Tracking software usage through the following operations: calculating current digests of common libraries used by software programs and obtaining digital signatures of tracking information of the software programs comprising identifiers of their common libraries and the corresponding current digests; responses are returned to calls for the software programs in association with the corresponding tracking information and digital signatures. A corresponding method under the control of a client comprises receiving a response to a call for a software program in association with the corresponding tracking information and digital signature. The common libraries of the software program are tracked according to a verification of the digital signature and of the current digests against corresponding reference digests. Computer programs and computer program products for performing the methods are proposed. Moreover, corresponding server computing system, client computing system and computing infrastructure are proposed.