I have a program which when run from the terminal as either the user or as root, can access and write files to the filesystem. However when I run it as a systemd managed service or daemon it cannot. The daemon process is running as root.

What configuration item am I missing to allow daemons / services to write to the filesystem?

I tried running the program in terminal and it works fine whether as the user or as root.

The working directory is set correctly in the service file.

the service starts properly, it just can’t write to the files it is supposed to.