I needed a tool for searching emails and was unhappy with existing solutions. I found out about Meilisearch and realized it would be the perfect engine for emails. So I wrote a tool to index mails (from local Mbox, useful with Thunderbird) and query them in CLI. This is initial release for the tool Meilindex. Search Gui is very simple. I have been using this tool for a couple of months now and I'm very happy with it. Check out Meilisearch for more info on the engine as well!