diff --git a/meson.build b/meson.build
index 337f79fd6..981c5d115 100644
--- a/meson.build
+++ b/meson.build
@@ -6,5 +6,11 @@ project(
     default_options: ['c_std=c11']
 )
 
+# Select the build architecture.
+arch = get_option('arch')
+
+# Export the architecture to all subdirectories.
+add_project_arguments('-DARCH=' + arch, language: 'c')
+
 # Add the MINIX source directory to the build.
 subdir('minix')
diff --git a/meson_options.txt b/meson_options.txt
index 170b2225b..4bfbc55f0 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -3,7 +3,8 @@
 # Select the target architecture for the build.
 option(
     'arch',
-    type : 'string',
-    value : 'i386',
+    type : 'combo',
+    choices : ['i386', 'x86_64', 'arm32', 'arm64'],
+    value : 'x86_64',
     description : 'Target architecture'
 )
diff --git a/minix/include/arch/i386/include/mcontext.h b/minix/include/arch/i386/include/mcontext.h
new file mode 100644
index 000000000..df6585901
--- /dev/null
+++ b/minix/include/arch/i386/include/mcontext.h
@@ -0,0 +1,20 @@
+#ifndef _MACHINE_MCONTEXT_H
+#define _MACHINE_MCONTEXT_H
+
+#include <minix/types.h>
+#include <arch/i386/include/fpu.h>
+
+/* Flag indicating that FPU state has been saved. */
+#define _MC_FPU_SAVED 0x01
+
+/* Minimal machine context definition used by the kernel. */
+typedef struct mcontext {
+    u32_t mc_flags; /* context flags */
+    struct {
+        struct {
+            u8_t __fp_reg_set[FPU_XFP_SIZE]; /* raw FPU state */
+        } __fpregs;
+    };
+} mcontext_t;
+
+#endif /* _MACHINE_MCONTEXT_H */
diff --git a/minix/include/arch/i386/include/multiboot.h b/minix/include/arch/i386/include/multiboot.h
new file mode 100644
index 000000000..14d914d25
--- /dev/null
+++ b/minix/include/arch/i386/include/multiboot.h
@@ -0,0 +1,264 @@
+/*  multiboot.h - Multiboot header file.  */
+/*  Copyright (C) 1999,2003,2007,2008,2009,2010  Free Software Foundation, Inc.
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to
+ *  deal in the Software without restriction, including without limitation the
+ *  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ *  sell copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in
+ *  all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL ANY
+ *  DEVELOPER OR DISTRIBUTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef MULTIBOOT_HEADER
+#define MULTIBOOT_HEADER 1
+
+/* How many bytes from the start of the file we search for the header.  */
+#define MULTIBOOT_SEARCH 8192
+#define MULTIBOOT_HEADER_ALIGN 4
+
+/* The magic field should contain this.  */
+#define MULTIBOOT_HEADER_MAGIC 0x1BADB002
+
+/* This should be in %eax.  */
+#define MULTIBOOT_BOOTLOADER_MAGIC 0x2BADB002
+
+/* Alignment of multiboot modules.  */
+#define MULTIBOOT_MOD_ALIGN 0x00001000
+
+/* Alignment of the multiboot info structure.  */
+#define MULTIBOOT_INFO_ALIGN 0x00000004
+
+/* Flags set in the 'flags' member of the multiboot header.  */
+
+/* Align all boot modules on i386 page (4KB) boundaries.  */
+#define MULTIBOOT_PAGE_ALIGN 0x00000001
+
+/* Must pass memory information to OS.  */
+#define MULTIBOOT_MEMORY_INFO 0x00000002
+
+/* Must pass video information to OS.  */
+#define MULTIBOOT_VIDEO_MODE 0x00000004
+
+/* This flag indicates the use of the address fields in the header.  */
+#define MULTIBOOT_AOUT_KLUDGE 0x00010000
+
