When I wanted this (connectivity by a somewhat low-bandwidth connection), I
solved the problem by running a little local HTTP proxy, solely for opam.
Basically, I ran http-replicator with its cache in my $HOME/tmp directory,
and then set the "http_proxy" environment variable (in the same rc-file
where I sourced opam env)

Worked a treat, and simple to setup.

On Thu, Apr 25, 2019 at 9:55 AM Soegtrop, Michael <
michael.soegtrop@intel.com> wrote:

> Dear Opam Team,
>
>
>
> I am working on scripts to automatically setup a Cygwin MinGW cross based
> development environment for Coq developers on Windows and for testing these
> scripts I have to reinstall Cygwin and opam frequently. I wonder if I could
> spare the downloads by specifying a common download cache folder somewhere
> outside of my Cygwin and .opam folders. Is there an option for this or
> could I e.g. symlink the download folder somewhere or does opam keep and
> index of what is in the download cache folder so that sharing won’t work?
>
>
>
> Best regards,
>
>
>
> Michael
>
> Intel Deutschland GmbH
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