A daily challenge without a server
The UTC date, corpus version and mode are hashed locally into a deterministic seed. The date labeled “UTC” in the interface is formatted from that same UTC challenge key. This makes today’s configuration repeatable without a runtime request.
Daily challenge date versus practice streak
The shared challenge changes at UTC midnight so everyone receives one global configuration. Your personal practice streak follows your local calendar day instead, which avoids an unexpected streak break around local midnight. Both records stay on this device.
No fake global leaderboard
KeyVelocity does not know how many people played today and does not invent a global rank. The useful comparison is honest: today’s best, your equivalent personal record, a PB Ghost pace marker, or a challenge link shared by a friend.