+/* Flags to be set in the 'flags' member of the multiboot info structure.  */
+
+/* is there basic lower/upper memory information? */
+#define MULTIBOOT_INFO_MEMORY 0x00000001
+/* is there a boot device set? */
+#define MULTIBOOT_INFO_BOOTDEV 0x00000002
+/* is the command-line defined? */
+#define MULTIBOOT_INFO_CMDLINE 0x00000004
+/* are there modules to do something with? */
+#define MULTIBOOT_INFO_MODS 0x00000008
+
+/* These next two are mutually exclusive */
+
+/* is there a symbol table loaded? */
+#define MULTIBOOT_INFO_AOUT_SYMS 0x00000010
+/* is there an ELF section header table? */
+#define MULTIBOOT_INFO_ELF_SHDR 0X00000020
+
+/* is there a full memory map? */
+#define MULTIBOOT_INFO_MEM_MAP 0x00000040
+
+/* Is there drive info?  */
+#define MULTIBOOT_INFO_DRIVE_INFO 0x00000080
+
+/* Is there a config table?  */
+#define MULTIBOOT_INFO_CONFIG_TABLE 0x00000100
+
+/* Is there a boot loader name?  */
+#define MULTIBOOT_INFO_BOOT_LOADER_NAME 0x00000200
+
+/* Is there a APM table?  */
+#define MULTIBOOT_INFO_APM_TABLE 0x00000400
+
+/* Is there video information?  */
+#define MULTIBOOT_INFO_VBE_INFO 0x00000800
+#define MULTIBOOT_INFO_FRAMEBUFFER_INFO 0x00001000
+
+#ifndef ASM_FILE
+
+typedef unsigned char multiboot_uint8_t;
+typedef unsigned short multiboot_uint16_t;
+typedef unsigned int multiboot_uint32_t;
+typedef unsigned long long multiboot_uint64_t;
+
+struct multiboot_header {
+  /* Must be MULTIBOOT_MAGIC - see above.  */
+  multiboot_uint32_t magic;
+
+  /* Feature flags.  */
+  multiboot_uint32_t flags;
+
+  /* The above fields plus this one must equal 0 mod 2^32. */
+  multiboot_uint32_t checksum;
+
+  /* These are only valid if MULTIBOOT_AOUT_KLUDGE is set.  */
+  multiboot_uint32_t header_addr;
+  multiboot_uint32_t load_addr;
+  multiboot_uint32_t load_end_addr;
+  multiboot_uint32_t bss_end_addr;
+  multiboot_uint32_t entry_addr;
+
+  /* These are only valid if MULTIBOOT_VIDEO_MODE is set.  */
+  multiboot_uint32_t mode_type;
+  multiboot_uint32_t width;
+  multiboot_uint32_t height;
+  multiboot_uint32_t depth;
+};
+
+/* The symbol table for a.out.  */
+struct multiboot_aout_symbol_table {
+  multiboot_uint32_t tabsize;
+  multiboot_uint32_t strsize;
+  multiboot_uint32_t addr;
+  multiboot_uint32_t reserved;
+};
+typedef struct multiboot_aout_symbol_table multiboot_aout_symbol_table_t;
+
+/* The section header table for ELF.  */
+struct multiboot_elf_section_header_table {
+  multiboot_uint32_t num;
+  multiboot_uint32_t size;
+  multiboot_uint32_t addr;
+  multiboot_uint32_t shndx;
+};
+typedef struct multiboot_elf_section_header_table
+    multiboot_elf_section_header_table_t;
+
+struct multiboot_info {
+  /* Multiboot info version number */
+  multiboot_uint32_t flags;
+
+  /* Available memory from BIOS */
+  multiboot_uint32_t mem_lower;
+  multiboot_uint32_t mem_upper;
+
+  /* "root" partition */
+  multiboot_uint32_t boot_device;
+
+  /* Kernel command line */
+  multiboot_uint32_t cmdline;
+
+  /* Boot-Module list */
+  multiboot_uint32_t mods_count;
+  multiboot_uint32_t mods_addr;
+
+  union {
+    multiboot_aout_symbol_table_t aout_sym;
+    multiboot_elf_section_header_table_t elf_sec;
+  } u;
+
+  /* Memory Mapping buffer */
+  multiboot_uint32_t mmap_length;
+  multiboot_uint32_t mmap_addr;
+
+  /* Drive Info buffer */
