diff --git a/src/compile_flags.txt b/src/compile_flags.txt
index 1169529..b77fb74 100644
--- a/src/compile_flags.txt
+++ b/src/compile_flags.txt
@@ -3,5 +3,6 @@
 -DED_STRING_IMPLEMENTATION
 -DED_GFX_IMPLEMENTATION
 -DED_BUFFER_IMPLEMENTATION
+-DED_FILE_IO_IMPLEMENTATION
 -I../vendor/
 -ObjC
diff --git a/src/file_io.h b/src/file_io.h
new file mode 100644
index 0000000..f2f0c79
--- /dev/null
+++ b/src/file_io.h
@@ -0,0 +1,138 @@
+#ifndef ED_FILE_IO_INCLUDED
+#define ED_FILE_IO_INCLUDED
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "string.h"
+
+uint64_t get_file_size(string file_path);
+bool load_file(string file_path, size_t size, void *buffer);
+
+#ifdef ED_FILE_IO_IMPLEMENTATION
+
+#if defined(__unix__)
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+unsigned long get_file_size(const char *filePath) {
+    FILE *file = fopen(filePath, "r");
+    assert(file && "get_file_size: failed to open file");
+
+    fseek(file, 0, SEEK_END);
+    long fsize = ftell(file);
+    fseek(file, 0, SEEK_SET);
+
+    fclose(file);
+
+    return fsize;
+}
+
+bool load_file(const char *filePath, unsigned long size, void *buffer) {
+    FILE *file = fopen(filePath, "r");
+    assert(file && "load_file: failed to open file");
+
+    fseek(file, 0, SEEK_END);
+    long fsize = ftell(file);
+    fseek(file, 0, SEEK_SET);
+
+    fread(buffer, fsize, 1, file);
+
+    fclose(file);
+
+    return true;
+}
+
+#elif defined(_WIN32) || defined(WIN32)
+#include <windows.h>
+#define assertm(exp, msg) assert(((void)msg, exp))
+
+VOID CALLBACK FileIOCompletionRoutine(
+        __in  DWORD dwErrorCode,
+        __in  DWORD dwNumberOfBytesTransfered,
+        __in  LPOVERLAPPED lpOverlapped )
+{
+    printf("Error code: %li", dwErrorCode);
+    printf("Number of bytes: %li", dwNumberOfBytesTransfered);
+}
+
+unsigned long get_file_size(const char *filePath) {
+    HANDLE hFile = CreateFile(filePath,
+            GENERIC_READ,
+            FILE_SHARE_READ,
+            NULL,
+            OPEN_EXISTING,
+            FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED,
+            NULL);
+
+    LARGE_INTEGER size;
+    assert(GetFileSizeEx(hFile, &size) && "get_file_size: failed to get file size");
+
+    return size.LowPart;
+}
+
+bool load_file(const char *filePath, unsigned long size, void *buffer) {
+    HANDLE hFile = CreateFile(filePath,
+            GENERIC_READ,
+            FILE_SHARE_READ,
+            NULL,
+            OPEN_EXISTING,
+            FILE_ATTRIBUTE_NORMAL,
+            NULL);
+
+    OVERLAPPED ol = {0};
+    unsigned long bytesRead = 0;
+    if (!ReadFile(hFile, buffer, size, &bytesRead, NULL)) {
+        unsigned long error = GetLastError();
+        unsigned long msg = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, buffer, size, NULL);
+
+        printf("failed to load file: %s\n", (char *)buffer);
+        assert(false && "failed to read file");
+    }
+    assert(bytesRead == size && "load_file: didn't one-shot read the whole file");
+
+    return true;
+}
+#elif defined(__APPLE__)
+#include <Foundation/Foundation.h>
+
+uint64_t get_file_size(string file_path) {
+    NSFileManager* file_manager = [NSFileManager defaultManager];
+    NSString *path = [file_manager stringWithFileSystemRepresentation:(const char *)file_path.data length:file_path.len]; 
+
+    NSError *error = NULL;
+    NSDictionary<NSFileAttributeKey, id> *attributes = [file_manager attributesOfItemAtPath:path error:&error];
+
+    if (error) {
+        NSLog(@"error getting file attributes: %@\n", error.description);
+        return 0;
+    }
+
+    NSNumber *file_size = [attributes objectForKey:NSFileSize];
+    
+    return file_size.unsignedLongLongValue;
+}
+
+bool load_file(string file_path, size_t size, void *buffer) {
+    NSFileManager* file_manager = [NSFileManager defaultManager];
+    NSString *path = [file_manager stringWithFileSystemRepresentation:(const char *)file_path.data length:file_path.len]; 
+
+    NSData *data = [file_manager contentsAtPath:path];
+    if (data == NULL) {
+        fprintf(stderr, "failed to load file: %.*s\n", (int)file_path.len, file_path.data);
+        return false;
+    }
+
+    if (data.length > size) {
+        fprintf(stderr, "buffer not large enough for file: %.*s\n", (int)file_path.len, file_path.data);
+    }
+
+    memcpy(buffer, data.bytes, data.length);
+
+    return true;
+}
+
+#endif
+
+#endif
+#endif
diff --git a/src/main.c b/src/main.c
index ed5e69a..025b68c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -12,12 +12,14 @@
 #define ED_HT_IMPLEMENTATION
 #define ED_UI_IMPLEMENTATION
 #define ED_BUFFER_IMPLEMENTATION
+#define ED_FILE_IO_IMPLEMENTATION
 #include "string.h"
 #include "ht.h"
 #include "ui.h"
 #include "ed_array.h"
 #include "gfx.h"
 #include "buffer.h"
+#include "file_io.h"
 
 // static Arena default_arena = {0};
 // static Arena temporary_arena = {0};
@@ -112,15 +114,9 @@ void ed_init(_gfx_frame_func frame_func) {
     gfx_allocate_vertex_buffer(state.gfx_cx, sizeof(GpuUniformParams));
     gfx_allocate_vertex_buffer(state.gfx_cx, state.gpu_ui_rects.capacity * sizeof(GpuUiRect));
 
-    uint8_t ttf_buffer[1<<20];
     // TODO: grab default font from the system
-    FILE *ttf_file = fopen("./bin/JetBrainsMono-Medium.ttf", "rb");
-    if (!ttf_file) {
-        fprintf(stderr, "failed to load font\n");
-        exit(1);
-    }
-    assert(fread(ttf_buffer, 1, 1<<20, ttf_file));
-    fclose(ttf_file);
+    uint8_t ttf_buffer[1<<20];
+    assert("failed to load font" && load_file(_String("./bin/JetBrainsMono-Medium.ttf"), 1<<20, ttf_buffer));
 
     stbtt_fontinfo font;
     stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer, 0));