diff --git a/run-tests.sh b/run-tests.sh
new file mode 100755
index 0000000..d677621
--- /dev/null
+++ b/run-tests.sh
@@ -0,0 +1,136 @@
+#!/bin/sh
+
+help() {
+    echo "How to use test suite:"
+    echo "\tCreate a file with the format test_[a-z]+.hy in the tests directory"
+    echo "\tMake the first line a comment with the expected exit code: E.g. // exit 1"
+    echo "\tIf there's any stdout you want to test, create a file with the same name but with .txt instead of .hy"
+    echo "\tThe script will then do a diff compare to make sure it's the same"
+    echo "\tNo need to provide the .txt file if there's no output to test"
+    echo
+}
+
+
+## Variables 
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+RESET='\033[0m'
+PASS=0
+FAIL=0
+TOTAL=0
+
+# Helpful details for shell script
+if [ "$#" -ne "0" ]
+then
+    if [ "$1" = "--help" ] || [ "$1" = "-h" ]
+    then 
+        help
+    fi
+fi
+
+
+for file in tests/*
+do
+    file=$(basename $file)
+
+    # Ignoring any other random files that aren't .txt or .hy
+    if ! (echo $file | grep -Eq "test_[a-z]+\.(hy|txt)$")
+    then
+        echo "Skipping over ${YELLOW}${file}${RESET}: invalid filename"
+        continue
+    fi
+
+    # If it's not a .hy file, ignore
+    if ! echo $file | grep -Eq "\.hy$"
+    then 
+        continue
+    fi
+
+
+    EXIT_CODE=$(head -n1 tests/"$file" | grep -Eo "[0-9]+$")
+    if  [ "$EXIT_CODE" = "" ]
+    then 
+        echo "Skipping over ${YELLOW}${file}${RESET}: please provide exit code in first line"
+        continue
+    fi
+
+    # Attempt to build the executable
+    ./build/hydro tests/"$file" >> /dev/null >&2
+
+    # Build failed
+    if [ "$?" -ne "0" ]
+    then
+        echo "${RED}Build error${RESET} for ${YELLOW}${file}${RESET}, counting as fail"
+        FAIL=$((FAIL + 1))
+        TOTAL=$((TOTAL + 1)) 
+        continue
+    fi 
+
+    # Now execute commands and compare to the test_one.txt file
+    rootName=$(echo "$file" | grep -Eo "^test_[a-z]+")
+    if [ -f "tests/${rootName}.txt" ]
+    then 
+        # Also need to compare stdout
+        ./out > "tests/current_output"
+        if [ "$EXIT_CODE" -ne "$?" ]
+        then 
+            echo "${RED}Fail${RESET} for ${YELLOW}${file}${RESET}, differing exit codes"
+            FAIL=$((FAIL + 1))
+        else
+
+            if diff "tests/current_output" "tests/${rootName}.txt" > /dev/null
+            then
+                # They are identical
+                echo "${GREEN}Pass${RESET} for ${YELLOW}${file}${RESET}, same exit code and stdout"
+                PASS=$((PASS + 1))
+            else
+                # They aren't identical
+                echo "${RED}Fail${RESET} for ${YELLOW}${file}${RESET}, differing stdout, same exit code"
+                FAIL=$((FAIL + 1))
+            fi 
+            TOTAL=$((TOTAL + 1)) 
+        fi
+
+    else
+        # Don't bother comparing stdout
+        ./out 
+        if [ "$EXIT_CODE" -eq "$?" ]
+        then
+            echo "${GREEN}Pass${RESET} for ${YELLOW}${file}${RESET}, same exit code"
+            PASS=$((PASS + 1))
+        else 
+            echo "${RED}Fail${RESET} for ${YELLOW}${file}${RESET}, differing exit codes"
+            FAIL=$((FAIL + 1))
+        fi 
+        TOTAL=$((TOTAL + 1)) 
+    fi
+
+done
+
+if [ -f "tests/current_output" ]
+then 
+    rm tests/current_output
+fi
+
+if [ -f "out" ]
+then 
+    rm out
+fi
+
+if [ -f "out.asm" ]
+then 
+    rm "out.asm"
+fi
+
+if [ -f "out.o" ]
+then 
+    rm "out.o"
+fi
+
+echo
+echo "Test suite completed: "
+echo "\t${GREEN}${PASS} passed${RESET}"
+echo "\t${RED}${FAIL} failed${RESET}"
+echo "\t${TOTAL} total"
+
diff --git a/tests/test_one.hy b/tests/test_one.hy
new file mode 100644
index 0000000..f32bd05
--- /dev/null
+++ b/tests/test_one.hy
@@ -0,0 +1,17 @@
+// expected exit: 5
+let y = (10 - 2 * 3); 
+let x = 7; // first
+// first
+if (0) {
+    x = 1;
+} elif (0) {
+    x = 2;
+} else {
+    x = 5;
+}
+
+exit(x);
+
+/*
+exit(4);
+*/
diff --git a/tests/test_three.hy b/tests/test_three.hy
new file mode 100644
index 0000000..4883989
--- /dev/null
+++ b/tests/test_three.hy
@@ -0,0 +1,13 @@
+// 0
+
+let y = 5;
+let x = 0;
+
+if (x) {
+    x = x + 1;
+} else {
+    y = 0;
+}
+
+
+exit(y);
\ No newline at end of file
diff --git a/tests/test_two.hy b/tests/test_two.hy
new file mode 100644
index 0000000..5523576
--- /dev/null
+++ b/tests/test_two.hy
@@ -0,0 +1,2 @@
+// 1
+exit(1);
\ No newline at end of file