Which software should I use?

We default to the latest build of Paper, but you can change it from the Startup section

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We do not recommend using Paper or Spigot in 1.8.8
Here are some updated forks of Paper 1.8.8
· FoxSpigot
· SportPaper
· FlamePaper

· Survival
If you plan to do a Survival, we recommend using latest build of Paper,
or latest build of Purpur(only if you plan to optimize the server)