linux file encryption and smtp

I need someone that is skilled in encryption to build a tool for us to be able to encrypt files on the file system to a pki public key and then send them via smtp via an attachment txt file. I should have ui and command line for this and should be able to scheudle it to watch a dir for new files. in the windows world we have file system watch to get instant notifications of file system changes. I prefer this if possible I need a method to give the tool a new public key incase i need to change it ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform encryption, linux