"Badly". At least once a week someone managed to overwrite a change another client had just made. When I left, they were running a cron to copy it every minute as a "quick restore" when it happened.
maybe there is an email thread shared between all clients for acquiring / releasing the write lock on the xml file
Semaphore as a service Slack Chat bot.
Seen that.
Shared drive with excel files, people would shout at each other to 'release the lock'
Yeah, first real job had the customer database as a VB frontend onto an Access file shared over {whatever Win95 was using in 1996-97}. After a few snafus, the CS / Sales people learned that they had to single-task with the database.