1. A method comprising: instantiating a virtual service from a service model, wherein the virtual service is operable to receive requests intended for a particular one of a plurality of software components in a system and generate simulated responses of the particular software component based on a service model modeling responses of the particular software component, wherein the service model is based on monitored requests of the particular software component and monitored responses of the particular software component to the monitored requests; identifying a particular request from another software component intended for the particular software component, wherein the particular request is redirected to the virtual service; generating content of a simulated response to the particular request using the virtual service, wherein the content of the simulated response is in a first language based on the service model, the service model models responses of the particular software component in only a particular set of languages, and the particular set of languages comprises the first language; determining, based on the request, a second language to be applied to the simulated response, wherein the second language is outside the particular set of languages; determining, using a data processing apparatus, a translation of the content from the first language into the second language; and sending a modified version of the simulated response comprising the content in the second language to the other software component in response to the particular request.