Topic

Smart contract immutability

The practice of permanently giving up the ability to change deployed contract code, usually by revoking an upgrade authority, so users can rely on the code staying as audited.

Current clusters

build1 publisher

A feature gate replaced SPL Token's bytecode beneath its hard-coded address

SIMD-0266 activated at the start of epoch 971 on 13 May 2026, putting p-token behind the classic token program ID on the upgradeable loader with its upgrade authority set to none. Nobody redeployed anything.

Publishers:dev.to

Reality

Evidence62
Adoption88
Hype gap−12
Incentives30
Confidence65

build1 publisher

SIMD-0500 turns the one-instruction program freeze into a three-transaction rebuild

Once the gate is active, Solana's upgradeable loader checks a program's SBPF version before it will set the upgrade authority to none, so pre-v3 builds have to be recompiled and redeployed before they can be frozen.

Publishers:dev.to

Reality

Evidence40
Adoption20
Hype gap+15
Incentives60
Confidence42