diff --git a/include/perk/perk.h b/include/perk/perk.h
index bb2a05b..5951fa6 100644
--- a/include/perk/perk.h
+++ b/include/perk/perk.h
@@ -28,10 +28,6 @@ extern "C" {
 #define PERK_BAD_OPT_VAL		0x03
 #define PERK_IO_ERROR			0xA0
 #define PERK_MAP_ERROR			0xA1
-#define PERK_BAD_DOS_HEADER		0xA2
-#define PERK_BAD_COFF_HEADER		0xA3
-#define PERK_BAD_IMAGE_TYPE		0xA4
-#define PERK_MALFORMED_IMAGE		0xA5
 
 /* driver flags */
 #define PERK_DRIVER_VERBOSITY_NONE	0x0000
@@ -52,6 +48,21 @@ extern "C" {
 #define PERK_ERROR_CHILD		0x0004
 #define PERK_ERROR_CUSTOM		0x0008
 
+enum pe_custom_error {
+	PERK_ERR_FLOW_ERROR,
+	PERK_ERR_FLEE_ERROR,
+	PERK_ERR_NULL_CONTEXT,
+	PERK_ERR_NULL_IMAGE,
+	PERK_ERR_INVALID_CONTEXT,
+	PERK_ERR_INVALID_IMAGE,
+	PERK_ERR_IMAGE_SIZE_ZERO,
+	PERK_ERR_IMAGE_MALFORMED,
+	PERK_ERR_BAD_DOS_HEADER,
+	PERK_ERR_BAD_COFF_HEADER,
+	PERK_ERR_BAD_IMAGE_TYPE,
+	PERK_ERR_CAP,
+};
+
 struct pe_source_version {
 	int		major;
 	int		minor;
diff --git a/src/logic/pe_get_image_meta.c b/src/logic/pe_get_image_meta.c
index 8d90353..6302f70 100644
--- a/src/logic/pe_get_image_meta.c
+++ b/src/logic/pe_get_image_meta.c
@@ -105,7 +105,7 @@ int pe_get_image_meta(
 
 	if ((i >= 0) && (i != s))
 		return pe_free_image_meta_impl(m,
-			PERK_CUSTOM_ERROR(dctx,PERK_MALFORMED_IMAGE));
+			PERK_CUSTOM_ERROR(dctx,PERK_ERR_IMAGE_MALFORMED));
 
 	if (s >= 0) {
 		m->hedata = &m->sectbl[s];
@@ -128,7 +128,7 @@ int pe_get_image_meta(
 
 	if ((i >= 0) && (i != s))
 		return pe_free_image_meta_impl(m,
-			PERK_CUSTOM_ERROR(dctx,PERK_MALFORMED_IMAGE));
+			PERK_CUSTOM_ERROR(dctx,PERK_ERR_IMAGE_MALFORMED));
 
 	if (s >= 0) {
 		m->hidata = &m->sectbl[s];
diff --git a/src/reader/pe_read_coff_header.c b/src/reader/pe_read_coff_header.c
index 619c1cc..5ee62e3 100644
--- a/src/reader/pe_read_coff_header.c
+++ b/src/reader/pe_read_coff_header.c
@@ -15,7 +15,7 @@ int pe_read_coff_header(const struct pe_coff_file_hdr * p, struct pe_meta_coff_f
 	uint16_t * pzero = (uint16_t *)&p->signature[2];
 
 	if ((p->signature[0] != 'P') || (p->signature[1] != 'E') || *pzero)
-		return PERK_BAD_COFF_HEADER;
+		return PERK_ERR_BAD_COFF_HEADER;
 
 	if (PERK_LITTLE_ENDIAN) {
 
diff --git a/src/reader/pe_read_dos_header.c b/src/reader/pe_read_dos_header.c
index 0fd0367..7aa9ba5 100644
--- a/src/reader/pe_read_dos_header.c
+++ b/src/reader/pe_read_dos_header.c
@@ -13,7 +13,7 @@
 int pe_read_dos_header(const struct pe_image_dos_hdr * p, struct pe_meta_image_dos_hdr * m)
 {
 	if ((p->dos_magic[0] != 'M') || (p->dos_magic[1] != 'Z'))
-		return PERK_BAD_DOS_HEADER;
+		return PERK_ERR_BAD_DOS_HEADER;
 
 	if (PERK_LITTLE_ENDIAN) {
 
diff --git a/src/reader/pe_read_import_header.c b/src/reader/pe_read_import_header.c
index 645a375..d2b3acd 100644
--- a/src/reader/pe_read_import_header.c
+++ b/src/reader/pe_read_import_header.c
@@ -47,6 +47,6 @@ int pe_read_import_lookup_item(
 			return 0;
 
 		default:
-			return PERK_BAD_IMAGE_TYPE;
+			return PERK_ERR_BAD_IMAGE_TYPE;
 	}
 }
diff --git a/src/reader/pe_read_optional_header.c b/src/reader/pe_read_optional_header.c
index 24aa95b..25c1b34 100644
--- a/src/reader/pe_read_optional_header.c
+++ b/src/reader/pe_read_optional_header.c
@@ -25,7 +25,7 @@ static int pe_read_optional_header_little_endian(const union pe_opt_hdr * p, str
 			memcpy(&m->ldr,&p->opt_hdr_32.loader_flags,sizeof(struct pe_meta_opt_hdr_ldr));
 
 			if (m->ldr.rva_and_sizes > 0x10)
-				return PERK_BAD_IMAGE_TYPE;
+				return PERK_ERR_BAD_IMAGE_TYPE;
 			else
 				memcpy(&m->dirs,&p->opt_hdr_32.export_tbl,sizeof(struct pe_meta_opt_hdr_dirs));
 
@@ -38,14 +38,14 @@ static int pe_read_optional_header_little_endian(const union pe_opt_hdr * p, str
 			memcpy(&m->ldr,&p->opt_hdr_64.loader_flags,sizeof(struct pe_meta_opt_hdr_ldr));
 
 			if (m->ldr.rva_and_sizes > 0x10)
-				return PERK_BAD_IMAGE_TYPE;
+				return PERK_ERR_BAD_IMAGE_TYPE;
 			else
 				memcpy(&m->dirs,&p->opt_hdr_64.export_tbl,sizeof(struct pe_meta_opt_hdr_dirs));
 
 			break;
 
 		default:
-			return PERK_BAD_IMAGE_TYPE;
+			return PERK_ERR_BAD_IMAGE_TYPE;
 	}
 
 	return 0;
@@ -80,7 +80,7 @@ static int pe_read_optional_header_big_endian(const union pe_opt_hdr * p, struct
 			break;
 
 		default:
-			return PERK_BAD_IMAGE_TYPE;
+			return PERK_ERR_BAD_IMAGE_TYPE;
 	}
 
 	/* std */