diff --git a/benchmarks/.gitignore b/benchmarks/.gitignore
new file mode 100644
index 00000000..fbca2253
--- /dev/null
+++ b/benchmarks/.gitignore
@@ -0,0 +1 @@
+results/
diff --git a/benchmarks/benchmark.sh b/benchmarks/benchmark.sh
old mode 100644
new mode 100755
index 9f1a7a28..05711b44
--- a/benchmarks/benchmark.sh
+++ b/benchmarks/benchmark.sh
@@ -1,9 +1,9 @@
 #!/bin/sh
 
-RESULTS="results"
+RESULTS=${1:-"results"}
 LOGFILE=benchmarks.log
 
-function print_log() {
+print_log() {
 
 	local message=$1
 
@@ -11,7 +11,7 @@ function print_log() {
 
 }
 
-mkdir -p $RESULTS
+mkdir -p "$RESULTS"
 # rm $RESULTS/$LOGFILE || true
 
 echo "==> verifying datalog programs";
@@ -20,5 +20,5 @@ print_log "==> verifying datalog programs";
 # bash putbxdebug.sh $RESULTS
 # bash putbxdebug.inc.sh $RESULTS
 
-bash putbx.sh $RESULTS
-bash putbx.inc.sh $RESULTS
+bash putbx.sh "$RESULTS"
+bash putbx.inc.sh "$RESULTS"
diff --git a/benchmarks/compare_results.sh b/benchmarks/compare_results.sh
new file mode 100755
index 00000000..f304901a
--- /dev/null
+++ b/benchmarks/compare_results.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+# $ ./compare_results.sh <DIR1> <DIR2> list
+# $ ./compare_results.sh <DIR1> <DIR2> check <REL-PATH> [<DIFF-CMD>]
+# $ ./compare_results.sh <DIR1> <DIR2> check_all
+
+if [ $# -lt 2 ]; then
+    echo "invalid number of arguments"
+fi
+LEFT=$1
+RIGHT=$2
+CMD=${3:-check_all}
+
+case $CMD in
+    list)
+        echo "$LEFT:"
+        for FILE in $(ls "$LEFT"/gensql/*/*.sql); do
+            RELPATH="${FILE##"$LEFT/"}"
+            echo "* $RELPATH"
+        done
+        ;;
+    check)
+        RELPATH=$4
+        DIFF=${5:-diff}
+        echo "Compare $LEFT and $RIGHT"
+        echo "=======<$RELPATH>======="
+        "$DIFF" "$LEFT/$RELPATH" "$RIGHT/$RELPATH"
+        ;;
+    check_all)
+        DIFF=${5:-diff}
+        echo "Compare $LEFT and $RIGHT"
+        for FILE in $(ls "$LEFT"/gensql/*/*.sql); do
+            RELPATH="${FILE##"$LEFT/"}"
+            echo "=======<$RELPATH>======="
+            "$DIFF" "$LEFT/$RELPATH" "$RIGHT/$RELPATH"
+        done
+        ;;
+    *)
+        echo "invalid command ($CMD)"
+        ;;
+esac
diff --git a/benchmarks/putbx.sh b/benchmarks/putbx.sh
index 19e5fe1e..78e03207 100644
--- a/benchmarks/putbx.sh
+++ b/benchmarks/putbx.sh
@@ -21,6 +21,7 @@ function print_log() {
 
 mkdir -p $RESULTS
 mkdir -p $RESULTS/gensql
+mkdir -p $RESULTS/genlean
 mkdir -p $RESULTS/compile
 
 # rm $RESULTS/$LOGFILE || true
@@ -28,11 +29,11 @@ mkdir -p $RESULTS/compile
 
 for FILE in $(cat dl_list)
 do
-    print_log "==> running on $FILE.dl" 
-    echo "==> running on $FILE.dl" 
+    print_log "==> running on $FILE.dl"
+    echo "==> running on $FILE.dl"
     mkdir -p $RESULTS/compile/$FILE
     mkdir -p $RESULTS/gensql/$FILE
-    /usr/bin/time -a -f "$FILE , %e" -o $RESULTS/$RESULTSFILE birds -f $FILE.dl -o $RESULTS/gensql/$FILE.sql -v -u > $RESULTS/compile/$FILE.log 2>> $RESULTS/compile/$FILE.err
+    mkdir -p $RESULTS/genlean/$FILE
+    /usr/bin/time -a -f "$FILE , %e" -o $RESULTS/$RESULTSFILE birds -f $FILE.dl -o $RESULTS/gensql/$FILE.sql -v -u -l $RESULTS/genlean/$FILE.lean > $RESULTS/compile/$FILE.log 2>> $RESULTS/compile/$FILE.err
     sleep 10
 done
-
diff --git a/benchmarks/see_results.sh b/benchmarks/see_results.sh
new file mode 100755
index 00000000..d239a869
--- /dev/null
+++ b/benchmarks/see_results.sh
@@ -0,0 +1,50 @@
+#!/bin/sh
+
+# $ ./see_results.sh see_log <DIR>
+# $ ./see_results.sh see_err <DIR>
+# $ ./see_results.sh diff_log <DIR1> <DIR2>
+# $ ./see_results.sh diff_err <DIR1> <DIR2>
+
+if [ $# -lt 2 ]; then
+    echo "invalid number of arguments"
+fi
+
+CMD=$1
+
+case $CMD in
+    see_log)
+        DIR=$2
+        for FILE in "$DIR"/compile/*/*.log; do
+            echo "=======<$FILE>======="
+            cat "$FILE"
+        done
+        ;;
+    see_err)
+        DIR=$2
+        for FILE in "$DIR"/compile/*/*.err; do
+            echo "=======<$FILE>======="
+            cat "$FILE"
+        done
+        ;;
+    diff_log)
+        LEFT=$2
+        RIGHT=$3
+        for FILE in "$LEFT"/compile/*/*.log; do
+            RELPATH="${FILE##"$LEFT/"}"
+            echo "=======<$RELPATH>======="
+            diff -u "$LEFT/$RELPATH" "$RIGHT/$RELPATH"
+        done
+        ;;
+    diff_err)
+        LEFT=$2
+        RIGHT=$3
+        for FILE in "$LEFT"/compile/*/*.err; do
+            RELPATH="${FILE##"$LEFT/"}"
+            echo "=======<$RELPATH>======="
+            diff -u "$LEFT/$RELPATH" "$RIGHT/$RELPATH"
+        done
+        ;;
+    *)
+        echo "invalid command ($CMD)"
+        ;;
+esac