diff --git a/libc/malloc_debug/malloc_debug.h b/libc/malloc_debug/malloc_debug.h
new file mode 100644
index 0000000..4a15f77
--- /dev/null
+++ b/libc/malloc_debug/malloc_debug.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef MALLOC_DEBUG_H
+#define MALLOC_DEBUG_H
+
+#include <stdint.h>
+
+#include <private/bionic_malloc_dispatch.h>
+
+// Allocations that require a header include a variable length header.
+// This is the order that data structures will be found. If an optional
+// part of the header does not exist, the other parts of the header
+// will still be in this order.
+//   Header          (Required)
+//   BacktraceHeader (Optional: For the allocation backtrace)
+//   BacktraceHeader (Optional: For the free backtrace)
+//   uint8_t data    (Optional: Front guard, will be a multiple of sizeof(uintptr_t))
+//   allocation data
+//   uint8_t data    (Optional: End guard)
+//
+// If backtracing is enabled, then both BacktraceHeaders will be present.
+//
+// In the initialization function, offsets into the header will be set
+// for each different header location. The offsets are always from the
+// beginning of the Header section.
+struct Header {
+  uint32_t tag;
+  void* orig_pointer;
+  size_t size;
+  size_t usable_size;
+  size_t real_size() const { return size & ~(1U << 31); }
+  void set_zygote() { size |= 1U << 31; }
+  static size_t max_size() { return (1U << 31) - 1; }
+} __attribute__((packed));
+
+struct TrackHeader {
+  Header* prev = nullptr;
+  Header* next = nullptr;
+} __attribute__((packed));
+
+struct BacktraceHeader {
+  size_t num_frames;
+  uintptr_t frames[0];
+} __attribute__((packed));
+
+constexpr uint32_t DEBUG_TAG = 0x1ee7d00d;
+constexpr char LOG_DIVIDER[] = "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***";
+constexpr size_t FREE_TRACK_MEM_BUFFER_SIZE = 4096;
+
+extern const MallocDispatch* g_dispatch;
+
+#endif // MALLOC_DEBUG_H