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     appar-0.1.7
Starting     auto-update-0.1.4
Starting     Only-0.1
Starting     base-compat-0.10.5
Building     appar-0.1.7
Building     auto-update-0.1.4
Building     Only-0.1
Building     base-compat-0.10.5
Completed    appar-0.1.7
Starting     base-orphans-0.8
Completed    Only-0.1
Starting     base64-bytestring-1.0.0.2
Completed    auto-update-0.1.4
Starting     blaze-builder-0.4.1.0
Building     base-orphans-0.8
Building     base64-bytestring-1.0.0.2
Building     blaze-builder-0.4.1.0
Completed    base-orphans-0.8
Starting     bsb-http-chunked-0.0.0.4
Building     bsb-http-chunked-0.0.0.4
Completed    base64-bytestring-1.0.0.2
Starting     byteorder-1.0.4
Building     byteorder-1.0.4
Completed    bsb-http-chunked-0.0.0.4
Starting     bytestring-builder-0.10.8.2.0
Completed    blaze-builder-0.4.1.0
Starting     cabal-doctest-1.0.6
Building     bytestring-builder-0.10.8.2.0
Completed    base-compat-0.10.5
Starting     colour-2.3.4
Completed    bytestring-builder-0.10.8.2.0
Starting     data-default-class-0.1.2.0
Building     cabal-doctest-1.0.6
Completed    byteorder-1.0.4
Starting     dlist-0.8.0.5
Building     colour-2.3.4
Building     data-default-class-0.1.2.0
Building     dlist-0.8.0.5
Completed    data-default-class-0.1.2.0
Starting     easy-file-0.2.2
Building     easy-file-0.2.2
Completed    cabal-doctest-1.0.6
Starting     fail-4.9.0.0
Completed    dlist-0.8.0.5
Starting     hashable-1.2.7.0
Building     fail-4.9.0.0
Completed    fail-4.9.0.0
Starting     integer-logarithms-1.0.2.2
Building     hashable-1.2.7.0
Building     integer-logarithms-1.0.2.2
Completed    easy-file-0.2.2
Starting     nats-1.1.2
Building     nats-1.1.2
Completed    nats-1.1.2
Starting     network-2.8.0.0
Completed    integer-logarithms-1.0.2.2
Starting     network-byte-order-0.0.0.0
Building     network-byte-order-0.0.0.0
Completed    colour-2.3.4
Starting     old-locale-1.0.0.7
Completed    hashable-1.2.7.0
Starting     postgresql-libpq-0.9.4.2
Building     old-locale-1.0.0.7
Completed    network-byte-order-0.0.0.0
Starting     primitive-0.6.4.0
Building     primitive-0.6.4.0
Completed    old-locale-1.0.0.7
Starting     random-1.1
Building     network-2.8.0.0
Building     random-1.1
Failed to install postgresql-libpq-0.9.4.2
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/postgresql-libpq-0.9.4.2-HyacS45qPUc33pszxfYdpM.log ):
cabal: Entering directory '/tmp/cabal-tmp-4437/postgresql-libpq-0.9.4.2'
[1 of 1] Compiling Main             ( /tmp/cabal-tmp-4437/postgresql-libpq-0.9.4.2/dist/setup/setup.hs, /tmp/cabal-tmp-4437/postgresql-libpq-0.9.4.2/dist/setup/Main.o )
Linking /tmp/cabal-tmp-4437/postgresql-libpq-0.9.4.2/dist/setup/setup ...
Configuring postgresql-libpq-0.9.4.2...
setup: The program 'pg_config' is required but it could not be found.

cabal: Leaving directory '/tmp/cabal-tmp-4437/postgresql-libpq-0.9.4.2'
Starting     regex-base-0.93.2
Building     regex-base-0.93.2
Completed    random-1.1
Completed    regex-base-0.93.2
Completed    network-2.8.0.0
Completed    primitive-0.6.4.0
cabal: Error: some packages failed to install:
pg-harness-server-0.6.1-DCgucCOXxYN7bJOyKNRBCJ depends on
pg-harness-server-0.6.1 which failed to install.
postgresql-libpq-0.9.4.2-HyacS45qPUc33pszxfYdpM failed during the configure
step. The exception was:
ExitFailure 1
postgresql-simple-0.6-AUYYqF1Ip9i6KjeltQZU0G depends on postgresql-simple-0.6
which failed to install.