diff --git a/lib/utils/entity-text.js b/lib/utils/entity-text.js
--- a/lib/utils/entity-text.js
+++ b/lib/utils/entity-text.js
@@ -91,7 +91,18 @@
   +hex: string,
 };
 
-type EntityTextComponent = UserEntity | ThreadEntity | ColorEntity | string;
+type FarcasterUserEntity = {
+  +type: 'farcaster_user',
+  +fid: string,
+  +farcasterUsername?: ?string,
+};
+
+type EntityTextComponent =
+  | UserEntity
+  | ThreadEntity
+  | ColorEntity
+  | FarcasterUserEntity
+  | string;
 
 export type EntityText = $ReadOnlyArray<EntityTextComponent>;
 
@@ -239,6 +250,12 @@
   hex: input.hex,
 });
 
+type EntityTextFarcasterUserInput = { +fid: string };
+entityTextFunction.fcUser = (input: EntityTextFarcasterUserInput) => ({
+  type: 'farcaster_user',
+  fid: input.fid,
+});
+
 // ET is a JS tag function used in template literals, eg. ET`something`
 // It allows you to compose raw text and "entities" together
 type EntityTextFunction = ((
@@ -248,6 +265,7 @@
   +thread: EntityTextThreadInput => ThreadEntity,
   +user: EntityTextUserInput => UserEntity,
   +color: EntityTextColorInput => ColorEntity,
+  +fcUser: EntityTextFarcasterUserInput => FarcasterUserEntity,
   ...
 };
 const ET: EntityTextFunction = entityTextFunction;
@@ -335,6 +353,10 @@
   return makePossessive({ str, isViewer });
 }
 
+function getNameForFarcasterUserEntity(entity: FarcasterUserEntity): string {
+  return entity.farcasterUsername ?? '<failed to fetch Farcaster username>';
+}
+
 type EntityTextToRawStringParams = {
   +threadID?: ?string,
   +ignoreViewer?: ?boolean,
@@ -355,6 +377,8 @@
       return entity.hex;
     } else if (entity.type === 'user') {
       return getNameForUserEntity(entity, params?.ignoreViewer);
+    } else if (entity.type === 'farcaster_user') {
+      return getNameForFarcasterUserEntity(entity);
     } else {
       invariant(
         false,
@@ -370,13 +394,20 @@
   +renderThread: ({ +id: string, +name: string }) => React.Node,
   +renderUser: ({ +userID: string, +usernameText: string }) => React.Node,
   +renderColor: ({ +hex: string }) => React.Node,
+  +renderFarcasterUser: ({ +farcasterUsername: string }) => React.Node,
 };
 function entityTextToReact(
   entityText: EntityText,
   threadID: string,
   renderFuncs: RenderFunctions,
 ): React.Node {
-  const { renderText, renderThread, renderUser, renderColor } = renderFuncs;
+  const {
+    renderText,
+    renderThread,
+    renderUser,
+    renderColor,
+    renderFarcasterUser,
+  } = renderFuncs;
   // ESLint doesn't recognize that invariant always throws
   // eslint-disable-next-line consistent-return
   return entityText.map((entity, i) => {
@@ -414,6 +445,13 @@
           {renderUser({ userID, usernameText })}
         </React.Fragment>
       );
+    } else if (entity.type === 'farcaster_user') {
+      const name = getNameForFarcasterUserEntity(entity);
+      return (
+        <React.Fragment key={key}>
+          {renderFarcasterUser({ farcasterUsername: name })}
+        </React.Fragment>
+      );
     } else {
       invariant(
         false,
@@ -446,6 +484,7 @@
   | ThreadEntity
   | ColorEntity
   | TextEntity
+  | FarcasterUserEntity
   | ShadowUserEntity;
 function entityTextToObjects(
   entityText: EntityText,
diff --git a/native/chat/inner-robotext-message.react.js b/native/chat/inner-robotext-message.react.js
--- a/native/chat/inner-robotext-message.react.js
+++ b/native/chat/inner-robotext-message.react.js
@@ -77,6 +77,9 @@
         <UserEntity userID={userID} usernameText={usernameText} />
       ),
       renderColor: ({ hex }) => <ColorEntity color={hex} />,
+      renderFarcasterUser: ({ farcasterUsername }) => (
+        <Text>{farcasterUsername}</Text>
+      ),
     });
   }, [resolvedRobotext, activeTheme, threadID, styles.robotext]);
 
diff --git a/web/chat/robotext-message.react.js b/web/chat/robotext-message.react.js
--- a/web/chat/robotext-message.react.js
+++ b/web/chat/robotext-message.react.js
@@ -71,6 +71,9 @@
         <UserEntity userID={userID} usernameText={usernameText} />
       ),
       renderColor: ({ hex }) => <ColorEntity color={hex} />,
+      renderFarcasterUser: ({ farcasterUsername }) => (
+        <span>{farcasterUsername}</span>
+      ),
     });
   }, [resolvedRobotext, threadID]);