A software system provides security against unauthorized operations
initiated by software code supplied by an untrusted source. The allowed
operations that are associated with the software code are determined. A
thinned interface is generated which permits the software code to
successfully call only the allowed operations. The software code is
independent of a security environment of the system. The thinned interface
operates in at least one version of the security environment. The software
code and the thinned interface are activated within the system.