Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
default in the next version of cabal-install. Please file a bug if you cannot
replicate a working v1- use case with the new-style commands.

For more information, see: https://wiki.haskell.org/Cabal/NewBuild

Resolving dependencies...
Starting     hashable-1.3.0.0
Starting     parser-combinators-1.2.0
Starting     integer-logarithms-1.0.3
Starting     primitive-0.7.0.0
Building     parser-combinators-1.2.0
Building     integer-logarithms-1.0.3
Building     hashable-1.3.0.0
Building     primitive-0.7.0.0
Completed    integer-logarithms-1.0.3
Completed    parser-combinators-1.2.0
Completed    hashable-1.3.0.0
Starting     case-insensitive-1.2.1.0
Starting     unordered-containers-0.2.10.0
Building     case-insensitive-1.2.1.0
Building     unordered-containers-0.2.10.0
Completed    case-insensitive-1.2.1.0
Completed    primitive-0.7.0.0
Starting     scientific-0.3.6.2
Building     scientific-0.3.6.2
Completed    unordered-containers-0.2.10.0
Completed    scientific-0.3.6.2
Starting     megaparsec-7.0.5
Building     megaparsec-7.0.5
Completed    megaparsec-7.0.5
Starting     tomland-1.2.0.0
Building     tomland-1.2.0.0
Failed to install tomland-1.2.0.0
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/tomland-1.2.0.0-ActAGvEWYvzH3tfl86Z3UI.log ):
cabal: Entering directory '/tmp/cabal-tmp-13507/tomland-1.2.0.0'
Configuring tomland-1.2.0.0...
Preprocessing library for tomland-1.2.0.0..
Building library for tomland-1.2.0.0..
[ 1 of 22] Compiling Toml.Bi.Monad
[ 2 of 22] Compiling Toml.Parser.Core
[ 3 of 22] Compiling Toml.Parser.String
[ 4 of 22] Compiling Toml.PrefixTree
[ 5 of 22] Compiling Toml.Parser.Key
[ 6 of 22] Compiling Toml.Type.Value
[ 7 of 22] Compiling Toml.Type.AnyValue
[ 8 of 22] Compiling Toml.Type.UValue
[ 9 of 22] Compiling Toml.Type.TOML
[10 of 22] Compiling Toml.Type
[11 of 22] Compiling Toml.Printer
[12 of 22] Compiling Toml.Parser.Value
[13 of 22] Compiling Toml.Parser.Item
[14 of 22] Compiling Toml.Parser.Validate
[15 of 22] Compiling Toml.Parser
[16 of 22] Compiling Toml.Edsl
[17 of 22] Compiling Toml.Bi.Map
[18 of 22] Compiling Toml.Bi.Code
[19 of 22] Compiling Toml.Bi.Combinators
[20 of 22] Compiling Toml.Bi
[21 of 22] Compiling Toml.Generic
[22 of 22] Compiling Toml
Preprocessing executable 'play-tomland' for tomland-1.2.0.0..
Building executable 'play-tomland' for tomland-1.2.0.0..
[1 of 1] Compiling Main
Linking dist/build/play-tomland/play-tomland ...
Preprocessing executable 'readme' for tomland-1.2.0.0..
Building executable 'readme' for tomland-1.2.0.0..
ghc: could not execute: markdown-unlit
cabal: Leaving directory '/tmp/cabal-tmp-13507/tomland-1.2.0.0'
cabal: Error: some packages failed to install:
tomland-1.2.0.0-ActAGvEWYvzH3tfl86Z3UI failed during the building phase. The
exception was:
ExitFailure 1