I have ubuntu 20.04 and the first load it doesnt work. 

20:40 [Info] Loading Oxide Core v2.0.4054...
20:40 [Info] Loading extensions...
20:40 [Info] Loaded extension CSharp v2.0.4083 by Oxide Team and Contributors
20:40 [Info] Loaded extension MySql v2.0.3774 by Oxide Team and Contributors
20:40 [Info] Loaded extension Rust v2.0.5925 by Oxide Team and Contributors
20:40 [Info] Loaded extension SQLite v2.0.3804 by Oxide Team and Contributors
20:40 [Info] Unity version: 2019.4.7f1
20:40 [Info] Loaded extension Unity v2.0.3777 by Oxide Team and Contributors
20:40 [Info] Latest compiler MD5: 8ce6d27e7718e3d164766bba8833537a
20:40 [Info] Local compiler MD5: 8ce6d27e7718e3d164766bba8833537a
20:40 [Info] Using Covalence provider for game 'Rust'
20:40 [Info] [Rcon] Server started successfully on port 28016
20:40 [Info] Loading plugins...
20:40 [Info] Loaded plugin Rust v2.0.5925 by Oxide Team and Contributors
20:40 [Info] Loaded plugin Unity v2.0.3777 by Oxide Team and Contributors
20:40 [Info] Added '// Reference: Facepunch.Sqlite' in plugin 'ImageLibrary'
20:40 [Info] Added '// Reference: UnityEngine.UnityWebRequestModule' in plugin 'ImageLibrary'
20:40 [Error] ExType: TypeInitializationException
20:40 [Error] Exception while starting compiler version : (Exception: Magic number is wrong: 542)
at System.TermInfoReader.ReadHeader (System.Byte[] buffer, System.Int32& position) [0x00028] in <fb001e01371b4adca20013e0ac763896>:0
at System.TermInfoReader..ctor (System.String term, System.String filename) [0x0005f] in <fb001e01371b4adca20013e0ac763896>:0
at System.TermInfoDriver..ctor (System.String term) [0x00055] in <fb001e01371b4adca20013e0ac763896>:0
at System.ConsoleDriver.CreateTermInfoDriver (System.String term) [0x00000] in <fb001e01371b4adca20013e0ac763896>:0
at System.ConsoleDriver..cctor () [0x0004d] in <fb001e01371b4adca20013e0ac763896>:0
20:40 [Warning] Compiler may not be set as executable; chmod +x or 0744/0755 required
20:40 [Error] BaseException: (Exception: Magic number is wrong: 542)
at System.TermInfoReader.ReadHeader (System.Byte[] buffer, System.Int32& position) [0x00028] in <fb001e01371b4adca20013e0ac763896>:0
at System.TermInfoReader..ctor (System.String term, System.String filename) [0x0005f] in <fb001e01371b4adca20013e0ac763896>:0
at System.TermInfoDriver..ctor (System.String term) [0x00055] in <fb001e01371b4adca20013e0ac763896>:0
at System.ConsoleDriver.CreateTermInfoDriver (System.String term) [0x00000] in <fb001e01371b4adca20013e0ac763896>:0
at System.ConsoleDriver..cctor () [0x0004d] in <fb001e01371b4adca20013e0ac763896>:0
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started
20:40 [Error] Error while compiling: compiler version couldn't be started