diff --git a/packages/eslint-plugin/lib/configs/internal.js b/packages/eslint-plugin/lib/configs/internal.js
index 17cc652059..79ba090b5a 100644
--- a/packages/eslint-plugin/lib/configs/internal.js
+++ b/packages/eslint-plugin/lib/configs/internal.js
@@ -49,6 +49,17 @@ module.exports = {
     // RESM does not support ?? nor ?. operators, so we must avoid them expressly.
     '@endo/no-optional-chaining': 'error',
     '@endo/no-nullish-coalescing': 'error',
+    '@typescript-eslint/naming-convention': [
+      'error',
+      {
+        selector: 'interface',
+        format: ['PascalCase'],
+        custom: {
+          regex: '.*I$',
+          match: false,
+        },
+      },
+    ],
   },
   overrides: [
     {
diff --git a/packages/pass-style/src/types.d.ts b/packages/pass-style/src/types.d.ts
index fdcd419a74..346eac0ab3 100644
--- a/packages/pass-style/src/types.d.ts
+++ b/packages/pass-style/src/types.d.ts
@@ -85,14 +85,14 @@ export type Passable<
 > = void | Primitive | Container<PC, E> | PC | E;
 
 export type Container<PC extends PassableCap, E extends Error> =
-  | CopyArrayI<PC, E>
-  | CopyRecordI<PC, E>
-  | CopyTaggedI<PC, E>;
-interface CopyArrayI<PC extends PassableCap, E extends Error>
+  | CopyArrayInterface<PC, E>
+  | CopyRecordInterface<PC, E>
+  | CopyTaggedInterface<PC, E>;
+interface CopyArrayInterface<PC extends PassableCap, E extends Error>
   extends CopyArray<Passable<PC, E>> {}
-interface CopyRecordI<PC extends PassableCap, E extends Error>
+interface CopyRecordInterface<PC extends PassableCap, E extends Error>
   extends CopyRecord<Passable<PC, E>> {}
-interface CopyTaggedI<PC extends PassableCap, E extends Error>
+interface CopyTaggedInterface<PC extends PassableCap, E extends Error>
   extends CopyTagged<string, Passable<PC, E>> {}
 
 export type PassStyleOf = {