As shown in the diagram above, a program author creates a program, compiles it to an ELF shared object containing BPF bytecode, and uploads it to the Velas cluster with a special deploy transaction. The cluster makes it available to clients via a program ID. The program ID is an address specified when deploying and is used to reference the program in subsequent transactions.
Upon a successful deployment the account that holds the program is marked executable and its account data become permanently immutable. If any changes are required to the program (features, patches, etc...) the new program must be deployed to a new program ID.
The Velas command line interface supports deploying programs, for more information see the deploy command line usage documentation.