Now supporting GitLab & GitHub

FSD review right in your browser — before the code hits main

The architecture linter that lives in your Pull Request. No CI, no setup, and absolutely no code leaving your browser.

Install for Google Chrome

Extension for Chrome, Brave & Edge. 100% Local & Private.

FSD Guard reviewing a GitHub Pull Request: inline diff with a public-API-bypass violation and the FSD Guard details panel
The Problem

Why Feature-Sliced Design breaks in practice

Maintaining architectural guidelines is notoriously hard. Without automation, guidelines quickly erode under velocity pressure.

Rule Evasion

Rules only live in your head

FSD's layer isolation guides are dense. Developers easily forget whether Features can import from Entities, leading to quiet dependency spaghetti.

Review Bottleneck

Manual review doesn't scale

Checking imports line-by-line during PR reviews is exhaustively tedious. Violations slip past reviewers focused purely on business logic.

Setup Fatigue

CI linters are heavy & slow

Configuring ESLint / Steiger rules in CI blocks developer pipelines, takes weeks to approve, and slows down local build performance.

Two Modes. Zero Setup.

Designed for instant architectural sanity

PR Inline Check Mode

The extension injects warning banners directly beneath offending lines inside GitHub & GitLab diff views. Developers resolve violations before even requesting review.

PR inline check mode — warning banners injected beneath offending lines in a GitHub diff

Full Repository Audit

Click the extension icon on any repository to instantly analyze the entire codebase. Generate a high-level map of current layer dependencies and clean up legacy violations.

Full repository audit — layer dependency violations listed for an entire codebase
Simple Flow

From install to feedback in 15 seconds

Zero integrations, zero packages to install. Just extension magic.

The FSD Guard browser extension popup showing an instant violation summary

The FSD Guard popup — instant violation summary, right in your browser

1

Install Extension

Add FSD Guard to your Chromium-based browser in one-click from the Web Store.

2

Open any Pull Request

Navigate to any GitHub or GitLab Pull/Merge Request. No repo token or API key required.

3

See violations inline

Offending import lines are marked with clean, actionable architectural warnings.

Capabilities

Superpowered FSD analysis features

Inline diff highlighting

Violations are illuminated inside standard git diff viewports. Fits smoothly into your routine.

Deep Details Panel

Hover any violation to understand the structural logic behind why FSD restricts the import.

Copy for AI assistants

Export violations instantly in an optimized prompt format for ChatGPT, Claude, or Copilot.

Instant Repository Audit

Get a comprehensive FSD index score for any codebase in seconds, from open source to enterprise.

Multi-language core

Fully supports TypeScript, JavaScript, Vue, Svelte, and experimental framework setups.

Flexible configuration

Uses custom alias rules and layers if your codebase adapts the FSD standard.

FSD Ruleset

What FSD Guard checks automatically

We validate your imports against the core pillars of Feature-Sliced Design specifications.

01

Layer Hierarchy

Layers can only import from lower-level layers (e.g. Page → Feature, never vice-versa).

Strict Validation
02

Slice Isolation

Slices within the same layer cannot import from each other to prevent tight coupling.

Violations Highlighted
03

Public API Protection

Imports must traverse the public API (index.ts) of slices rather than internal files.

Strict Validation
04

Internal Cross-Imports (@x)

Identifies and flags circular references utilizing aliases or internal sub-paths.

Cross-Import Guard
Alternatives

How FSD Guard stacks up

Setup Required
FSD Guard ExtensionZero (Browser only)
ESLint / Steiger (CI)Weeks of config
Manual Code ReviewNone
Analyze Third-Party Repos
FSD Guard ExtensionYes (Any open PR)
ESLint / Steiger (CI)No
Manual Code ReviewYes (Slowly)
Feedback Speed
FSD Guard ExtensionInstant on-page load
ESLint / Steiger (CI)CI pipeline lag
Manual Code ReviewReview meeting delay
Violation Explanations
FSD Guard ExtensionDetailed interactive tooltips
ESLint / Steiger (CI)Generic terminal text
Manual Code ReviewDepends on reviewer
One-click AI Export
FSD Guard ExtensionBuilt-in copy formatter
ESLint / Steiger (CI)Manual copy-paste
Manual Code ReviewNo
Privacy Shielding
FSD Guard Extension100% Local
ESLint / Steiger (CI)Variable
Manual Code ReviewCode leaked online
Who is it for

Fitted for high-velocity teams

For Leads

Accelerated Code Review

Lead engineers delegate architectural audits to the extension, saving cognitive power for business critical functions.

For Onboarding

Junior Dev Onboarding

Guide newer engineers through practical FSD structure organically. Feedback arrives inside PR drafts, before reviews.

For Maintenance

Legacy Repository Auditing

Evaluate code health instantly when inheriting un-typed projects or reviewing freelance deliveries.

For Open Source

Quick Third-Party Assessments

Explore architecture quality inside external open source PRs before integrating libraries into your ecosystem.

Your code never leaves your browser

FSD Guard processes all validation internally inside your browser context. We operate no cloud analytics servers, collect zero telemetry, and capture no code files. Safe for highly restricted corporate repositories.

  • No API keys needed
  • 100% Local logic
  • No remote servers