diff --git a/packages/common/src/index.ts b/packages/common/src/index.ts
index 6f087a3b22..f42a47ee7e 100644
--- a/packages/common/src/index.ts
+++ b/packages/common/src/index.ts
@@ -1,8 +1,8 @@
 export * from "./cursorlessCommandIds";
 export * from "./testUtil/extractTargetedMarks";
 export { default as FakeIDE } from "./ide/fake/FakeIDE";
-export { Message } from "./ide/spy/SpyMessages";
-export { SpyIDERecordedValues } from "./ide/spy/SpyIDE";
+export type { Message } from "./ide/spy/SpyMessages";
+export type { SpyIDERecordedValues } from "./ide/spy/SpyIDE";
 export { default as SpyIDE } from "./ide/spy/SpyIDE";
 export { HatStability } from "./ide/types/HatStability";
 export * from "./util";
@@ -11,8 +11,9 @@ export { getKey, splitKey } from "./util/splitKey";
 export { hrtimeBigintToSeconds } from "./util/timeUtils";
 export * from "./util/walkSync";
 export * from "./util/walkAsync";
-export { Listener, Notifier } from "./util/Notifier";
-export { TokenHatSplittingMode } from "./ide/types/Configuration";
+export { Notifier } from "./util/Notifier";
+export type { Listener } from "./util/Notifier";
+export type { TokenHatSplittingMode } from "./ide/types/Configuration";
 export * from "./ide/types/ide.types";
 export * from "./ide/types/Capabilities";
 export * from "./ide/types/CommandId";
diff --git a/tsconfig.base.json b/tsconfig.base.json
index 059d1cb50e..80f180cc27 100644
--- a/tsconfig.base.json
+++ b/tsconfig.base.json
@@ -10,6 +10,7 @@
     "resolveJsonModule": true,
     "composite": true,
     "forceConsistentCasingInFileNames": true,
+    "isolatedModules": true,
     "strict": true
   }
 }