Nothing
The SWI-Prolog software and its official installers do not collect, store, or transmit any personal data or telemetry. No information about the user, the host system, or program execution is sent to the project or to any third party.
User-installed Prolog code or third-party packages may have their own networking behaviour; this policy covers only the binaries distributed by the SWI-Prolog project.
The project website (https://www.swi-prolog.org) keeps standard web server access logs for operational purposes.
Any scripts or data that you put into this service are public.
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