You can open the same SQLite DB from multiple processes and then issue UPDATEs and INSERTs "simultaneously", and SQLite enforces the single-write rule internall

You can open the same SQLite DB from multiple processes and then issue UPDATEs and INSERTs "simultaneously", and SQLite enforces the single-write rule internally with locking - using shared-memory on the same PC or file-locking on NFS-alikes.