Loop helps you close the loop on email introductions. It is added to the CC line (loop@getlooped.cc) on any intro email and after 2-3 weeks it will follow up with each side privately to determine the status or outcome of the connection, including any follow-on intros that were made from one side to the other.Other than actively adding Loop to CC, it is permissionless. It requires no account or external app - running entirely through regular email workflow.Over 90% of the time the same etiquette that sends the connector to BCC after the intro, will do so for Loop as well - so it only has visibility on the first two emails to determine who is the connector, who the sides are, what are their roles and when to emerge with the ask.Aside from the challenge of maximum datapoint extraction with minimal data at hand, it also had to be built with more than a dozen timing, attribution and meaning guardrails so it wont act irreversibly on inferred state.Some examples include out of office messages, personal assistants, weekends/holidays, intros of 3 or more people, replies from the same person with a different email address or emails that are actually not intros at all where it was CC d by accident.I built loop because I do about ~20 intros per month and realized that I rarely hear back on how they are going (e.g. - if a deal is on the table) or what the outcome eventually was. This visibility makes me a better connector and dealmaker, and it puts me top of mind for attribution without me needing to do awkward reach outs.Loop can also be used for intros you receive, so I use it to see who keeps opening doors for me + gather statistics.Stack: Next.js 16 (App Router) + React 19 + TypeScript on Vercel, Postgres (Supabase) via Prisma, Auth.js for login, Resend for inbound + outbound email, and Claude Haiku classifying the incoming mail. Sentry + Vercel Cron as well.