A wrapper around the "cabal configure" command. It saves a hash of the configure arguments, and skips the actual configure if the arguments have not changed, thus shaving a few seconds off of your build time. Has support for hsenv. If you change your package database make sure to run "cabal-fast-configure --clean"

cabal-fast-configure

#!/bin/sh

set -e

if [ ! -f *.cabal ]
then
  echo "You must run this script from the project root directory (where the .cabal file is)"
	exit 2
fi

DIST_DIR=dist
if [ -n "$HSENV_NAME" ]
then
	DIST_DIR="dist_$HSENV_NAME"
fi

if [ "$1" = "--clean" ]
then
	rm -fv -- $DIST_DIR/setup-config.hash.*
	exit 0
fi

configure_args_hash=`echo "$*" | sha256sum | cut -f 1 -d " "`

FINGERPRINT_FILE="$DIST_DIR/setup-config.hash.$configure_args_hash"

if [ ! -f "$FINGERPRINT_FILE" ]
then
	cabal configure $*
	sha256sum $DIST_DIR/setup-config > "$FINGERPRINT_FILE"
else
	if ! sha256sum --quiet --check "$FINGERPRINT_FILE" > /dev/null 2>&1
	then
		cabal configure $*
	fi
fi