diff --git a/src/coreutils/cat.sh b/src/coreutils/cat.sh
new file mode 100644
index 0000000..52c3a93
--- /dev/null
+++ b/src/coreutils/cat.sh
@@ -0,0 +1,97 @@
+#!/bin/bash
+# Bash alternative to external cat call
+#
+# Copyright (C) 2014 Mike Gerwitz
+#
+# This file is part of pkgsh.
+#
+# pkgsh is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see .
+#
+# N.B. While this shell implementation may be faster for most use cases, the
+# external binary will likely be much faster for large streams.
+#
+# This also contains some convenience functions that are not part of
+# GNU coreutils.
+##
+
+[ -z $__PKGSH_INC_COREUTILS_CAT ] || return
+__PKGSH_INC_COREUTILS_CAT=1
+
+
+##
+# Echo characters from stdin up to (but not including) the provided
+# delimiter
+cat-until()
+{
+ local -r delim="${1?Missing terminating delimiter}"
+ local -r file="${2:-/dev/stdin}"
+
+ read -rd "$delim" < "$file"
+ local -ri result=$?
+
+ echo -n "$REPLY"
+ return $result
+}
+
+
+##
+# Echo characters from stdin up to and including the provided delimiter
+cat-until-incl()
+{
+ # `cat-until` will validate
+ local -r delim="$1"
+ cat-until "$@" \
+ && echo -n "$delim"
+}
+
+
+##
+# Proxies to either the shell implementation of cat or the system binary,
+# depending on support
+cat()
+{
+ [[ "$1" =~ ^-[^-\ ] ]] \
+ && command cat "$@" \
+ || quickcat "$@"
+}
+
+
+##
+# Limited implementation of `cat` for performance
+#
+# TODO: The proper research has not yet gone into optimizing this; this is
+# just an initial implementation to get things going. I will be addressing
+# this shortly.
+#
+# TODO: Exit status.
+quickcat()
+{
+ local in="${1:-/dev/stdin}"
+ [ "$in" == - ] && in=/dev/stdin
+ readonly in
+
+ while true; do
+ IFS= read -r || {
+ echo -n "$REPLY"
+ break
+ }
+
+ echo "$REPLY"
+ done < "$in"
+
+ if shift && [ $# -ne 0 ]; then
+ quickcat "$@"
+ fi
+}
+
diff --git a/test/coreutils/test-cat-until.sh b/test/coreutils/test-cat-until.sh
new file mode 100644
index 0000000..c1ce282
--- /dev/null
+++ b/test/coreutils/test-cat-until.sh
@@ -0,0 +1,92 @@
+#!/bin/bash
+# Tests cat-until{,-incl}
+#
+# Copyright (C) 2014 Mike Gerwitz
+#
+# This file is part of pkgsh.
+#
+# pkgsh is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see .
+##
+
+source src/coreutils/cat.sh
+
+
+test-cat-until-no-delim()
+{
+ local result
+ result="$( cat-until X <<< fooXbar )" \
+ || assert -z "non-zero exit"
+
+ assert "$result" == foo
+}
+
+
+test-cat-until-incl-has-delim()
+{
+ local result
+ result="$( cat-until-incl X <<< fooXbar )" \
+ || assert -z "non-zero exit"
+
+ assert "$result" == fooX
+}
+
+
+test-cat-until-from-file()
+{
+ local result
+ result="$( cat-until X <( echo fooXbar ) )" \
+ || assert -z "non-zero exit"
+
+ assert "$result" == foo
+}
+
+
+test-cat-until-incl-from-file()
+{
+ local result
+ result="$( cat-until-incl X <( echo fooXbar ) )" \
+ || assert -z "non-zero exit"
+
+ assert "$result" == fooX
+}
+
+
+test-cat-until-echoes-all-on-no-delim()
+{
+ local result
+ result="$( cat-until X <<< "foobar" )" \
+ && assert -z "returned successfully on missing delim"
+
+ assert $? -eq 1
+ assert "$result" == foobar
+}
+
+
+test-cat-until-incl-echoes-all-on-no-delim-without-trailing-delim()
+{
+ local result
+ result="$( cat-until-incl X <<< "foobar" )" \
+ && assert -z "returned successfully on missing delim"
+
+ assert "$result" == foobar
+}
+
+
+test-cat-until-no-delim
+test-cat-until-incl-has-delim
+test-cat-until-from-file
+test-cat-until-incl-from-file
+test-cat-until-echoes-all-on-no-delim
+test-cat-until-incl-echoes-all-on-no-delim-without-trailing-delim
+
diff --git a/test/coreutils/test-cat.sh b/test/coreutils/test-cat.sh
new file mode 100644
index 0000000..ff443c1
--- /dev/null
+++ b/test/coreutils/test-cat.sh
@@ -0,0 +1,131 @@
+#!/bin/bash
+# Tests bash implementation of cat
+#
+# Copyright (C) 2014 Mike Gerwitz
+#
+# This file is part of pkgsh.
