Resolving dependencies...
Starting     primitive-0.7.1.0
Starting     th-compat-0.1.2
Starting     hashable-1.3.2.0
Starting     cmdargs-0.10.21
Building     th-compat-0.1.2
Building     hashable-1.3.2.0
Building     cmdargs-0.10.21
Building     primitive-0.7.1.0
Completed    th-compat-0.1.2
Starting     githash-0.1.6.1
Building     githash-0.1.6.1
Completed    hashable-1.3.2.0
Completed    githash-0.1.6.1
Completed    primitive-0.7.1.0
Starting     vector-0.12.3.0
Building     vector-0.12.3.0
Completed    cmdargs-0.10.21
Completed    vector-0.12.3.0
Downloading  sv2v-0.0.8
Downloaded   sv2v-0.0.8
Starting     sv2v-0.0.8
Failed to install sv2v-0.0.8
Build log ( /home/builder/.cabal/logs/ghc-8.10.2/sv2v-0.0.8-IKKXRYlyPjVA6Ca5nw4R9e.log ):
cabal: Entering directory '/tmp/cabal-tmp-26563/sv2v-0.0.8'
Configuring sv2v-0.0.8...
cabal: The program 'alex' version >=3.2.5 && <4 is required but the version
found at /home/builder/.cabal/bin/alex is version 3.2.4

cabal: Leaving directory '/tmp/cabal-tmp-26563/sv2v-0.0.8'
cabal: Error: some packages failed to install:
sv2v-0.0.8-IKKXRYlyPjVA6Ca5nw4R9e failed during the configure step. The
exception was:
ExitFailure 1