The build is unreachable.

Build log

> /tmp/stackage-build2452$ stack unpack xmlbf-0.4.1@sha256:c0a7e38f611e4090e05debe22fee75e68aa97d59178b3098de3ca7751bf66709
Unpacked xmlbf-0.4.1 to /tmp/stackage-build2452/xmlbf-0.4.1/
> /tmp/stackage-build2452/xmlbf-0.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
[1 of 1] Compiling Main             ( Setup.hs, Setup.o )
Linking Setup ...
> /tmp/stackage-build2452/xmlbf-0.4.1$ ./Setup configure --package-db=clear --package-db=global --package-db=/home/circleci/project/builds/nightly/pkgdb --libdir=/home/circleci/project/builds/nightly/lib --bindir=/home/circleci/project/builds/nightly/bin --datadir=/home/circleci/project/builds/nightly/share --libexecdir=/home/circleci/project/builds/nightly/libexec --sysconfdir=/home/circleci/project/builds/nightly/etc --docdir=/home/circleci/project/builds/nightly/doc/xmlbf-0.4.1 --htmldir=/home/circleci/project/builds/nightly/doc/xmlbf-0.4.1 --haddockdir=/home/circleci/project/builds/nightly/doc/xmlbf-0.4.1
Configuring xmlbf-0.4.1...
> /tmp/stackage-build2452/xmlbf-0.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2452/xmlbf-0.4.1$ ./Setup build
Preprocessing library for xmlbf-0.4.1..
Building library for xmlbf-0.4.1..
[1 of 1] Compiling Xmlbf            ( lib/Xmlbf.hs, dist/build/Xmlbf.o )
> /tmp/stackage-build2452/xmlbf-0.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2452/xmlbf-0.4.1$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181113/xmlbf-0.4.1-H8ZHfmsv8vu7gDCP62oFaT
> /tmp/stackage-build2452/xmlbf-0.4.1$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2452/xmlbf-0.4.1$ ./Setup register
Registering library for xmlbf-0.4.1..