- Upgrade to Go 1.25.12 and bump critical dependencies (klauspost/compress v1.19.2, golang.org/x/crypto v0.55.0).
- Fix a deadlock in the logger that could occur on close error handling.
- Resolve a JetStream bug where idempotent stream creation could lose data when an offline node catches up from a metalayer snapshot.
Release v2.12.15
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Added Leafnodes support with a configurable dial timeout option for high‑latency links
Decoupled Raft transport and increased disk concurrency (now configurable) with several JetStream performance and memory optimizations;
Decoupled JetStream Raft transport and increased disk concurrency semaphore to 4096 (configurable via max_concurrent_io) to improve performance and memory handling;