systemd · medium · solved in-browser (no VM needed) · 3 tiered hints
Write the timer /etc/systemd/system/cache-prune.timer that runs its service 5 minutes after boot and then once an hour thereafter, catching up on missed runs. In [Timer] set OnBootSec=5min, OnUnitActiveSec=1h, and Persistent=true. Add an [Install] section with WantedBy=timers.target. (Authored config, graded structurally — the engine isn't run here.)
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