Shader Variant Budget & CI Guard

Shader Variant Budget & CI Guard helps Unity teams find, understand, and stop shader variant regressions before those regressions turn into bigger build problems. Instead of guessing why variant counts suddenly went up, you can capture snapshots, compare builds, and see exactly what changed. The tool is made for developers who want a clear workflow, not a vague warning after the damage is already done.

The core job of this tool is simple: it tracks shader variant counts over time and tells you when they move in the wrong direction. After a build, it reads the variant data from Editor.log, saves a deterministic snapshot, and lets you compare a baseline build against a current build. You can quickly see total variant changes, per-shader changes, new entries, removed entries, and where the biggest increases came from.

This matters because shader variant growth is easy to miss. A project can look fine for weeks, then slowly collect extra variants through shader changes, keyword changes, package updates, or content changes across teams. By the time someone notices, the project may already have slower build iteration, harder debugging, and a less predictable pipeline. This tool gives you a practical guardrail so shader variants stay visible and controlled.

Inside the Unity Editor, the workflow is built to be direct and easy to use. You open the Shader Variant Guard window, capture or load snapshots, choose a baseline and current result, and run a comparison. The results are shown with summary cards, filtered diff views, search tools, sorting, and diagnostics. That means you do not need to dig through raw logs by hand just to answer basic questions like “what changed?” or “which shader caused this jump?”

The budget system is where this becomes a real production tool, not just a viewer. You can define hard limits and warning limits for total variants, delta variants, percent delta, and per-shader counts. When the current snapshot breaks those rules, the tool reports the problem clearly. You can also add ignore rules and allow rules so the results stay focused on the shader changes that actually matter to your team.

For teams working in CI, this tool is built to gate builds automatically. It includes a batchmode runner with stable exit codes, external JSON budget support, report export options, and a latest-passing baseline workflow. In practice, that means you can run it in automated validation and fail a build when shader variant counts cross the limits you defined. Instead of noticing regressions later, your pipeline can stop them at the point where they are introduced.

Baseline management is handled with real production needs in mind. The tool can compare against the latest snapshot, the latest passing snapshot, or a specific snapshot path. It also supports profile-aware baseline matching, latest-passing index overrides, and optional baseline promotion in CI. This makes it useful for teams that need a repeatable baseline workflow across multiple branches, build targets, or build profiles.

The tool also protects you from low-quality data. If a snapshot is incomplete, the guard can detect that and fail the check instead of silently giving you bad results. This is important because a broken or partial snapshot can hide a real regression. The incomplete-snapshot gating makes the tool more reliable when used in automated environments where confidence in the data matters.

The editor experience is practical, not bloated. Settings are available in Project Settings, with normal and advanced sections, browse buttons for paths, clear controls for storage and retention, and guidance for unusual values. The main window supports snapshot-first comparisons, filtering, search, diff tabs, and diagnostics export. There is also a one-click Generate Example Test Workflow action so you can seed realistic sample data and understand the tool fast.

This asset is a strong fit if your project has grown past the point where manual checking is enough. If you are shipping on multiple targets, working with a team, reviewing build health in CI, or trying to stop shader complexity from creeping up over time, this tool gives you structure and visibility. It is especially useful when you want to turn shader variant control into a repeatable process instead of relying on memory, guesswork, or occasional cleanup passes.

What you are really buying is control. You get a way to measure shader variant changes, compare builds with confidence, define budgets that match your project, and enforce those budgets both in the Editor and in CI. If shader variants have ever felt like a hidden problem in your pipeline, Shader Variant Budget & CI Guard turns them into something visible, trackable, and manageable.