Upgrade Umbra
Plan compatible upgrades for the current alpha release.
Overview
The current source release is 1.0.0-alpha. Treat it as a prerelease and read the selected release notes before replacing binaries. Record the version at both endpoints, keep a protected backup of configuration and retain a known working binary. Upgrades should be planned as a client/server pair when wire behavior changes; a fresh website build is not proof that a remote installation has been upgraded.
Details
Version 0.0.8 corrected X25519MLKEM768 share and shared-secret ordering. The earlier reversed format is not supported; both endpoints must be upgraded. The alpha introduces accelerated reusable TLS ciphers, ready-stream mux scheduling, funded startup windows and batched QUIC ingress. New TCP mux sessions use adaptive_mux=true by default and need an upgraded server. Setting adaptive_mux=false explicitly selects legacy mux; business payloads are not automatically replayed or downgraded.
Optional performance table
[performance]
adaptive_mux = true
quic_congestion = "bbr"Verify
Existing identity keys, short IDs and SNI can remain when a release does not require their rotation. mux=false keeps dedicated Vision behavior, and udp_transport remains independent. After upgrading, verify a normal TCP request, UDP if configured, and shutdown/restart behavior. Compare performance only under comparable path and workload conditions. QUIC defaults to Quinn BBR, which is separate from Linux TCP congestion control and does not guarantee a throughput increase.