diff --git a/swh/fuse/fs/entry.py b/swh/fuse/fs/entry.py
--- a/swh/fuse/fs/entry.py
+++ b/swh/fuse/fs/entry.py
@@ -63,6 +63,14 @@
 
         yield None
 
+    async def lookup(self, name: str) -> FuseEntry:
+        """ Look up a FUSE entry by name """
+
+        async for entry in self:
+            if entry.name == name:
+                return entry
+        return None
+
     def get_target(self) -> Union[str, bytes, Path]:
         """ Return the path target of a symlink entry """
 
diff --git a/swh/fuse/fs/mountpoint.py b/swh/fuse/fs/mountpoint.py
--- a/swh/fuse/fs/mountpoint.py
+++ b/swh/fuse/fs/mountpoint.py
@@ -9,7 +9,8 @@
 
 from swh.fuse.fs.artifact import OBJTYPE_GETTERS
 from swh.fuse.fs.entry import EntryMode, FuseEntry
-from swh.model.identifiers import CONTENT, SWHID
+from swh.model.exceptions import ValidationError
+from swh.model.identifiers import CONTENT, SWHID, parse_swhid
 
 
 @dataclass
@@ -33,18 +34,34 @@
     name: str = field(init=False, default="archive")
     mode: int = field(init=False, default=int(EntryMode.RDONLY_DIR))
 
+    def create_child(self, swhid: SWHID) -> FuseEntry:
+        if swhid.object_type == CONTENT:
+            mode = EntryMode.RDONLY_FILE
+        else:
+            mode = EntryMode.RDONLY_DIR
+        return super().create_child(
+            OBJTYPE_GETTERS[swhid.object_type],
+            name=str(swhid),
+            mode=int(mode),
+            swhid=swhid,
+        )
+
     async def __aiter__(self) -> AsyncIterator[FuseEntry]:
         async for swhid in self.fuse.cache.get_cached_swhids():
-            if swhid.object_type == CONTENT:
-                mode = EntryMode.RDONLY_FILE
-            else:
-                mode = EntryMode.RDONLY_DIR
-            yield self.create_child(
-                OBJTYPE_GETTERS[swhid.object_type],
-                name=str(swhid),
-                mode=int(mode),
-                swhid=swhid,
-            )
+            yield self.create_child(swhid)
+
+    async def lookup(self, name: str) -> FuseEntry:
+        entry = await super().lookup(name)
+        if entry:
+            return entry
+
+        # On the fly mounting of a new artifact
+        try:
+            swhid = parse_swhid(name)
+            await self.fuse.get_metadata(swhid)
+            return self.create_child(swhid)
+        except ValidationError:
+            return None
 
 
 @dataclass
diff --git a/swh/fuse/fuse.py b/swh/fuse/fuse.py
--- a/swh/fuse/fuse.py
+++ b/swh/fuse/fuse.py
@@ -184,14 +184,12 @@
 
         name = os.fsdecode(name)
         parent_entry = self.inode2entry(parent_inode)
-
-        async for entry in parent_entry:
-            if name == entry.name:
-                attr = await self.get_attrs(entry)
-                return attr
-
-        logging.error(f"Unknown name during lookup: '{name}'")
-        raise pyfuse3.FUSEError(errno.ENOENT)
+        lookup_entry = await parent_entry.lookup(name)
+        if lookup_entry:
+            return await self.get_attrs(lookup_entry)
+        else:
+            logging.error(f"Unknown name during lookup: '{name}'")
+            raise pyfuse3.FUSEError(errno.ENOENT)
 
     async def readlink(self, inode: int, _ctx: pyfuse3.RequestContext) -> bytes:
         entry = self.inode2entry(inode)