Solana network compatibility
September 27 public-cluster observations, Alpenglow on devnet and testnet, and on-chain Clock semantics.
Alpenglow was rechecked 2026-09-27 19:53 UTC through finalized public RPC, with expected genesis, Feature ownership, and activation encoding checks. These are observations, not authenticated ledger proofs or permanent constants.
Alpenglow is active on devnet and testnet in this capture
The feature account A1pengvuM6JEcyNuTnMqepBKhwHE3N6PmUrdATGawhJS reports:
| Cluster | Finalized snapshot slot | Alpenglow gate |
|---|---|---|
| Devnet | 504897120 | Active since 504144000 |
| Testnet | 445830900 | Active since 444620256 |
| Mainnet-beta | 451096445 | Absent |
Anza's feature tracker records testnet epoch 1042 and devnet epoch 1167, with mainnet activation pending. An activation slot is not a measured first Votor-finalized block or a latency benchmark. Validator versions alone do not establish activation.
The pinned SIMD-0326
covers Votor. Rotor, smart sampling, and lazy/asynchronous execution are outside
its scope. Its Review label illustrates why proposal status and deployed
features must be checked separately.
Program implications
Anza's Alpenglow operator guide
preserves Clock's layout and whole-second resolution. During execution,
unix_timestamp estimates when the parent block ended; slot still names the
current slot. Use approximate time or explicit slot deadlines. Do not convert
slots to seconds with a fixed constant or promise subsecond expiry from Clock.
Consensus finality does not remove account locks, compute charges, or application authorization requirements. Hopper byte policies continue to govern tracked mutation inside the program; they do not change the scheduler's account locks.
Other runtime observations from September 27
The same finalized capture checked 22 feature accounts per cluster, with source
keys pinned to Agave f77165963c709934e8ea8564187c00f081b597d1.
| Feature | Devnet | Testnet | Mainnet-beta |
|---|---|---|---|
| 0321 instruction offset, 0339 CPI account limit, 0385 transaction v1 | Active | Active | Active |
| 0449 direct account pointers | Active | Active | Absent |
| 0459 syscall pointer restrictions and sBPF v3 | Active | Active | Active |
| 0460 virtual address adjustments | Active | Active | Unproven: System-owned account |
| Account-data direct mapping and 0512 SHA-512 | Active | Active | Absent |
| 0500 older-sBPF deployment restriction and 0049 remaining-compute syscall | Absent | Absent | Absent |
| 0194 rent threshold and first two 0437 price stages | Active | Active | Active |
| Remaining three 0437 rent stages | Absent | Absent | Absent |
| Slot-time stages through 250 ms | Active | Active | Active |
| 200 ms slot-time stage | Active | Active | Absent |
Keep deployable defaults compatible with the actual target cluster. Query live rent. A devnet test of direct account pointers or SHA-512 does not demonstrate mainnet availability. The reviewed 0558 leader-info syscall remains a proposal, not a shipped Hopper capability.
The release record separates these network observations from Hopper's own compiled and devnet tests. Query the actual target cluster again before enabling a gated feature.
The CPI depth-eight gate was absent in the separate September 25 capture; it was not included in this 22-feature refresh.