diff --git a/src/args.c b/src/args.c
new file mode 100644
index 0000000..bdf8ea7
--- /dev/null
+++ b/src/args.c
@@ -0,0 +1,72 @@
+#include "args.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+void kwil_parse_args(struct kwil_args_t* self, int argc, char** argv) {
+    self->argc = argc;
+    self->argv = argv;
+    self->parsed = 0;
+
+    // allocate filename array with capacity of 1
+    self->filenames = malloc(sizeof(char**));
+    self->filenames_cap = 1;
+    self->filenames_len = 0;
+
+    for(self->parsed = 0; self->parsed < argc; ++self->parsed) {
+        kwil_args_parse_arg(self, self->parsed);
+    }
+}
+
+void kwil_free_args(struct kwil_args_t* self) {
+    for(int i = 0; i < self->filenames_len; ++i) {
+        free(self->filenames[i]);
+    }
+
+    free(self->filenames);
+    self->filenames_cap = 0;
+    self->filenames_len = 0;
+}
+
+int kwil_args_add_filename(struct kwil_args_t* self, const char* filename) {
+    // resize the array if needed
+    if(self->filenames_len >= self->filenames_cap) {
+        size_t new_cap = self->filenames_cap * 2;
+        char** new_array = realloc(self->filenames, new_cap * sizeof(char**));
+        if(new_array == NULL) {
+            return 1;
+        }
+        self->filenames_cap = new_cap;
+        self->filenames = new_array;
+    }
+
+    // allocate enough memory for the string and null terminator
+    size_t len = strlen(filename);
+    self->filenames[self->filenames_len] = malloc(len + 1);
+    // copy string (includes null terminator)
+    strcpy(self->filenames[self->filenames_len], filename);
+
+    ++self->filenames_len;
+
+    return 0;
+}
+
+void kwil_args_parse_arg(struct kwil_args_t* self, int at) {
+    if(at == 0) {
+        // is program argument, ignore
+    } else if(self->argv[at][0] == '-') {
+        // is a flag, parse flag
+        // no flags to parse
+    } else {
+        // asume a filename
+        kwil_args_parse_filename(self, at);
+    }
+}
+
+void kwil_args_parse_filename(struct kwil_args_t* self, int filename) {
+    const char* filename_str = self->argv[filename];
+    int len = strlen(filename_str);
+    if(strcmp(filename_str + len - 7, ".kwil.h") != 0) {
+        kwil_args_add_filename(self, filename_str);
+    }
+}
diff --git a/src/args.h b/src/args.h
new file mode 100644
index 0000000..9c043b6
--- /dev/null
+++ b/src/args.h
@@ -0,0 +1,30 @@
+#ifndef _ARGS_H
+#define _ARGS_H
+
+#include <stddef.h>
+
+struct kwil_args_t {
+    int argc; // copy of the argv length passed to main
+    char** argv; // pointer to the argv array passed to main
+    int parsed; // the number of arguments parsed so far
+
+    char** filenames;           // filenames to process
+    size_t filenames_len;       // number of filenames to process
+    size_t filenames_cap;       // allocated capacity of filenames array
+};
+
+// Instantiate a kwil_args_t and parse the arguments array for flags and files
+extern void kwil_parse_args(struct kwil_args_t* self, int argc, char** argv);
+// Free an arguments object's owned memory.
+// Does not free the self*.
+extern void kwil_free_args(struct kwil_args_t* self);
+
+// Add a filename to the filename array and increase capacity if needed.
+extern int kwil_args_add_filename(struct kwil_args_t* self, const char* filename);
+
+// Parse an argument
+extern void kwil_args_parse_arg(struct kwil_args_t* self, int at);
+// Parse a filename argument
+extern void kwil_args_parse_filename(struct kwil_args_t* self, int at);
+
+#endif // !_ARGS_H