The build is unreachable.

Build log

> /tmp/stackage-build2451$ stack unpack hsexif-0.6.1.6@sha256:8972d2c8f81734c3acd1a269f74b153a865b1898c58eed561cb74cd0ab7eecb5
Unpacked hsexif-0.6.1.6 to /tmp/stackage-build2451/hsexif-0.6.1.6/
> /tmp/stackage-build2451/hsexif-0.6.1.6$ 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-build2451/hsexif-0.6.1.6$ ./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/hsexif-0.6.1.6 --htmldir=/home/circleci/project/builds/nightly/doc/hsexif-0.6.1.6 --haddockdir=/home/circleci/project/builds/nightly/doc/hsexif-0.6.1.6
Configuring hsexif-0.6.1.6...
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ./Setup build
Preprocessing library for hsexif-0.6.1.6..
Building library for hsexif-0.6.1.6..
[1 of 5] Compiling Graphics.Helpers ( Graphics/Helpers.hs, dist/build/Graphics/Helpers.o )
[2 of 5] Compiling Graphics.Types   ( Graphics/Types.hs, dist/build/Graphics/Types.o )
[3 of 5] Compiling Graphics.PrettyPrinters ( Graphics/PrettyPrinters.hs, dist/build/Graphics/PrettyPrinters.o )
[4 of 5] Compiling Graphics.ExifTags ( Graphics/ExifTags.hs, dist/build/Graphics/ExifTags.o )
[5 of 5] Compiling Graphics.HsExif  ( Graphics/HsExif.hs, dist/build/Graphics/HsExif.o )
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ./Setup copy
Installing library in /home/circleci/project/builds/nightly/lib/x86_64-linux-ghc-8.7.20181121/hsexif-0.6.1.6-IRY2MbA0s04KTsPzR926iN
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ghc -clear-package-db -global-package-db -package-db=/home/circleci/project/builds/nightly/pkgdb Setup
> /tmp/stackage-build2451/hsexif-0.6.1.6$ ./Setup register
Registering library for hsexif-0.6.1.6..