There are a couple of open-source sites I work on to help devs find podcast content.

Qit is designed for finding/playing shows by topic, so you can (for example) search for shows about GraphQL: https://qit.cloud/search/graphql

devpodcasts.app lets you browse shows by latest release or by tag: https://devpodcasts.app/shows

Looks like devpodcasts.app is a bit behind though, so I'll write a ticket and get that fixed up soon :)