diff --git a/Makefile b/Makefile
index f2d0f83..c37e5c6 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 CC = gcc
 CPPFLAGS = -Isrc/ -D_POSIX_C_SOURCE=200809L -D_USE_CLIMBING=$(USE_CLIMBING)
 CFLAGS = -Wall -Wextra -pedantic -Werror -std=c99
-VPATH = src/
+VPATH = src/ tests/
 USE_CLIMBING = 1
 
 SRC = \
@@ -19,6 +19,20 @@ all: $(BIN)
 # Write this one rule instead of using the implicit rules to buid at the root
 $(BIN): $(OBJ) src/evalexpr.o
 
+check: testsuite
+	./testsuite --verbose
+
+TEST_SRC = \
+    tests/climbing.c \
+    tests/recursive.c \
+    tests/testsuite.c \
+
+TEST_OBJ = $(TEST_SRC:.c=.o)
+
+testsuite: LDFLAGS+=-lcriterion -fsanitize=address
+testsuite: CFLAGS+=-fsanitize=address
+testsuite: $(OBJ) $(TEST_OBJ)
+
 .PHONY: clean
 clean:
 	$(RM) $(OBJ) # remove object files
diff --git a/tests/climbing.c b/tests/climbing.c
new file mode 100644
index 0000000..b80bd93
--- /dev/null
+++ b/tests/climbing.c
@@ -0,0 +1,181 @@
+#include <criterion/criterion.h>
+
+#include "ast/ast.h"
+#include "eval/eval.h"
+#include "parse/parse.h"
+
+static void do_success(const char *input, int expected)
+{
+    struct ast_node *ast = climbing_parse(input);
+
+    cr_assert_not_null(ast);
+    cr_expect_eq(eval_ast(ast), expected);
+
+    destroy_ast(ast);
+}
+
+static void do_failure(const char *input)
+{
+    struct ast_node *ast = climbing_parse(input);
+
+    cr_expect_null(ast);
+
+    destroy_ast(ast); // Do not leak if it exists
+}
+
+TestSuite(climbing);
+
+Test(climbing, empty)
+{
+    do_failure("");
+}
+
+Test(climbing, trailing_operator)
+{
+    do_failure("1 +");
+}
+
+Test(climbing, trailing_expression)
+{
+    do_failure("1 1");
+}
+
+Test(climbing, double_operator)
+{
+    do_failure("1 * * 1");
+}
+
+Test(climbing, one)
+{
+    do_success("1", 1);
+}
+
+Test(climbing, the_answer)
+{
+    do_success("42", 42);
+}
+
+Test(climbing, int_max)
+{
+    do_success("2147483647", 2147483647);
+}
+
+Test(climbing, whitespace)
+{
+    do_success("   1   ", 1);
+}
+
+Test(climbing, more_whitespace)
+{
+    do_success("   1   + 2     ", 3);
+}
+
+Test(climbing, one_plus_one)
+{
+    do_success("1+1", 2);
+}
+
+Test(climbing, one_minus_one)
+{
+    do_success("1-1", 0);
+}
+
+Test(climbing, additions)
+{
+    do_success("1+1+1+1+1", 5);
+}
+
+Test(climbing, substractions)
+{
+    do_success("1-1-1-1-1", -3);
+}
+
+Test(climbing, multiplication)
+{
+    do_success("2 * 3", 6);
+}
+
+Test(climbing, multiplications)
+{
+    do_success("1 * 2 * 3 * 4", 24);
+}
+
+Test(climbing, division)
+{
+    do_success("12 / 3", 4);
+}
+
+Test(climbing, divisions)
+{
+    do_success("24 / 4 / 3 / 2", 1);
+}
+
+Test(climbing, simple_priority)
+{
+    do_success("1 + 2 * 3", 7);
+}
+
+Test(climbing, more_priority)
+{
+    do_success("1 + 6 / 3 + 4 * 6 + 14 / 7", 29);
+}
+
+Test(climbing, fail_parenthesis)
+{
+    do_failure("(1 + 2))");
+}
+
+Test(climbing, simple_parenthesis)
+{
+    do_success("(1 + 2) * 3", 9);
+}
+
+Test(climbing, more_parentheses)
+{
+    do_success("(1 + 2) * (3 - 4)", -3);
+}
+
+Test(climbing, unary_minus)
+{
+    do_success("-1", -1);
+}
+
+Test(climbing, unary_plus)
+{
+    do_success("+1", 1);
+}
+
+Test(climbing, unary_torture)
+{
+    do_success("--+++--+-+-+-1", -1);
+}
+
+Test(climbing, factorial)
+{
+    do_success("3!", 6);
+}
+
+Test(climbing, fail_factorial)
+{
+    do_failure("3!!");
+}
+
+Test(climbing, power)
+{
+    do_success("4^3", 64);
+}
+
+Test(climbing, powers)
+{
+    do_success("4^3^2", 262144);
+}
+
+Test(climbing, fact_and_power)
+{
