Can different folders have different review rules?

Yes. Configure any folder with its own rules, review options and noise settings. If a pull request touches two configured folders, Mesrai uses the repository configuration to stay predictable.

Does Mesrai work with Nx, Turborepo or Bazel?

Yes. Configuration is based on folders, so it works with any monorepo tool.

How does Mesrai catch breaking changes in shared code?

It builds a repository graph from the syntax tree and checks where changed exports are imported across the monorepo.

All use cases

Use case · Monorepos

Precise review for every package in your monorepo.

A monorepo holds a frontend, a backend, shared libraries and infrastructure — each with different standards. Mesrai applies the right rules to each folder and follows changes across package boundaries.

Config levels: Org → repo → folder
Cross-package: Graph-aware
Works with: Nx, Turborepo, Bazel

Start free See examples

How monorepo teams use AI code review

Monorepo teams use AI code review with directory-level configuration: each app or package gets its own rules, review options and noise settings, inherited from organization and repository defaults. Mesrai's repository graph follows imports across packages, so a change to a shared library is reviewed for its effect on every app that uses it.

Why monorepos are hard to review

01
One set of review settings is too strict for one package and too loose for another.
02
A small change in a shared library can break apps owned by other teams.
03
Reviewers know their own package, not the dependents of the code they're approving.
04
Pull requests that touch several packages mix concerns and standards.

II.

How Mesrai handles monorepos

Directory-level settings

Configure any folder with its own rules, review options, severity filters and ignored paths. Each pull request uses one predictable configuration.

Rule inheritance

Organization rules apply everywhere; repository rules for the monorepo; folder rules for each package.

Cross-package impact

The repository graph shows which apps import the changed shared code.

File references in rules

Point rules at the source of truth, e.g. @file:libs/ui/src/tokens.ts for design tokens.

III.

Real-world scenarios

2 examples

Illustrative examples of the kind of change monorepo teams make every week, and the review comment Mesrai would post.

Scenario 01

A breaking change in a shared library

A developer renames a field in libs/shared/types to fix a typo, updating the API app but not the others.

libs/shared/src/types/order.ts

export interface Order {
  id: string;
  totalAmount: number; // was: totalAmmount
}

MesraiBug agentMUST_FIX

apps/web/src/orders/OrderRow.tsx and apps/mobile/src/screens/Checkout.tsx still read order.totalAmmount, so they'll show undefined after this change. Update them in this PR or keep a deprecated alias.

Result: The breakage in two other apps is caught before merge, not by those teams' users.

Scenario 02

Design tokens in the web app

A new React component in apps/web hardcodes colours.

MesraiMesrai RulesSUGGESTION

Rule for apps/web: components must use design tokens from libs/ui/src/tokens.ts. Replace #1f2937 with tokens.color.gray[800].

Result: The frontend's rule applies only to frontend code; the backend isn't flooded with irrelevant comments.

IV.

Set up a monorepo

Map packages to review needs, then configure folders. The 'Mesrai for monorepos' recipe has the full walkthrough.

1
List your packages and their standards (web, api, mobile, shared libs, infra).
2
Put shared rules at organization or repository level.
3
Configure each package folder with its own rules and review options.
4
Use @file references so rules point at the code that defines the standard.

Folder rule for a frontend package

Name: React components must use design system tokens
Scope: File
Paths: apps/web/src/components/**/*.tsx
Severity: High
Instructions:
  Flag hardcoded colours, spacing or font sizes.
  Use tokens from @file:libs/ui/src/tokens.ts.

Who uses it, and how

Package owners: Own the rules for their folder without affecting other teams.
Platform team: Sets monorepo-wide defaults and watches shared-library changes.

VI.

What teams achieve

Relevant rules for each package

Shared-library changes reviewed for their dependents

Less noise from rules that don't apply

Standards tied to the code that defines them

VII.

Monorepos — frequently asked

3 questions

Can different folders have different review rules?
+
Yes. Configure any folder with its own rules, review options and noise settings. If a pull request touches two configured folders, Mesrai uses the repository configuration to stay predictable.
Does Mesrai work with Nx, Turborepo or Bazel?
+
Yes. Configuration is based on folders, so it works with any monorepo tool.
How does Mesrai catch breaking changes in shared code?
+
It builds a repository graph from the syntax tree and checks where changed exports are imported across the monorepo.

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