I tried to install/build git-monitor on ubuntu18.04 - and failed :-(

[xsteve]

Here is what I tried:
apt-install cabal-install
cabal update
cabal install git-monitor

It started quite good by downloading lots of needed packages.
But finally it failed with the following error messages:

Resolving dependencies...
Configuring git-monitor-3.1.1.5...
Building git-monitor-3.1.1.5...
Failed to install git-monitor-3.1.1.5
Build log ( /home/stefan/.cabal/logs/git-monitor-3.1.1.5.log ):
cabal: Entering directory '/tmp/cabal-tmp-9812/git-monitor-3.1.1.5'
Configuring git-monitor-3.1.1.5...
Building git-monitor-3.1.1.5...
Preprocessing executable 'git-monitor' for git-monitor-3.1.1.5...
[1 of 1] Compiling Main             ( Main.hs, dist/build/git-monitor/git-monitor-tmp/Main.o )

Main.hs:53:27: error:
    • Variable not in scope: (<>) :: Mod f2 a10 -> Mod f1 a9 -> t3
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:53:43: error:
    • Variable not in scope:
        (<>) :: t3 -> Mod f0 a8 -> Mod FlagFields Bool
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:54:27: error:
    • Variable not in scope: (<>) :: Mod f5 a13 -> Mod f4 a12 -> t4
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:54:45: error:
    • Variable not in scope:
        (<>) :: t4 -> Mod f3 a11 -> Mod FlagFields Bool
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:55:27: error:
    • Variable not in scope: (<>) :: Mod f8 a16 -> Mod f7 a15 -> t5
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:55:43: error:
    • Variable not in scope:
        (<>) :: t5 -> Mod f6 a14 -> Mod FlagFields Bool
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:57:25: error:
    • Variable not in scope:
        (<>) :: Mod f11 a18 -> Mod f10 [Char] -> t6
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:58:10: error:
    • Variable not in scope:
        (<>) :: t6 -> Mod f9 a17 -> Mod OptionFields FilePath
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:59:30: error:
    • Variable not in scope: (<>) :: Mod f15 a21 -> Mod f14 a20 -> t8
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:59:49: error:
    • Variable not in scope: (<>) :: t8 -> Mod f13 [Char] -> t7
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:60:20: error:
    • Variable not in scope:
        (<>) :: t7 -> Mod f12 a19 -> Mod OptionFields FilePath
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:61:32: error:
    • Variable not in scope: (<>) :: Mod f19 a24 -> Mod f18 a23 -> t10
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:61:51: error:
    • Variable not in scope: (<>) :: t10 -> Mod f17 Integer -> t9
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:62:17: error:
    • Variable not in scope:
        (<>) :: t9 -> Mod f16 a22 -> Mod OptionFields Int
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:63:27: error:
    • Variable not in scope: (<>) :: Mod f22 a27 -> Mod f21 a26 -> t11
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:64:17: error:
    • Variable not in scope:
        (<>) :: t11 -> Mod f20 a25 -> Mod FlagFields Bool
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:70:27: error:
    • Variable not in scope: (<>) :: InfoMod a30 -> InfoMod a29 -> t12
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:70:44: error:
    • Variable not in scope:
        (<>) :: t12 -> InfoMod a28 -> InfoMod Options
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:105:43: error:
    • Variable not in scope:
        (<>)
          :: m6 ()
             -> RefName -> Control.Monad.Trans.Reader.ReaderT LgRepo IO a5
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:106:50: error:
    • Variable not in scope:
        (<>)
          :: m7 ()
             -> T.Text -> Control.Monad.Trans.Reader.ReaderT LgRepo IO a6
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:107:58: error:
    • Variable not in scope:
        (<>)
          :: m8 ()
             -> RefName -> Control.Monad.Trans.Reader.ReaderT LgRepo IO a7
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:114:38: error:
    • Variable not in scope: (<>) :: [Char] -> T.Text -> RefName
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:183:39: error:
    • Variable not in scope:
        (<>) :: t0 m4 () -> T.Text -> TreeT LgRepo m a4
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:194:49: error:
    • Variable not in scope: (<>) :: t2 m5 () -> RefName -> t1
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:194:59: error:
    • Variable not in scope: (<>) :: t1 -> [Char] -> TreeT LgRepo m ()
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:205:32: error:
    • Variable not in scope:
        (<>) :: m3 () -> T.Text -> TreeT LgRepo m9 a3
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:217:46: error:
    • Variable not in scope:
        (<>) :: m0 () -> T.Text -> TreeT LgRepo m9 a0
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:221:40: error:
    • Variable not in scope:
        (<>) :: m1 () -> T.Text -> TreeT LgRepo m9 a1
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)

Main.hs:224:40: error:
    • Variable not in scope:
        (<>) :: m2 () -> T.Text -> TreeT LgRepo m9 a2
    • Perhaps you meant one of these:
        ‘<$>’ (imported from Prelude), ‘<*>’ (imported from Prelude),
        ‘>>’ (imported from Prelude)
cabal: Leaving directory '/tmp/cabal-tmp-9812/git-monitor-3.1.1.5'

[xsteve]

To follow up my installation attempt.
I found out, how to compile the sources from git.
I did the following and got a working git-monitor executable:

 # git clone https://github.com/jwiegley/gitlib
 # cd gitlib/git-monitor
 # runhaskell Setup.hs configure --user
 # runhaskell Setup.hs build
   -> Generates dist/build/git-monitor/git-monitor

However, it would be nice to have a working "cabal install git-monitor" as well.

[jwiegley]

It sounds like the lower-bounds for git-monitor need to be increased, since what's on Hackage should build given a clean ~/.cabal.