+    do_success("2^3!", 64);
+}
+
+Test(climbing, altogether)
+{
+    do_success("  -   3 ^ 2 + - 4 * 8 / 2 + + 3! -- 2 + ((-1) + 1) * 2 ", -17);
+}
diff --git a/tests/recursive.c b/tests/recursive.c
new file mode 100644
index 0000000..dcc0a9d
--- /dev/null
+++ b/tests/recursive.c
@@ -0,0 +1,181 @@
+#include <criterion/criterion.h>
+
+#include "ast/ast.h"
+#include "eval/eval.h"
+#include "parse/parse.h"
+
+static void do_success(const char *input, int expected)
+{
+    struct ast_node *ast = recursive_parse(input);
+
+    cr_assert_not_null(ast);
+    cr_expect_eq(eval_ast(ast), expected);
+
+    destroy_ast(ast);
+}
+
+static void do_failure(const char *input)
+{
+    struct ast_node *ast = recursive_parse(input);
+
+    cr_expect_null(ast);
+
+    destroy_ast(ast); // Do not leak if it exists
+}
+
+TestSuite(recursive);
+
+Test(recursive, empty)
+{
+    do_failure("");
+}
+
+Test(recursive, trailing_operator)
+{
+    do_failure("1 +");
+}
+
+Test(recursive, trailing_expression)
+{
+    do_failure("1 1");
+}
+
+Test(recursive, double_operator)
+{
+    do_failure("1 * * 1");
+}
+
+Test(recursive, one)
+{
+    do_success("1", 1);
+}
+
+Test(recursive, the_answer)
+{
+    do_success("42", 42);
+}
+
+Test(recursive, int_max)
+{
+    do_success("2147483647", 2147483647);
+}
+
+Test(recursive, whitespace)
+{
+    do_success("   1   ", 1);
+}
+
+Test(recursive, more_whitespace)
+{
+    do_success("   1   + 2     ", 3);
+}
+
+Test(recursive, one_plus_one)
+{
+    do_success("1+1", 2);
+}
+
+Test(recursive, one_minus_one)
+{
+    do_success("1-1", 0);
+}
+
+Test(recursive, additions)
+{
+    do_success("1+1+1+1+1", 5);
+}
+
+Test(recursive, substractions)
+{
+    do_success("1-1-1-1-1", -3);
+}
+
+Test(recursive, multiplication)
+{
+    do_success("2 * 3", 6);
+}
+
+Test(recursive, multiplications)
+{
+    do_success("1 * 2 * 3 * 4", 24);
+}
+
+Test(recursive, division)
+{
+    do_success("12 / 3", 4);
+}
+
+Test(recursive, divisions)
+{
+    do_success("24 / 4 / 3 / 2", 1);
+}
+
+Test(recursive, simple_priority)
+{
+    do_success("1 + 2 * 3", 7);
+}
+
+Test(recursive, more_priority)
+{
+    do_success("1 + 6 / 3 + 4 * 6 + 14 / 7", 29);
+}
+
+Test(recursive, fail_parenthesis)
+{
+    do_failure("(1 + 2))");
+}
+
+Test(recursive, simple_parenthesis)
+{
+    do_success("(1 + 2) * 3", 9);
+}
+
+Test(recursive, more_parentheses)
+{
+    do_success("(1 + 2) * (3 - 4)", -3);
+}
+
+Test(recursive, unary_minus)
+{
+    do_success("-1", -1);
+}
+
+Test(recursive, unary_plus)
+{
+    do_success("+1", 1);
+}
+
+Test(recursive, unary_torture)
+{
+    do_success("--+++--+-+-+-1", -1);
+}
+
+Test(recursive, factorial)
+{
+    do_success("3!", 6);
+}
+
+Test(recursive, fail_factorial)
+{
+    do_failure("3!!");
+}
+
+Test(recursive, power)
+{
+    do_success("4^3", 64);
+}
+
+Test(recursive, powers)
+{
+    do_success("4^3^2", 262144);
+}
+
+Test(recursive, fact_and_power)
+{
+    do_success("2^3!", 64);
+}
+
+Test(recursive, altogether)
+{
+    do_success("  -   3 ^ 2 + - 4 * 8 / 2 + + 3! -- 2 + ((-1) + 1) * 2 ", -17);
+}
diff --git a/tests/testsuite.c b/tests/testsuite.c
new file mode 100644
index 0000000..4a2e43b
--- /dev/null
+++ b/tests/testsuite.c
@@ -0,0 +1,13 @@
+#include <criterion/criterion.h>
+
+int main(int argc, char *argv[])
+{
+    struct criterion_test_set *tests = criterion_initialize();
+
+    int result = 0;
+    if (criterion_handle_args(argc, argv, true))
+        result = !criterion_run_all_tests(tests);
+
+    criterion_finalize(tests);
+    return result;
+}