diff --git a/src/arguments.c b/src/arguments.c
index b6c9171..24c81ec 100644
--- a/src/arguments.c
+++ b/src/arguments.c
@@ -34,7 +34,7 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
             }
         } else {
             // flag
-            if (strncmp(s, "-t", 3) == 0) {
+            if (strcmp(s, "-t") == 0) {
                 if (argc <= 1) {
                     fprintf(stderr, "Missing test argument to '-t'\n");
                     result = TDO_ERROR_ARG_PARSE;
@@ -43,9 +43,24 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
                     args->single_test = argv[0];
                 }
             } else if (strncmp(s, "-j", 2) == 0) {
+                char const *job_str = NULL;
+                if (strcmp(s, "-j") == 0) {
+                    if (argc <= 1) {
+                        fprintf(stderr, "Missing job argument to '-j'\n");
+                        result = TDO_ERROR_ARG_PARSE;
+                        argc -= 1; argv += 1;
+                        continue;
+                    } else {
+                        argc -= 1; argv += 1;
+                        job_str = argv[0];
+                    }
+                } else {
+                    job_str = s + 2;
+                }
+
                 errno = 0;
                 char *err;
-                unsigned long threads = strtoul(s + 2, &err, 10);
+                unsigned long threads = strtoul(job_str, &err, 10);
                 if (errno) {
                     perror("Could not parse amount of processes");
                     result = TDO_ERROR_ARG_PARSE;
@@ -61,7 +76,7 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
                 } else {
                     args->processes = (size_t) threads;
                 }
-            } else if (strncmp(s, "-o", 3) == 0) {
+            } else if (strcmp(s, "-o") == 0) {
                 if (argc <= 1) {
                     fprintf(stderr, "Missing output file argument to '-o'\n");
                     result = TDO_ERROR_ARG_PARSE;
@@ -69,9 +84,9 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
                     argc -= 1; argv += 1;
                     args->output = argv[0];
                 }
-            } else if (strncmp(s, "-f", 3) == 0) {
+            } else if (strcmp(s, "-f") == 0) {
                 args->overwrite = true;
-            } else if (strncmp(s, "--internal-status", 18) == 0) {
+            } else if (strcmp(s, "--internal-status") == 0) {
                 if (argc <= 1) {
                     fprintf(stderr, "Missing status file\n");
                     result = TDO_ERROR_ARG_PARSE;
@@ -79,9 +94,9 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
                     argc -= 1; argv += 1;
                     args->internal_status = argv[0];
                 }
-            } else if (strncmp(s, "--timeout", 10) == 0) {
+            } else if (strcmp(s, "--timeout") == 0) {
                 if (argc <= 1) {
-                    fprintf(stderr, "Missing timeout argument\n");
+                    fprintf(stderr, "Missing timeout argument to '--timeout'\n");
                     result = TDO_ERROR_ARG_PARSE;
                 } else {
                     argc -= 1; argv += 1;
@@ -91,13 +106,13 @@ enum TdoError tdo_arguments_parse(struct TdoArguments *args, int argc, char **ar
                     char *err;
                     float timeout = strtof(timeout_str, &err);
                     if (errno) {
-                        perror("Could not parse amount of processes");
+                        perror("Could not parse timeout");
                         result = TDO_ERROR_ARG_PARSE;
                     } else if (*err != '\0') {
-                        fprintf(stderr, "Could not parse amount of threads: '%s'\n", timeout_str);
+                        fprintf(stderr, "Could not parse timeout: '%s'\n", timeout_str);
                         result = TDO_ERROR_ARG_PARSE;
                     } else if (timeout <= 0) {
-                        fprintf(stderr, "Amount of processes must be strictly positive, got %f\n", timeout);
+                        fprintf(stderr, "Timeout must be strictly positive, got %f\n", timeout);
                         result = TDO_ERROR_ARG_PARSE;
                     } else {
                         args->time_limit = timeout;
diff --git a/src/main.c b/src/main.c
index 1f25ae0..d7ee594 100644
--- a/src/main.c
+++ b/src/main.c
@@ -18,10 +18,52 @@
 
 #include <errno.h>
 #include <stdio.h>
+#include <string.h>
+
+static const char *tdo_help_text =
+    "Usage: tdo [OPTIONS] [TEST_FILE]\n"
+    "       tdo [OPTIONS] -t \"TEST_DEFINITION\"\n"
+    "       cat tests.txt | tdo [OPTIONS]\n"
+    "\n"
+    "A C99 test runner that executes tests defined by shared library symbols.\n"
+    "Every test is executed in a separate process which ensures that they do not\n"
+    "interact.\n"
+    "\n"
+    "Arguments:\n"
+    "  TEST_FILE             Path to a file containing test definitions. If omitted \n"
+    "                        and no -t flag is provided, definitions are read \n"
+    "                        from standard input (stdin).\n"
+    "\n"
+    "Options:\n"
+    "  -t \"TEST_DEFINITION\"  Run a single test definition string directly.\n"
+    "  -j [N]                Run tests in parallel using N processes (default: 1).\n"
+    "  -o FILE               Write results to the specified FILE.\n"
+    "  -f                    Force overwrite the output file if it already exists.\n"
+    "  --timeout SECONDS     Set a maximum execution time per test (default: 5.0).\n"
+    "  -h, --help            Display this help message and exit.\n"
+    "\n"
+    "Test Definition Format:\n"
+    "  Definitions follow a \"test-first\" structure:\n"
+    "    test::PATH::SYMBOL [before::PATH::SYMBOL] [after::PATH::SYMBOL] ...\n"
+    "\n"
+    "  - PATH:   The path to the shared library (e.g., .so, .dll, or .dylib).\n"
+    "  - SYMBOL: The name of the exported function to execute.\n"
+    "\n"
+    "  Definitions can include any number of 'before' and 'after' hooks.\n"
+    "  Example:\n"
+    "    test::./lib.so::test_math before::./lib.so::setup after::./lib.so::clean\n"
+;
 
 int main(int argc, char **argv) {
     enum TdoError result = TDO_ERROR_UNKNOWN;
 
+    for (int i = 0; i < argc; i++) {
+        if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0) {
+            fprintf(stderr, "%s", tdo_help_text);
+            return TDO_ERROR_OK;
+        }
+    }
+
     struct TdoArguments args;
     result = tdo_arguments_parse(&args, argc, argv);
     if (result != TDO_ERROR_OK) goto error_parse_args;