Skript nie ładuje się

[10:16:51] [Server thread/ERROR]: Error occurred while enabling Skript v2.2-dev26f (Is it up to date?)
java.lang.NoClassDefFoundError: com/google/gson/GsonBuilder
 at ch.njol.skript.util.chat.ChatMessages.<clinit>(ChatMessages.java:136) ~[?:?]
 at ch.njol.skript.Skript.onEnable(Skript.java:204) ~[?:?]
 at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:335) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at org.bukkit.craftbukkit.v1_8_R1.CraftServer.loadPlugin(CraftServer.java:356) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at org.bukkit.craftbukkit.v1_8_R1.CraftServer.enablePlugins(CraftServer.java:316) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at net.minecraft.server.v1_8_R1.MinecraftServer.q(MinecraftServer.java:402) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at net.minecraft.server.v1_8_R1.MinecraftServer.k(MinecraftServer.java:370) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at net.minecraft.server.v1_8_R1.MinecraftServer.a(MinecraftServer.java:325) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at net.minecraft.server.v1_8_R1.DedicatedServer.init(DedicatedServer.java:211) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:505) [spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at java.lang.Thread.run(Unknown Source) [?:1.8.0_131]
Caused by: java.lang.ClassNotFoundException: com.google.gson.GsonBuilder
 at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_131]
 at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:101) ~[spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-1.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-c3c767f-33d5de3]
 at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_131]
 at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_131]
 ... 13 more
[10:16:51] [Server thread/INFO]: Server permissions file permissions.yml is empty, ignoring it