diff --git a/src/mol-data/structure/symmetry.ts b/src/mol-data/query.ts
similarity index 100%
rename from src/mol-data/structure/symmetry.ts
rename to src/mol-data/query.ts
diff --git a/src/mol-data/selection.ts b/src/mol-data/selection.ts
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..8ab8a8794032b81dc8914ce08e7423b1681de701 100644
--- a/src/mol-data/selection.ts
+++ b/src/mol-data/selection.ts
@@ -0,0 +1,9 @@
+/**
+ * Copyright (c) 2017 molio contributors, licensed under MIT, See LICENSE file for more info.
+ *
+ * @author David Sehnal <david.sehnal@gmail.com>
+ */
+
+import Structure from './structure'
+
+export type Selection = Structure | Structure[]
\ No newline at end of file
diff --git a/src/mol-data/structure.ts b/src/mol-data/structure.ts
index e7ae5aa15d03b66e264c6268c8cde3a713a39af1..b8dcf367c6c06f9e8dbd60bf1cd9f964b2b46382 100644
--- a/src/mol-data/structure.ts
+++ b/src/mol-data/structure.ts
@@ -47,9 +47,8 @@ export interface Structure { units: { [id: number]: Unit }, atoms: AtomSet }
 
 export namespace Structure {
     export const Empty: Structure = { units: {}, atoms: AtomSet.Empty };
-
-    export enum Algebra { AddUnit, RemoveUnit, UpdateConformation /* specify which units map to which */ }
 }
 
+export default Structure
 // export interface Selection { structure: Structure, sets: AtomSet[] }
 // type SelectionImpl = Structure | Structure[]
\ No newline at end of file
diff --git a/src/mol-data/structure/selectors.ts b/src/mol-data/structure/selectors.ts
deleted file mode 100644
index c8e599b3a9cc85b6e82d4dbf25affd5bb55ae482..0000000000000000000000000000000000000000
--- a/src/mol-data/structure/selectors.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-/**
- * Copyright (c) 2017 molio contributors, licensed under MIT, See LICENSE file for more info.
- *
- * @author David Sehnal <david.sehnal@gmail.com>
- */
-
-import { Selector } from './model'
-
-const set = {};
-
-export type Selectors = Selector.Set<typeof set>
\ No newline at end of file
diff --git a/src/mol-data/structure/structure.ts b/src/mol-data/structure/structure.ts
deleted file mode 100644
index d13a9ee15253efdf6c8bbb040a46ad70e37e99eb..0000000000000000000000000000000000000000
--- a/src/mol-data/structure/structure.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-/**
- * Copyright (c) 2017 molio contributors, licensed under MIT, See LICENSE file for more info.
- *
- * @author David Sehnal <david.sehnal@gmail.com>
- */
-