Resolving dependencies...
cabal: Could not resolve dependencies:
[__0] trying: ephemeral-0.0.1 (user goal)
[__1] trying: numhask-0.7.1.0 (dependency of ephemeral)
[__2] next goal: box-csv (dependency of ephemeral)
[__2] rejecting: box-csv-0.0.3 (conflict: numhask==0.7.1.0, box-csv =>
numhask>=0.6 && <0.7)
[__2] skipping: box-csv-0.0.2 (has the same characteristics that caused the
previous version to fail: excludes 'numhask' version 0.7.1.0)
[__2] trying: box-csv-0.0.1
[__3] next goal: box (dependency of ephemeral)
[__3] rejecting: box-0.6.3 (conflict: box-csv => box>=0.4 && <0.6)
[__3] skipping: box-0.6.2, box-0.6.1, box-0.6.0 (has the same characteristics
that caused the previous version to fail: excluded by constraint '>=0.4 &&
<0.6' from 'box-csv')
[__3] rejecting: box-0.5.0 (conflict: ephemeral => box>=0.6 && <0.7)
[__3] skipping: box-0.4.0, box-0.3.0, box-0.2.0, box-0.1.0, box-0.0.1.5,
box-0.0.1.4, box-0.0.1.2, box-0.0.1.1 (has the same characteristics that
caused the previous version to fail: excluded by constraint '>=0.6 && <0.7'
from 'ephemeral')
[__3] fail (backjumping, conflict set: box, box-csv, ephemeral)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: ephemeral, numhask, box, box-csv
Try running with --minimize-conflict-set to improve the error message.