalone .csproj files outside a solution are not yet auto-detected.
• Profiler attach is solution-scoped. The profiler attaches to apps launched from the IDE or already running outside it (e.g. dotnet run in a terminal), but it only considers processes that belong to the open solution — it never lists or attaches to unrelated processes on the machine.
• 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.

• Pricing & free trial: https://mediator.dsoftstudio.com/pricing?src=vs-readme-footer
• Documentation: https://docs.dsoftstudio.com/mediator/pipeline-explorer/
• Issues & feature requests: https://github.com/DSoftStudio/Mediator/issues
• Licensing inquiries: licensing@dsoftstudio.com

_{DSoftStudio Mediator is a registered product of DSoftStudio. Visual Studio is a trademark of Microsoft Corporation.}