Resolving dependencies...
Starting     hashable-1.3.4.0
Starting     th-compat-0.1.3
Starting     primitive-0.7.2.0
Starting     cmdargs-0.10.21
Building     hashable-1.3.4.0
Building     th-compat-0.1.3
Building     cmdargs-0.10.21
Building     primitive-0.7.2.0
Completed    th-compat-0.1.3
Starting     githash-0.1.6.2
Building     githash-0.1.6.2
Completed    hashable-1.3.4.0
Completed    githash-0.1.6.2
Completed    primitive-0.7.2.0
Starting     vector-0.12.3.1
Building     vector-0.12.3.1
Completed    cmdargs-0.10.21
Completed    vector-0.12.3.1
Starting     sv2v-0.0.9
Failed to install sv2v-0.0.9
Build log ( /home/builder/.cabal/logs/ghc-8.10.2/sv2v-0.0.9-JjmZ43355qxAuHEtg4hHgZ.log ):
cabal: Entering directory '/tmp/cabal-tmp-20417/sv2v-0.0.9'
Configuring sv2v-0.0.9...
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-20417/sv2v-0.0.9'
cabal: Error: some packages failed to install:
sv2v-0.0.9-JjmZ43355qxAuHEtg4hHgZ failed during the configure step. The
exception was:
ExitFailure 1