openssl not lets encrypt

**Why do you use OpenSSL instead of Let’s Encrypt?**

This is largely a decision that is based on LittleBizzy’s web hosting approach, which requires our clients to be behind Cloudflare. As the fastest DNS resolver in the world, it simply doesn’t make any sense right now NOT to use Cloudflare, especially since its completely free. By using OpenSSL, which is included in Ubuntu Linux, it means easier installation and configuration, and it never expires either. In contrast, Let’s Encrypt is much more complicated to setup and maintain, and their certificates expire constantly after 90 days, meaning your server management software must constantly renew it and manage it. There is really no point in our view to introduce more potential conflicts and failures into SlickStack, when OpenSSL pairs perfectly with Cloudflare’s free SSL network, soon to be the largest SSL provider in the world. By using self-signed certs, SlickStack [ss] also avoids the potential of Man-In-The-Middle attacks, meaning even stronger security. This decision might change in the future, but for now we will only be supporting OpenSSL self-signed certicates and assuming an integration with Cloudflare.

More: https://slickstack.io/features/openssl/