The documentation for transmission-daemon-service-type makes it sound like the web interface should be up and running:
Once the service is started, users can interact with the daemon through its Web interface (at ‘http://localhost:9091/’) ... However, the daemon throws 404 when accessing said url: 404: Not Found Couldn't find Transmission's web interface files! Users: to tell Transmission where to look, set the TRANSMISSION_WEB_HOME environment variable to the folder where the web interface's index.html is located. Package Builders: to set a custom default at compile time, #define PACKAGE_DATA_DIR in libtransmission/platform.c or tweak tr_getClutchDir() by hand. Anyone else seeing this? Just for good measure, here is my config: (transmission-daemon-configuration (rpc-authentication-required? #t) (rpc-username "transmission") (rpc-password "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx") (rpc-whitelist-enabled? #t) (rpc-whitelist '("::1" "127.0.0.1" "192.168.*")) (encryption 'require-encrypted-connections) (alt-speed-down (* 1024 1)) ; 1MB/s (alt-speed-up 512) (alt-speed-time-enabled? #t) (alt-speed-time-day 'weekdays) (alt-speed-time-begin (* 60 8)) (alt-speed-time-end (* 60 19)) (watch-dir-enabled? #t) (watch-dir "/var/lib/transmission-daemon/torrents"))