A precompiled form of information derived from CIL metadata is created in a compact type layout (CTL) format. Information in CTL format for each data type in a program can be represented as a contiguous byte stream. Information that is irrelevant to decisions concerning layout of a data type in memory can be suppressed. Information that is irrelevant to creation of virtual machine data structures can be suppressed. The information in CTL format may reference types, methods, and fields by CIL metadata token. Virtual override information such as, for example, a logical virtual table layout, can be pre-computed. Interface implementation information can be pre-computed. A decoder can generate data structures used in generation of an executable from the CTL formatted data.