Anchor 0.31.0
The final major release before Anchor v1 is here!
Anchor 0.31.0 introduces several important changes to enhance performance, compatibility, and usability for Solana developers.
Agave Transition:
With Solana v2.1.0, some binaries are transitioning to a new naming convention under the Agave project. The key change is that Solana’s solana-install utility is now deprecated and being replaced with agave-install.
If your toolchain is configured to use Solana v1.18.19 or later, the new Agave binaries will be automatically installed.
Automatic IDL Conversion:
Anchor 0.31.0 automatically converts old IDLs, so you don’t need to switch versions or run extra commands. The only exception is the anchor idl fetch command, which still requires manual conversion.
Improved Stack Memory Usage:
Stack memory issues have been a major pain point for developers, especially with the try_accounts function where instructions are deserialized, and constraints are checked.
- Optimized init constraints: Previously, init constraints generated a lot of inline code, consuming excessive stack space. Now, this logic runs inside a closure, creating a separate stack frame to significantly reduce memory usage.
- Reliable stack warnings: Before, some stack overflows wouldn't trigger warnings, leading to undefined behavior. Now, Solana v2 with Anchor 0.31.0 ensures reliable stack limit warnings, helping developers catch issues early.
- Improved compatibility with Rust & LLVM changes: Rust compiler updates had increased stack usage, lowering the threshold for stack-related issues and this update counteracts that problem.
Custom Discriminators:
Previously, Anchor enforced fixed 8-byte discriminators for accounts and instructions. While this was fine for most use cases, it wasted bytes in cases where smaller discriminators were sufficient, especially considering Solana’s 1232-byte transaction size limit.
Now, developers can define custom discriminator sizes to save space and optimize for their specific needs.
LazyAccount (Experimental):
LazyAccount is an experimental new account type designed for performance-focused applications that need faster deserialization.
How LazyAccount different from Account<T>:
- Skips unnecessary deserialization: Instead of deserializing the entire account immediately, LazyAccount only loads it when needed, reducing compute costs.
- Best for read-heavy applications: Ideal for programs that frequently fetch accounts but don’t modify them.
This is the final major update before Anchor v1, and streamlines development, enhances performance, and future-proofs Anchor for Solana v2 and beyond.
brimigs