In the list of features which are somewhat custom to their use case, they listed "Disable POSIX advisory locks". Turns out this is available stock right now as

In the list of features which are somewhat custom to their use case, they listed "Disable POSIX advisory locks". Turns out this is available stock right now as the "unix-none" VFS implementation. We're using it in an almost-but-not-quite-POSIX RTOS that happens to be missing advisory locks. See also https://sqlite.org/vfs.html https://sqlite.org/vfs.html