diff --git a/book.c b/book.c
index e5f1314..0e520d2 100644
--- a/book.c
+++ b/book.c
@@ -128,10 +128,10 @@ static void subbook_undupe(Book_Subbook* subbook) {
         Book_Entry* entry = subbook->entries + i;
         Page* page = pages + entry->text.page;
 
-        bool found = false;
+        int found = 0;
         for (int j = 0; j < page->offset_count; ++j) {
             if (entry->text.offset == page->offsets[j]){
-                found = true;
+                found = 1;
                 break;
             }
         }
@@ -325,7 +325,7 @@ void book_free(Book* book) {
     memset(book, 0, sizeof(Book));
 }
 
-bool book_export(FILE* fp, const Book* book, int flags) {
+int book_export(FILE* fp, const Book* book, int flags) {
     json_t* book_json = json_object();
     book_encode(book_json, book, flags);
 
@@ -340,11 +340,11 @@ bool book_export(FILE* fp, const Book* book, int flags) {
 }
 
 
-bool book_import(Book* book, const Font_Context* context, const char path[], int flags) {
+int book_import(Book* book, const Font_Context* context, const char path[], int flags) {
     EB_Error_Code error;
     if ((error = eb_initialize_library()) != EB_SUCCESS) {
         fprintf(stderr, "Failed to initialize library: %s\n", eb_error_message(error));
-        return false;
+        return 0;
     }
 
     EB_Book eb_book;
@@ -359,7 +359,7 @@ bool book_import(Book* book, const Font_Context* context, const char path[], int
         eb_finalize_book(&eb_book);
         eb_finalize_hookset(&eb_hookset);
         eb_finalize_library();
-        return false;
+        return 0;
     }
 
     EB_Character_Code char_code;
@@ -425,5 +425,5 @@ bool book_import(Book* book, const Font_Context* context, const char path[], int
     eb_finalize_library();
 
     book_undupe(book);
-    return true;
+    return 1;
 }
diff --git a/book.h b/book.h
index fee7fb2..30e6f38 100644
--- a/book.h
+++ b/book.h
@@ -20,7 +20,6 @@
 #define BOOK_H
 
 #include <stdio.h>
-#include <stdbool.h>
 
 #include "font.h"
 
@@ -60,7 +59,7 @@ typedef struct {
 
 void book_init(Book* book);
 void book_free(Book* book);
-bool book_import(Book* book, const Font_Context* context, const char path[], int flags);
-bool book_export(FILE* fp, const Book* book, int flags);
+int book_import(Book* book, const Font_Context* context, const char path[], int flags);
+int book_export(FILE* fp, const Book* book, int flags);
 
 #endif /* BOOK_H */
diff --git a/font.c b/font.c
index 17aea2d..1d2bcd9 100644
--- a/font.c
+++ b/font.c
@@ -16,9 +16,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <string.h>
-#include <stdlib.h>
 #include <assert.h>
+#include <string.h>
 
 #include "jansson/include/jansson.h"
 
@@ -50,7 +49,7 @@ static char nibble_to_ascii(int n) {
     return n <= 0x0f ? hex[n] : 0;
 }
 
-static bool is_ascii_nibble(char c) {
+static int is_ascii_nibble(char c) {
     return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f');
 }
 
@@ -202,11 +201,11 @@ void font_stub_encode(char output[], int size, int code, const Font_Table* table
 void font_stub_decode(char output[], int size, const char input[]) {
     const char* ptr_in = input;
     char* ptr_out = output;
-    bool decode = false;
+    int decode = 0;
 
     while (*ptr_in != 0 && ptr_out - output < size - 1) {
         if (strncmp(ptr_in, "{#", 2) == 0) {
-            decode = true;
+            decode = 1;
             ptr_in += 2;
         }
 
@@ -222,7 +221,7 @@ void font_stub_decode(char output[], int size, const char input[]) {
             }
 
             if (high_ascii == '}') {
-                decode = false;
+                decode = 0;
                 --ptr_in;
             }
             else {
@@ -239,23 +238,23 @@ void font_stub_decode(char output[], int size, const char input[]) {
     *ptr_out = 0;
 }
 
-bool font_context_init(Font_Context* context, const char path[]) {
+int font_context_init(Font_Context* context, const char path[]) {
     context->table_count = 0;
     context->tables = NULL;
 
     if (path == NULL) {
-        return true;
+        return 1;
     }
 
     json_t* table_array_json = json_load_file(path, 0, NULL);
     if (table_array_json == NULL) {
         fprintf(stderr, "Failed to load font file %s\n", path);
-        return false;
+        return 0;
     }
 
     parse_table_array(context, table_array_json);
     json_decref(table_array_json);
-    return true;
+    return 1;
 }
 
 void font_context_destroy(Font_Context* context) {
diff --git a/font.h b/font.h
index af3f5af..47a0905 100644
--- a/font.h
+++ b/font.h
@@ -19,8 +19,6 @@
 #ifndef FONT_H
 #define FONT_H
 
-#include <stdbool.h>
-
 /*
  * Constants
  */
@@ -59,7 +57,7 @@ typedef enum {
  * Functions
  */
 
-bool font_context_init(Font_Context* context, const char path[]);
+int font_context_init(Font_Context* context, const char path[]);
 void font_context_destroy(Font_Context* context);
 
 const Font_Table* font_table_select(const Font_Context* context, const char name[]);
diff --git a/main.c b/main.c
index f5b66f9..a99b192 100644
--- a/main.c
+++ b/main.c
@@ -16,7 +16,6 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <stdbool.h>
 #include <stdlib.h>
 #include <getopt.h>
 
@@ -80,7 +79,7 @@ int main(int argc, char *argv[]) {
     Book book;
     book_init(&book);
 
-    const bool success =
+    const int success =
         book_import(&book, &context, dict_path, flags) &&
         book_export(stdout, &book, flags);