Peerun is a peer-2-peer Minecraft mod that "just works"
It leverages iroh, allowing you to host/share your Minecraft server/world without setting up any port forwarding or tunneling all traffic via third-party relay servers. Instead, it connects players directly to the server/you, achieving the highest performance (in 90% of cases).
Peerun was mostly inspired by P2P, but solves its problems by using iroh to holepunch and eventually offer a relay which makes it work literary everywhere instantly.
While mods like e4mc, essential or worldhost also exist they mostly rely on centralized servers to relay traffic which is not ideal for latency and throughput.
Mods like modflared on the other hand require you to have a domain, create a cloudflare account and setup DNS entries correctly.
Imagine that you say "connect to that server", iroh will find & maintain the fastest encrypted connection for you, regardless of where it is. Visit Iroh documentation more in-depth explanation. However it's worth noting that Peerun mostly takes what dumbpipe already does and streamlines integration into Minecraft. (You can use dumbpipe alone to achieve mostly the same goal)
If you already have a server set up with proper port forwarding and a static IP address or domain name, then this mod is not for you. But if that's not the case and you just want to enjoy the game with your friends on a server without port forwarding or share your world, then this mod is a perfect choice.
Install the mod on both client and server, start the server, in the server logs you will see 52 character NodeID, copy it share with your friends and just use it like a server address in the game. Or if you want to share your singleplayer world then just open the game to lan, and Peerun will give you the NodeID in the chat to share.
It's a portmanteau created by fusing Perun, the Slavic god of thunder and lightning, with peer, symbolizing the core of decentralized networking - Peerun ⚡