Exclusive branch links

noExclusiveLink(a, b) checks that two branches do not depend on each other through a private leak. Shared kernel nodes are allowed:

export function keepFeatureBranchesIndependent(graph: ArchitectureGraph) {
  noExclusiveLink(graph.route('/admin'), graph.route('/checkout'));
}

What it prevents

Suppose two features are intended to be independent:

admin → checkout-private-service → checkout

The application has now created a hidden integration. A future checkout rewrite must preserve an admin-only dependency, and removing the link can break a route that was never listed as a consumer.

The same problem appears between feature services:

UserList → UserMutation → UserList

or when one route reaches directly into another feature's private data service.

Shared kernels are not leaks

This is allowed:

admin    → Auth
checkout → Auth

The helper stops membership at other provides sites, so a common auth service, HTTP boundary or browser boundary is treated as shared infrastructure rather than as a feature-to-feature link.

Use it with routes or services

The arguments are graph nodes, so the same invariant can protect route branches, feature services or any two catalog lookups.

See also

• Path boundaries
• Architecture graph lookups