diff --git a/core/c/libc/errno.odin b/core/c/libc/errno.odin
index 138d70a80..1f6df52f7 100644
--- a/core/c/libc/errno.odin
+++ b/core/c/libc/errno.odin
@@ -80,25 +80,6 @@ when ODIN_OS == .Darwin {
 	ERANGE :: 34
 }
 
-when ODIN_OS == .Haiku {
-	@(private="file")
-	@(default_calling_convention="c")
-	foreign libc {
-		@(link_name="_errnop")
-		_get_errno :: proc() -> ^int ---
-	}
-
-	_HAIKU_USE_POSITIVE_POSIX_ERRORS :: #config(HAIKU_USE_POSITIVE_POSIX_ERRORS, false)
-	_POSIX_ERROR_FACTOR              :: -1 when _HAIKU_USE_POSITIVE_POSIX_ERRORS else 1
-
-	@(private="file") _GENERAL_ERROR_BASE :: min(int)
-	@(private="file") _POSIX_ERROR_BASE   :: _GENERAL_ERROR_BASE + 0x7000
-
-	EDOM   :: _POSIX_ERROR_FACTOR * (_POSIX_ERROR_BASE + 16)
-	EILSEQ :: _POSIX_ERROR_FACTOR * (_POSIX_ERROR_BASE + 38)
-	ERANGE :: _POSIX_ERROR_FACTOR * (_POSIX_ERROR_BASE + 17)
-}
-
 when ODIN_OS == .JS {
 	_ :: libc
 	_get_errno :: proc "c" () -> ^int {
diff --git a/core/c/libc/locale.odin b/core/c/libc/locale.odin
index 3216e0f90..59cbc6c6d 100644
--- a/core/c/libc/locale.odin
+++ b/core/c/libc/locale.odin
@@ -110,7 +110,7 @@ when ODIN_OS == .Windows {
 	}
 }
 
-when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD  || ODIN_OS == .OpenBSD || ODIN_OS == .Haiku || ODIN_OS == .Windows {
+when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD  || ODIN_OS == .OpenBSD || ODIN_OS == .Windows {
 
 	LC_ALL      :: 0
 	LC_COLLATE  :: 1
diff --git a/core/c/libc/signal.odin b/core/c/libc/signal.odin
index cddf06916..cfe9768c9 100644
--- a/core/c/libc/signal.odin
+++ b/core/c/libc/signal.odin
@@ -34,7 +34,7 @@ when ODIN_OS == .Windows {
 	SIGTERM :: 15
 }
 
-when ODIN_OS == .Linux || ODIN_OS == .FreeBSD || ODIN_OS == .Haiku || ODIN_OS == .OpenBSD || ODIN_OS == .NetBSD || ODIN_OS == .Darwin {
+when ODIN_OS == .Linux || ODIN_OS == .FreeBSD || ODIN_OS == .OpenBSD || ODIN_OS == .NetBSD || ODIN_OS == .Darwin {
 	SIG_ERR  :: rawptr(~uintptr(0))
 	SIG_DFL  :: rawptr(uintptr(0))
 	SIG_IGN  :: rawptr(uintptr(1)) 
diff --git a/core/c/libc/stdio.odin b/core/c/libc/stdio.odin
index db5b202e7..ffdb06f67 100644
--- a/core/c/libc/stdio.odin
+++ b/core/c/libc/stdio.odin
@@ -200,36 +200,6 @@ when ODIN_OS == .Darwin {
 	}
 }
 
-when ODIN_OS == .Haiku {
-	fpos_t :: distinct i64
-	
-	_IOFBF        :: 0
-	_IOLBF        :: 1
-	_IONBF        :: 2
-
-	BUFSIZ        :: 8192
-
-	EOF           :: int(-1)
-
-	FOPEN_MAX     :: 128
-
-	FILENAME_MAX  :: 256
-
-	L_tmpnam      :: 512
-
-	SEEK_SET      :: 0
-	SEEK_CUR      :: 1
-	SEEK_END      :: 2
-
-	TMP_MAX       :: 32768
-
-	foreign libc {
-		stderr: ^FILE
-		stdin:  ^FILE
-		stdout: ^FILE
-	}
-}
-
 when ODIN_OS == .NetBSD {
 	@(private) LRENAME  :: "__posix_rename"
 	@(private) LFGETPOS :: "__fgetpos50"
diff --git a/core/c/libc/stdlib.odin b/core/c/libc/stdlib.odin
index ca906a5f0..f63f40cd0 100644
--- a/core/c/libc/stdlib.odin
+++ b/core/c/libc/stdlib.odin
@@ -42,22 +42,6 @@ when ODIN_OS == .Linux {
 	}
 }
 
-when ODIN_OS == .Haiku {
-	RAND_MAX :: 0x7fffffff
-
-	// GLIBC and MUSL only
-	@(private="file")
-	@(default_calling_convention="c")
-	foreign libc {
-		__ctype_get_mb_cur_max :: proc() -> ushort ---
-	}
-
-	MB_CUR_MAX :: #force_inline proc() -> size_t {
-		return size_t(__ctype_get_mb_cur_max())
-	}
-}
-
-
 when ODIN_OS == .Darwin || ODIN_OS == .FreeBSD || ODIN_OS == .OpenBSD {
 	RAND_MAX :: 0x7fffffff
 
diff --git a/core/c/libc/time.odin b/core/c/libc/time.odin
index 6106923f5..d431a84d7 100644
--- a/core/c/libc/time.odin
+++ b/core/c/libc/time.odin
@@ -45,7 +45,7 @@ when ODIN_OS == .Windows {
 	}
 }
 
-when ODIN_OS == .Linux || ODIN_OS == .FreeBSD || ODIN_OS == .Darwin || ODIN_OS == .OpenBSD || ODIN_OS == .NetBSD || ODIN_OS == .Haiku || ODIN_OS == .JS  {
+when ODIN_OS == .Linux || ODIN_OS == .FreeBSD || ODIN_OS == .Darwin || ODIN_OS == .OpenBSD || ODIN_OS == .NetBSD || ODIN_OS == .JS  {
 	@(default_calling_convention="c")
 	foreign libc {
 		// 7.27.2 Time manipulation functions
@@ -95,7 +95,7 @@ when ODIN_OS == .Linux || ODIN_OS == .FreeBSD || ODIN_OS == .Darwin || ODIN_OS =
 
 	time_t :: distinct i64
 
-	when ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD || ODIN_OS == .Haiku {
+	when ODIN_OS == .FreeBSD || ODIN_OS == .NetBSD {
 		clock_t :: distinct int32_t
 	} else {
 		clock_t :: distinct long
diff --git a/core/c/libc/wctype.odin b/core/c/libc/wctype.odin
index 6526a14e2..7d39e75c0 100644
--- a/core/c/libc/wctype.odin
+++ b/core/c/libc/wctype.odin
@@ -30,10 +30,6 @@ when ODIN_OS == .Windows {
 	wctrans_t :: distinct int
 	wctype_t  :: distinct ulong
 
-} else when ODIN_OS == .Haiku {
-	wctrans_t :: distinct i32
-	wctype_t  :: distinct i32
-
 }
 
 @(default_calling_convention="c")