diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..f345238
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,5 @@
+test:
+	test/run.sh
+
+.SILENT:
+.PHONY: test
diff --git a/test/assert.sh b/test/assert.sh
new file mode 100644
index 0000000..f3d03d8
--- /dev/null
+++ b/test/assert.sh
@@ -0,0 +1,139 @@
+#!/bin/bash
+# assert.sh 1.0 - bash unit testing framework
+# Copyright (C) 2009, 2010, 2011, 2012 Robert Lehmann
+#
+# http://github.com/lehmannro/assert.sh
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+export DISCOVERONLY=${DISCOVERONLY:-}
+export DEBUG=${DEBUG:-}
+export STOP=${STOP:-}
+export INVARIANT=${INVARIANT:-}
+
+args="$(getopt -n "$0" -l verbose,help,stop,discover,invariant vhxdi $*)" \
+|| exit -1
+for arg in $args; do
+    case "$arg" in
+        -h)
+            echo "$0 [-vxid] [--verbose] [--stop] [--invariant] [--discover]"
+            echo "`sed 's/./ /g' <<< "$0"` [-h] [--help]"
+            exit 0;;
+        --help)
+            cat <<EOF
+Usage: $0 [options]
+Language-agnostic unit tests for subprocesses.
+
+Options:
+  -v, --verbose    generate output for every individual test case
+  -x, --stop       stop running tests after the first failure
+  -i, --invariant  do not measure timings to remain invariant between runs
+  -d, --discover   collect test suites only, do not run any tests
+  -h               show brief usage information and exit
+  --help           show this help message and exit
+EOF
+            exit 0;;
+        -v|--verbose)
+            DEBUG=1;;
+        -x|--stop)
+            STOP=1;;
+        -i|--invariant)
+            INVARIANT=1;;
+        -d|--discover)
+            DISCOVERONLY=1;;
+    esac
+done
+
+printf -v _indent "\n\t" # local format helper
+
+_assert_reset() {
+    tests_ran=0
+    tests_failed=0
+    tests_errors=()
+    tests_starttime="$(date +%s.%N)" # seconds_since_epoch.nanoseconds
+}
+
+assert_end() {
+    # assert_end [suite ..]
+    tests_endtime="$(date +%s.%N)"
+    tests="$tests_ran ${*:+$* }tests"
+    [[ -n "$DISCOVERONLY" ]] && echo "collected $tests." && _assert_reset && return
+    [[ -n "$DEBUG" ]] && echo
+    [[ -z "$INVARIANT" ]] && report_time=" in $(bc \
+        <<< "${tests_endtime%.N} - ${tests_starttime%.N}" \
+        | sed -e 's/\.\([0-9]\{0,3\}\)[0-9]*/.\1/' -e 's/^\./0./')s" \
+        || report_time=
+
+    if [[ "$tests_failed" -eq 0 ]]; then
+        echo "all $tests passed$report_time."
+    else
+        for error in "${tests_errors[@]}"; do echo "$error"; done
+        echo "$tests_failed of $tests failed$report_time."
+    fi
+    tests_failed_previous=$tests_failed
+    _assert_reset
+    return $tests_failed_previous
+}
+
+assert() {
+    # assert <command> <expected stdout> [stdin]
+    (( tests_ran++ ))
+    [[ -n "$DISCOVERONLY" ]] && return
+    # printf required for formatting
+    printf -v expected "x${2:-}" # x required to overwrite older results
+    result="$(eval 2>/dev/null $1 <<< ${3:-})"
+    # Note: $expected is already decorated
+    if [[ "x$result" == "$expected" ]]; then
+        [[ -n "$DEBUG" ]] && echo -n .
+        return
+    fi
+    [[ -n "$DEBUG" ]] && echo -n X
+    result="$(sed -e :a -e '$!N;s/\n/\\n/;ta' <<< "$result")"
+    [[ -z "$result" ]] && result="nothing" || result="\"$result\""
+    [[ -z "$2" ]] && expected="nothing" || expected="\"$2\""
+    failure="expected $expected${_indent}got $result"
+    report="test #$tests_ran \"$1${3:+ <<< $3}\" failed:${_indent}$failure"
+    tests_errors[$tests_failed]="$report"
+    (( tests_failed++ ))
+    if [[ -n "$STOP" ]]; then
+        [[ -n "$DEBUG" ]] && echo
+        echo "$report"
+        exit 1
+    fi
+}
+
+assert_raises() {
+    # assert_raises <command> <expected code> [stdin]
+    (( tests_ran++ ))
+    [[ -n "$DISCOVERONLY" ]] && return
+    (eval $1 <<< ${3:-}) > /dev/null 2>&1
+    status=$?
+    expected=${2:-0}
+    if [[ "$status" -eq "$expected" ]]; then
+        [[ -n "$DEBUG" ]] && echo -n .
+        return
+    fi
+    [[ -n "$DEBUG" ]] && echo -n X
+    failure="program terminated with code $status instead of $expected"
+    report="test #$tests_ran \"$1${3:+ <<< $3}\" failed:${_indent}$failure"
+    tests_errors[$tests_failed]="$report"
+    (( tests_failed++ ))
+    if [[ -n "$STOP" ]]; then
+        [[ -n "$DEBUG" ]] && echo
+        echo "$report"
+        exit 1
+    fi
+}
+
+_assert_reset
diff --git a/test/run.sh b/test/run.sh
new file mode 100755
index 0000000..1988533
--- /dev/null
+++ b/test/run.sh
@@ -0,0 +1,30 @@
+#! /usr/bin/env bash
+
+resolve_link() {
+  $(type -p greadlink readlink | head -1) $1
+}
+
+abs_dirname() {
+  local cwd="$(pwd)"
+  local path="$1"
+
+  while [ -n "$path" ]; do
+    cd "${path%/*}"
+    local name="${path##*/}"
+    path="$(resolve_link "$name" || true)"
+  done
+
+  pwd
+  cd "$cwd"
+}
+
+
+testdir="$(abs_dirname "$0")"
+testfiles="$(find "$testdir" -name "*-test.sh")"
+
+for testfile in $testfiles; do
+  echo "running: ${testfile/#$(dirname "$testdir")\//}"
+  cd "$(dirname "$testfile")"
+  "$testfile"
+  echo ""
+done