diff --git a/packages/core/src/Extension.ts b/packages/core/src/Extension.ts
index da45fa441..6b22e0436 100644
--- a/packages/core/src/Extension.ts
+++ b/packages/core/src/Extension.ts
@@ -1,4 +1,4 @@
-import { Editor } from './Editor'
+import { Editor, Command } from './Editor'
 
 export default abstract class Extension {
 
@@ -39,11 +39,11 @@ export default abstract class Extension {
     return []
   }
 
-  keys(): { [key: string]: any } {
+  keys(): string | { [key: string]: Function } {
     return {}
   }
 
-  commands(): { [key: string]: any } {
+  commands(): { [key: string]: Command } {
     return {}
   } 
 
diff --git a/packages/core/src/ExtensionManager.ts b/packages/core/src/ExtensionManager.ts
index 9b81746fd..0e7645cc7 100644
--- a/packages/core/src/ExtensionManager.ts
+++ b/packages/core/src/ExtensionManager.ts
@@ -79,7 +79,17 @@ export default class ExtensionManager {
 
   get keymaps() {
     return collect(this.extensions)
-      .map(extension => extension.keys())
+      .map(extension => {
+        const keys = extension.keys()
+
+        if (typeof keys === 'string') {
+          return {
+            [keys]: () => this.editor.command(extension.name)
+          }
+        }
+
+        return keys
+      })
       .filter(keys => !!Object.keys(keys).length)
       .map(keys => keymap(keys))
       .toArray()
diff --git a/packages/extension-bold/index.ts b/packages/extension-bold/index.ts
index e40a20db5..349a9c2e8 100644
--- a/packages/extension-bold/index.ts
+++ b/packages/extension-bold/index.ts
@@ -42,9 +42,7 @@ export default class Bold extends Mark {
   }
 
   keys() {
-    return {
-      'Mod-b': () => this.editor.bold(),
-    }
+    return 'Mod-b'
   }
 
   inputRules() {
diff --git a/packages/extension-code/index.ts b/packages/extension-code/index.ts
index f2e2b386f..b93750077 100644
--- a/packages/extension-code/index.ts
+++ b/packages/extension-code/index.ts
@@ -33,9 +33,7 @@ export default class Code extends Mark {
   }
 
   keys() {
-    return {
-      'Mod-`': () => this.editor.code(),
-    }
+    return 'Mod-`'
   }
 
   inputRules() {
diff --git a/packages/extension-italic/index.ts b/packages/extension-italic/index.ts
index 058867fba..4bedfb58d 100644
--- a/packages/extension-italic/index.ts
+++ b/packages/extension-italic/index.ts
@@ -34,9 +34,7 @@ export default class Italic extends Mark {
   }
 
   keys() {
-    return {
-      'Mod-i': () => this.editor.italic(),
-    }
+    return 'Mod-i'
   }
 
   inputRules() {