Preparing for Hopper 0.6
Checked wire contracts, alias-preserving metadata, and explicit client compatibility.
The workspace targets 0.6.0. The published release remains 0.5.0 until the package train completes; use the release status before choosing a dependency. Upgrade the framework, runtime, schema and proc macros together.
Instruction contracts
#[hopper::args] declares checked borrowed fixed layouts. BoundedSlice<'_, T, N>
borrows a bounded sequence of alignment-1 Pod elements directly from instruction
data. Both check nested representations before admitting a handler. Account
authorization and application rules remain the program's responsibility.
Type aliases now preserve scalar widths, fixed-array widths, bounded capacities and string encodings in generated manifests. Opaque aliases are represented as exact-width bytes in clients; the generator does not recover their Rust meaning.
Owned instruction vectors require fixed-width element codecs. Custom TailCodec
implementations must set FIXED_ENCODED_LEN = Some(width) only when every value
encodes to that exact width, equal to MAX_ENCODED_LEN. Variable-length account
tails retain their existing codecs. Nested variable-stride instruction vectors
are rejected because the current manifest cannot describe them faithfully.
Regenerate clients
| Client | Bounded instruction arguments in 0.6 |
|---|---|
| Rust | Checked encoding and decoding; builders return Result; elements are Vec<[u8; WIDTH]> |
| TypeScript | Checked capacities and element byte widths; named byte elements use Uint8Array |
| Python | Checked encoding; vector elements are list[bytes]; string capacities count UTF-8 bytes |
| C, Go, Kotlin | Explicit unsupported-encoding failure before constructing instruction data |
Rust builders for fixed-only instructions keep their signatures. For dynamic
instructions, *_DATA_LEN is the maximum footprint, not the length of every
encoded payload. Handle encoding errors before signing or submitting a transaction.
Python builders also reject fixed byte arguments of the wrong length instead
of silently truncating or padding them.
Runtime behavior
Runtime hashes share the native boundary and its 20,000-slice ABI limit. This is an interface ceiling, not a guarantee that a transaction has enough memory or compute for that many slices. Epoch arithmetic saturates overflow and guards zero epoch lengths. Modular exponentiation checks operand shapes before calling the syscall. Generated raw entrypoints and receipt logging also gain SBF fixes.
Consult the network baseline before enabling optional syscalls. Recorded BLAKE3 failures, unavailable modular exponentiation and the EpochSchedule discrepancy remain distinct from successful fixture execution.
Verification scope
The release dossier records outstanding checks and the exact evidence selected for the working source. Building every program does not execute every handler or feature combination. Internal checks and devnet receipts do not constitute an independent review.