Here’s an implementation of lambda calculus (which is TC) at type level in TypeScript: https://github.com/EvolveYourMind/ts-lambda-calc
And here a type-level RegExp matcher: https://github.com/EvolveYourMind/ts-regexp
Another example, SQL-database-in-the-typescript-typesystem here https://github.com/codemix/ts-sql
This would have been much easier if I'd had ts-regexp at the time :)