diff --git a/test/append_test.sh b/test/append_test.sh
new file mode 100755
index 0000000..e6ceb99
--- /dev/null
+++ b/test/append_test.sh
@@ -0,0 +1,15 @@
+#! /bin/bash
+
+testAppendToEmptyList() {
+  assertEquals 4 "$(list | append 4)"
+}
+
+testAppendToOneElementList() {
+  assertEquals "1 4" "$(list 1 | append 4 | unlist)"
+}
+
+testAppendToList() {
+  assertEquals "1 2 3 4 5 4" "$(list 1 2 3 4 5 | append 4 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/drop_test.sh b/test/drop_test.sh
old mode 100644
new mode 100755
diff --git a/test/head_test.sh b/test/head_test.sh
old mode 100644
new mode 100755
diff --git a/test/lambda_test.sh b/test/lambda_test.sh
new file mode 100755
index 0000000..4e035bd
--- /dev/null
+++ b/test/lambda_test.sh
@@ -0,0 +1,30 @@
+#! /bin/bash
+
+testLambdaOneArgument() {
+  identity() {
+    lambda x . '$x'
+  }
+  assertEquals "hi there !" "$(identity <<< 'echo hi there !')"
+  assertEquals 3 $(lambda x . 'echo $(($x + 1))' <<< '2')
+  assertEquals "hi there !" "$(λ x . 'echo $x' <<< 'hi there !')"
+}
+
+testLambdaSymbolTwoArguments() {
+    assertEquals 3 $(echo -e '1\n2' | lambda x y . 'echo $(($x + $y))')
+    assertEquals 5 $(echo -e '7\n2' | λ x y . 'echo $(($x - $y))')
+}
+
+testLambdaSymbolManyArguments() {
+    assertEquals 5 $(echo -e '1\n2\n3\n4\n5' | lambda a b c d e . 'echo $(($a + $b + $c + $d - $e))')
+}
+
+testLambdaSymbolManyArguments_ifInsufficientNumberOfArgumentsInLambda() {
+    assertEquals 6 $(echo -e '1\n2\n3\n4\n5' | lambda a b c . 'echo $(($a + $b + $c))')
+}
+
+testLambdaSymbolManyArguments_ifInsufficientNumberOfInputArguments() {
+    echo -e '1\n2' | lambda a b c d e . 'echo $(($a + $b + $c + $d + $e))' 2> /dev/null \
+        && fail "There should be syntax error"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/last_test.sh b/test/last_test.sh
old mode 100644
new mode 100755
diff --git a/test/list_test.sh b/test/list_test.sh
old mode 100644
new mode 100755
diff --git a/test/prepend_test.sh b/test/prepend_test.sh
new file mode 100755
index 0000000..8e9e3a0
--- /dev/null
+++ b/test/prepend_test.sh
@@ -0,0 +1,15 @@
+#! /bin/bash
+
+testPrependToEmptyList() {
+  assertEquals 4 "$(list | prepend 4)"
+}
+
+testPrependToOneElementList() {
+  assertEquals "4 1" "$(list 1 | prepend 4 | unlist)"
+}
+
+testPrependToList() {
+  assertEquals "4 1 2 3 4 5" "$(list 1 2 3 4 5 | prepend 4 | unlist)"
+}
+
+. ./shunit2-init.sh
\ No newline at end of file
diff --git a/test/tail_test.sh b/test/tail_test.sh
old mode 100644
new mode 100755
diff --git a/test/take_test.sh b/test/take_test.sh
old mode 100644
new mode 100755
diff --git a/test/unlist_test.sh b/test/unlist_test.sh
old mode 100644
new mode 100755