A method for server-side rendering of native content for presentation within an environment of an application, comprising: receiving, by a data processing system, from a client device (125, 420A-C, 470A-C), a request for content including: a content slot identifier identifying a particular content slot (320A-D) provided by a resource and size information of the requested content; accessing, by the data processing system using the content slot identifier, a database to identify a presentation schema (315A-B) used to arrange content components to generate rendered content files according to a specific configuration for display within an environment of the resource, wherein the presentation schema includes a plurality of style parameters, each of the style parameters including a value matching a value of the resource; identifying, by the data processing system, responsive to the request for content, a content asset including a plurality of content components; rendering, by a content renderer of the data processing system, as a rendered content file, the plurality of content components based on the presentation schema corresponding to the content slot (320A-D); and transmitting, by the data processing system, the rendered content file to the client device for display within the content slot of the resource, wherein the accessing the database comprises using, by a content selection module of the data processing system, a query to identify content assets in a content asset database to retrieve a content asset matching the content slot identifier and the size information included in the request for content, wherein the request for content is an adaptive-sized content request such that the returned rendered content file is configured to fit in variously-sized content slots, and wherein the rendering, by the content renderer of the data processing system, comprises rendering an adaptive content file such that the client device can adjust the adaptive content file by filling in 100% of a width of a content slot with the content file and then sizing a height of the content file to include values of the retrieved content asset. receiving, by a data processing system, from a client device (125, 420A-C, 470A-C), a request for content including: a content slot identifier identifying a particular content slot (320A-D) provided by a resource and size information of the requested content; accessing, by the data processing system using the content slot identifier, a database to identify a presentation schema (315A-B) used to arrange content components to generate rendered content files according to a specific configuration for display within an environment of the resource, wherein the presentation schema includes a plurality of style parameters, each of the style parameters including a value matching a value of the resource; identifying, by the data processing system, responsive to the request for content, a content asset including a plurality of content components; rendering, by a content renderer of the data processing system, as a rendered content file, the plurality of content components based on the presentation schema corresponding to the content slot (320A-D); and transmitting, by the data processing system, the rendered content file to the client device for display within the content slot of the resource, wherein the accessing the database comprises using, by a content selection module of the data processing system, a query to identify content assets in a content asset database to retrieve a content asset matching the content slot identifier and the size information included in the request for content, wherein the request for content is an adaptive-sized content request such that the returned rendered content file is configured to fit in variously-sized content slots, and wherein the rendering, by the content renderer of the data processing system, comprises rendering an adaptive content file such that the client device can adjust the adaptive content file by filling in 100% of a width of a content slot with the content file and then sizing a height of the content file to include values of the retrieved content asset.