A system comprising one or more computers implements a synthetic sensor service configured to deploy synthetic sensors to an in-vehicle computing device implementing a synthetic sensor orchestration environment for a vehicle. The synthetic sensor orchestration environment determines a placement decision for a new synthetic sensor to be added to the vehicle based on one or more annotations included in a synthetic sensor package for the new synthetic sensor. The synthetic sensor service and respective synthetic sensor orchestration environments implemented in various types of vehicles provide a consistent way to remotely add additional synthetic sensors and/or other functionality to different types of vehicles after the vehicles have already been put in use by respective owners or operators of the vehicles.