diff --git a/src/relf/relf.c b/src/relf/relf.c
index 81d5386..b682613 100644
--- a/src/relf/relf.c
+++ b/src/relf/relf.c
@@ -73,6 +73,8 @@ relf_value_t relf_open(relf_t* relf, const char* path)
         TRACE("mmap failed errno %d %s\n", errno, strerror(errno));
         return RELF_ERROR(RELF_MMAP_FAILED);
     }
+
+    // now we need to parse segments and section headers
     
     return RELF_ERROR(RELF_OK);
 }
diff --git a/src/relf/relf.h b/src/relf/relf.h
index f232eed..2111cd4 100644
--- a/src/relf/relf.h
+++ b/src/relf/relf.h
@@ -15,7 +15,10 @@ typedef enum {
 typedef union {
     relf_error_t error;
 
-    uintptr_t value;
+    // yeah, we're going to always use 64bit value so
+    // we won't get any undefined behavior regardless
+    // host and target architectures
+    uint64_t value;
 } relf_value_t;
 
 // supply relf_value_t type here
@@ -27,6 +30,38 @@ typedef enum {
     RELF_32BIT
 } relf_type_t;
 
+// we're using our own structures so parsing
+// logic wouldn't be cluttered with 32 and 64 bit branching
+
+// prefix convention
+// f_   - file positioning aka file offsets
+// v_   - virtual memory in runtime
+
+// ELF program segment
+typedef struct {
+    uint32_t type;
+    uint32_t flags;
+
+    // file offset and size
+    uint64_t f_offset;
+    uint64_t f_size;
+
+    // address and size in virtual memory in runtime
+    uint64_t v_addr;
+    uint64_t v_size;
+} relf_segment_t;
+
+// ELF section
+typedef struct {
+    uint32_t type;
+    uint32_t flags;
+
+    const char* name;
+
+    uint64_t f_offset;
+    uint64_t f_size;
+} relf_section_t;
+
 // relf instance
 typedef struct {
     void* image;