diff --git a/tests/compat.sh b/tests/compat.sh
index a863cc17594a..5dd5f9e0fb98 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -30,6 +30,11 @@ set -u
 # where it may output seemingly unlimited length error logs.
 ulimit -f 20971520
 
+ORIGINAL_PWD=$PWD
+if ! cd "$(dirname "$0")"; then
+    exit 125
+fi
+
 # initialise counters
 TESTS=0
 FAILED=0
@@ -77,6 +82,17 @@ else
     PEER_GNUTLS=""
 fi
 
+guess_config_name() {
+    if git diff --quiet ../include/mbedtls/mbedtls_config.h 2>/dev/null; then
+        echo "default"
+    else
+        echo "unknown"
+    fi
+}
+: ${MBEDTLS_TEST_OUTCOME_FILE=}
+: ${MBEDTLS_TEST_CONFIGURATION:="$(guess_config_name)"}
+: ${MBEDTLS_TEST_PLATFORM:="$(uname -s | tr -c \\n0-9A-Za-z _)-$(uname -m | tr -c \\n0-9A-Za-z _)"}
+
 # default values for options
 # /!\ keep this synchronised with:
 # - basic-build-test.sh
@@ -110,6 +126,8 @@ print_usage() {
     printf "            \tAlso available: GnuTLS (needs v3.2.15 or higher)\n"
     printf "  -M|--memcheck\tCheck memory leaks and errors.\n"
     printf "  -v|--verbose\tSet verbose output.\n"
+    printf "     --outcome-file\tFile where test outcomes are written\n"
+    printf "                   \t(default: \$MBEDTLS_TEST_OUTCOME_FILE, none if empty)\n"
 }
 
 get_options() {
@@ -139,6 +157,9 @@ get_options() {
             -M|--memcheck)
                 MEMCHECK=1
                 ;;
+            --outcome-file)
+                shift; MBEDTLS_TEST_OUTCOME_FILE=$1
+                ;;
             -h|--help)
                 print_usage
                 exit 0
@@ -790,12 +811,29 @@ wait_client_done() {
     echo "EXIT: $EXIT" >> $CLI_OUT
 }
 
+# record_outcome <outcome> [<failure-reason>]
+record_outcome() {
+    echo "$1"
+    if [ -n "$MBEDTLS_TEST_OUTCOME_FILE" ]; then
+        # The test outcome file has the format (in single line):
+        # platform;configuration;
+        # test suite name;test case description;
+        # PASS/FAIL/SKIP;[failure cause]
+        printf '%s;%s;%s;%s;%s;%s\n'                                    \
+            "$MBEDTLS_TEST_PLATFORM" "$MBEDTLS_TEST_CONFIGURATION"      \
+            "compat" "$TITLE"                                           \
+            "$1" "${2-}"                                                \
+            >> "$MBEDTLS_TEST_OUTCOME_FILE"
+    fi
+}
+
 # display additional information if test case fails
 report_fail() {
-    echo "FAIL"
+    FAIL_PROMPT="outputs saved to c-srv-${TESTS}.log, c-cli-${TESTS}.log"
+    record_outcome "FAIL" "$FAIL_PROMPT"
     cp $SRV_OUT c-srv-${TESTS}.log
     cp $CLI_OUT c-cli-${TESTS}.log
-    echo "  ! outputs saved to c-srv-${TESTS}.log, c-cli-${TESTS}.log"
+    echo "  ! $FAIL_PROMPT"
 
     if [ "${LOG_FAILURE_ON_STDOUT:-0}" != 0 ]; then
         echo "  ! server output:"
@@ -818,7 +856,7 @@ run_client() {
     # should we skip?
     if [ "X$SKIP_NEXT" = "XYES" ]; then
         SKIP_NEXT="NO"
-        echo "SKIP"
+        record_outcome "SKIP"
         SKIPPED=$(( $SKIPPED + 1 ))
         return
     fi
@@ -912,10 +950,10 @@ run_client() {
     # report and count result
     case $RESULT in
         "0")
-            echo PASS
+            record_outcome "PASS"
             ;;
         "1")
-            echo SKIP
+            record_outcome "SKIP"
             SKIPPED=$(( $SKIPPED + 1 ))
             ;;
         "2")
@@ -931,13 +969,16 @@ run_client() {
 # MAIN
 #
 
-if cd $( dirname $0 ); then :; else
-    echo "cd $( dirname $0 ) failed" >&2
-    exit 1
-fi
-
 get_options "$@"
 
+# Make the outcome file path relative to the original directory, not
+# to .../tests
+case "$MBEDTLS_TEST_OUTCOME_FILE" in
+    [!/]*)
+        MBEDTLS_TEST_OUTCOME_FILE="$ORIGINAL_PWD/$MBEDTLS_TEST_OUTCOME_FILE"
+        ;;
+esac
+
 # sanity checks, avoid an avalanche of errors
 if [ ! -x "$M_SRV" ]; then
     echo "Command '$M_SRV' is not an executable file" >&2