Upgrade Authority: From Keypair to Immutable
This is Part 5 of the Solana Program Lifecycle series. In Part 4 we walked through the deploy and upgrade flows: the Buffer account, the chunked writes, and the activation step that copies bytecode into the ProgramData account. Every upgrade instruction checks one thing before it proceeds: who is allowed to do this. That one thing is the upgrade_authority_address field: 33 bytes in the ProgramData account that control who can replace the program’s bytecode. This post traces the full lifecycle of that field, from the keypair that deployed the program to the irreversible --final flag that writes None and freezes the program forever. ...