diff --git a/kernel/src/MemoryManager.cpp b/kernel/src/MemoryManager.cpp
index f1ae9961..63153a92 100644
--- a/kernel/src/MemoryManager.cpp
+++ b/kernel/src/MemoryManager.cpp
@@ -157,7 +157,7 @@ namespace MemoryManager
         return {};
     }
 
-    Result<void> remap(u64 address, size_t count, int flags)
+    Result<void> remap(u64 address, usize count, int flags)
     {
         check(is_aligned(address, MMU::page_size()));
 
@@ -170,7 +170,7 @@ namespace MemoryManager
         return {};
     }
 
-    Result<void> remap_unaligned(u64 address, size_t count, int flags)
+    Result<void> remap_unaligned(u64 address, usize count, int flags)
     {
         if (!is_aligned(address, MMU::page_size())) count++;
         address = align_down(address, MMU::page_size());
diff --git a/kernel/src/MemoryManager.h b/kernel/src/MemoryManager.h
index ab516b5b..d1ca0f5f 100644
--- a/kernel/src/MemoryManager.h
+++ b/kernel/src/MemoryManager.h
@@ -14,8 +14,8 @@ namespace MemoryManager
     void lock_page(u64 page);
     void lock_pages(u64 pages, u64 count);
 
-    Result<void> remap(u64 address, size_t count, int flags);
-    Result<void> remap_unaligned(u64 address, size_t count, int flags);
+    Result<void> remap(u64 address, usize count, int flags);
+    Result<void> remap_unaligned(u64 address, usize count, int flags);
 
     u64 free();
     u64 used();
diff --git a/kernel/src/arch/MMU.h b/kernel/src/arch/MMU.h
index 624427f6..b0ccc8b3 100644
--- a/kernel/src/arch/MMU.h
+++ b/kernel/src/arch/MMU.h
@@ -29,5 +29,5 @@ namespace MMU
     Result<PageDirectory*> create_page_directory_for_userspace();
     void setup_initial_page_directory();
 
-    size_t page_size();
+    usize page_size();
 }
\ No newline at end of file
diff --git a/kernel/src/arch/Serial.cpp b/kernel/src/arch/Serial.cpp
index 958557f6..ddf3a879 100644
--- a/kernel/src/arch/Serial.cpp
+++ b/kernel/src/arch/Serial.cpp
@@ -2,7 +2,7 @@
 
 namespace Serial
 {
-    void write(const char* str, size_t size)
+    void write(const char* str, usize size)
     {
         while (size--) putchar(*str++);
     }
diff --git a/kernel/src/arch/Serial.h b/kernel/src/arch/Serial.h
index 031aaac0..8d7b18aa 100644
--- a/kernel/src/arch/Serial.h
+++ b/kernel/src/arch/Serial.h
@@ -4,7 +4,7 @@
 namespace Serial
 {
     void putchar(u8 c);
-    void write(const char* str, size_t size);
+    void write(const char* str, usize size);
     void print(const char* str);
     void println(const char* str);
 }
\ No newline at end of file
diff --git a/kernel/src/arch/x86_64/MMU.cpp b/kernel/src/arch/x86_64/MMU.cpp
index e259eb47..fda4c36c 100644
--- a/kernel/src/arch/x86_64/MMU.cpp
+++ b/kernel/src/arch/x86_64/MMU.cpp
@@ -52,7 +52,7 @@ static_assert(sizeof(PageDirectory) == PAGE_SIZE);
 
 namespace MMU
 {
-    size_t page_size()
+    usize page_size()
     {
         return PAGE_SIZE;
     }
diff --git a/luna/Types.h b/luna/Types.h
index c45e4448..ad06edfe 100644
--- a/luna/Types.h
+++ b/luna/Types.h
@@ -8,4 +8,6 @@ typedef uint64_t u64;
 typedef int8_t i8;
 typedef int16_t i16;
 typedef int32_t i32;
-typedef int64_t i64;
\ No newline at end of file
+typedef int64_t i64;
+typedef size_t usize;
+typedef long isize;
\ No newline at end of file