Systems and methods are disclosed herein for editing documents with non-native applications using an application engine. A request to open a document file using a non-native application is received from a user. An engine of the non-native application is selected, the engine being configured to edit the format of the file. Modifications to the document are received by the non-native application engine, and the document is saved to the file using the format of the file, without converting the document to a different format.