diff --git a/src/libsysprof-analyze/sysprof-mount-namespace-private.h b/src/libsysprof-analyze/sysprof-mount-namespace-private.h
index 28b110d9..4f4ecd26 100644
--- a/src/libsysprof-analyze/sysprof-mount-namespace-private.h
+++ b/src/libsysprof-analyze/sysprof-mount-namespace-private.h
@@ -39,7 +39,5 @@ void                    sysprof_mount_namespace_add_mount   (SysprofMountNamespa
                                                              SysprofMount          *mount);
 char                  **sysprof_mount_namespace_translate   (SysprofMountNamespace *self,
                                                              const char            *path);
-GMappedFile            *sysprof_mount_namespace_open        (SysprofMountNamespace *self,
-                                                             const char            *path);
 
 G_END_DECLS
diff --git a/src/libsysprof-analyze/sysprof-mount-namespace.c b/src/libsysprof-analyze/sysprof-mount-namespace.c
index c096aebf..8e556d39 100644
--- a/src/libsysprof-analyze/sysprof-mount-namespace.c
+++ b/src/libsysprof-analyze/sysprof-mount-namespace.c
@@ -146,3 +146,30 @@ sysprof_mount_namespace_add_mount (SysprofMountNamespace *self,
 
   g_ptr_array_add (self->mounts, mount);
 }
+
+/**
+ * sysprof_mount_namespace_translate:
+ * @self: a #SysprofMountNamespace
+ * @file: the path within the mount namespace to translate
+ *
+ * Attempts to translate a path within the mount namespace into a
+ * path available in our current mount namespace.
+ *
+ * As overlays are involved, multiple paths may be returned which
+ * could contain the target file. You should check these starting
+ * from the first element in the resulting array to the last.
+ *
+ * Returns: (transfer full) (nullable): a UTF-8 encoded string array
+ *   if successful; otherwise %NULL and @error is set.
+ */
+char **
+sysprof_mount_namespace_translate (SysprofMountNamespace *self,
+                                   const char            *file)
+{
+  g_return_val_if_fail (SYSPROF_IS_MOUNT_NAMESPACE (self), NULL);
+  g_return_val_if_fail (file != NULL, NULL);
+
+  /* TODO: */
+
+  return NULL;
+}