+#
+# pkgsh is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see .
+##
+
+source src/coreutils/cat.sh
+
+set -T
+
+declare -r qcalled=$'\001'
+trap _callset RETURN
+
+_callset()
+{
+ # can't set a var because we're likely in a subshell
+ if [ "${FUNCNAME[1]}" == quickcat ]; then
+ # quickcat recurses
+ if [ "${FUNCNAME[2]}" != quickcat ]; then
+ echo -n "$qcalled"
+ fi
+ fi
+}
+
+_chk()
+{
+ local given="$1" expected="$2"
+
+ [[ "$given" =~ "$qcalled"$ ]] \
+ || assert -z "quickcat not called: $given"
+
+ given="${given%$qcalled}"
+
+ assert "$given" == "$expected"
+}
+
+
+_readall()
+{
+ local -r var="$1"
+ IFS= read -rd '' "$var" || true
+}
+
+
+##
+# Leading and trailing whitespace, be it spaces, newlines, or otherwise,
+# should be retained (something that the shell does not normally like doing)
+test-retains-leading-trailing-whitespace()
+{
+ _readall val < <( echo -e "\n foo \n" )
+ _readall expected < <( command cat <( echo -n "$val" ) )
+ _readall given < <( cat <( echo -n "$val" ) )
+ _chk "$given" "$expected"
+}
+
+
+##
+# If there is no trailing newline, one should not be added
+test-does-not-add-trailing-whitespace()
+{
+ _readall expected < <( command cat <( echo -n foo ) )
+ _readall given < <( cat <( echo -n foo ) )
+ _chk "$given" "$expected"
+}
+
+
+##
+# It is, after all, what `cat` is good at
+test-concatenates-multiple-files()
+{
+ _readall expected < <( command cat <( echo -n foo ) <( echo "Bar" ) )
+ _readall given < <( cat <( echo -n foo ) <( echo "Bar" ) )
+ _chk "$given" "$expected"
+}
+
+
+##
+# As by convention, `-` means `stdin` and can appear anywhere in the file
+# list
+test-can-read-stdin-via-dash()
+{
+ _readall expected < <( command cat <( echo -n foo ) - <<< "Baz" )
+ _readall given < <( cat <( echo -n foo ) - <<< "Baz" )
+ _chk "$given" "$expected"
+}
+
+
+##
+# If no arguments are provided, input is accepted from `stdin`
+test-defaults-to-stdin()
+{
+ _readall expected < <( command cat <<< "foo" )
+ _readall given < <( cat <<< "foo" )
+ _chk "$given" "$expected"
+}
+
+
+##
+# We do not currently handle any options; defer to system binary
+test-any-option-defers-to-binary()
+{
+ _readall given < <( cat -E <<< "foo" )
+
+ # note that this assertion will implicitly ensure that quickcat was not
+ # called; see _callset
+ assert "$given" == 'foo$'$'\n'
+}
+
+
+test-concatenates-multiple-files
+test-can-read-stdin-via-dash
+test-defaults-to-stdin
+test-retains-leading-trailing-whitespace
+test-does-not-add-trailing-whitespace
+test-any-option-defers-to-binary
+