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In recent years, the number of services that are enterprise-grade and don't support custom domains has increased dramatically, and I briefly thought that custom domain support is the order of the day, but I'm going to be a little conservative and say that I think it's still a trust issue for certain organizations to use custom domains. There are services that have come out that mitigate this situation, and for close to a year, this website used a service called cloak.ist to provide custom domains on a limited basis. (The reason it's in the past tense is because we no longer use it, but that's a story for another time.)
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