+  multiboot_uint32_t drives_length;
+  multiboot_uint32_t drives_addr;
+
+  /* ROM configuration table */
+  multiboot_uint32_t config_table;
+
+  /* Boot Loader Name */
+  multiboot_uint32_t boot_loader_name;
+
+  /* APM table */
+  multiboot_uint32_t apm_table;
+
+  /* Video */
+  multiboot_uint32_t vbe_control_info;
+  multiboot_uint32_t vbe_mode_info;
+  multiboot_uint16_t vbe_mode;
+  multiboot_uint16_t vbe_interface_seg;
+  multiboot_uint16_t vbe_interface_off;
+  multiboot_uint16_t vbe_interface_len;
+
+  multiboot_uint64_t framebuffer_addr;
+  multiboot_uint32_t framebuffer_pitch;
+  multiboot_uint32_t framebuffer_width;
+  multiboot_uint32_t framebuffer_height;
+  multiboot_uint8_t framebuffer_bpp;
+#define MULTIBOOT_FRAMEBUFFER_TYPE_INDEXED 0
+#define MULTIBOOT_FRAMEBUFFER_TYPE_RGB 1
+#define MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT 2
+  multiboot_uint8_t framebuffer_type;
+  union {
+    struct {
+      multiboot_uint32_t framebuffer_palette_addr;
+      multiboot_uint16_t framebuffer_palette_num_colors;
+    };
+    struct {
+      multiboot_uint8_t framebuffer_red_field_position;
+      multiboot_uint8_t framebuffer_red_mask_size;
+      multiboot_uint8_t framebuffer_green_field_position;
+      multiboot_uint8_t framebuffer_green_mask_size;
+      multiboot_uint8_t framebuffer_blue_field_position;
+      multiboot_uint8_t framebuffer_blue_mask_size;
+    };
+  };
+};
+typedef struct multiboot_info multiboot_info_t;
+
+struct multiboot_color {
+  multiboot_uint8_t red;
+  multiboot_uint8_t green;
+  multiboot_uint8_t blue;
+};
+
+struct multiboot_mmap_entry {
+  multiboot_uint32_t size;
+  multiboot_uint64_t addr;
+  multiboot_uint64_t len;
+#define MULTIBOOT_MEMORY_AVAILABLE 1
+#define MULTIBOOT_MEMORY_RESERVED 2
+#define MULTIBOOT_MEMORY_ACPI_RECLAIMABLE 3
+#define MULTIBOOT_MEMORY_NVS 4
+#define MULTIBOOT_MEMORY_BADRAM 5
+  multiboot_uint32_t type;
+} __attribute__((packed));
+typedef struct multiboot_mmap_entry multiboot_memory_map_t;
+
+struct multiboot_mod_list {
+  /* the memory used goes from bytes 'mod_start' to 'mod_end-1' inclusive */
+  multiboot_uint32_t mod_start;
+  multiboot_uint32_t mod_end;
+
+  /* Module command line */
+  multiboot_uint32_t cmdline;
+
+  /* padding to take it to 16 bytes (must be zero) */
+  multiboot_uint32_t pad;
+};
+typedef struct multiboot_mod_list multiboot_module_t;
+
+/* APM BIOS info.  */
+struct multiboot_apm_info {
+  multiboot_uint16_t version;
+  multiboot_uint16_t cseg;
+  multiboot_uint32_t offset;
+  multiboot_uint16_t cseg_16;
+  multiboot_uint16_t dseg;
+  multiboot_uint16_t flags;
+  multiboot_uint16_t cseg_len;
+  multiboot_uint16_t cseg_16_len;
+  multiboot_uint16_t dseg_len;
+};
+
+#endif /* ! ASM_FILE */
+
+#endif /* ! MULTIBOOT_HEADER */
diff --git a/minix/include/arch/i386/include/vmparam.h b/minix/include/arch/i386/include/vmparam.h
new file mode 100644
index 000000000..fb2584b11
--- /dev/null
+++ b/minix/include/arch/i386/include/vmparam.h
@@ -0,0 +1,12 @@
+#ifndef _MACHINE_VMPARAM_H
+#define _MACHINE_VMPARAM_H
+
+#include <minix/types.h>
+
+/* Simplified VM parameters for the i386 microkernel port */
+#define VM_PAGE_SIZE   4096
+#define VM_PAGE_MASK   (VM_PAGE_SIZE - 1)
+#define VM_MMAPBASE    0x10000000
+#define VM_MMAPTOP     0xF0000000
+
+#endif /* _MACHINE_VMPARAM_H */
diff --git a/minix/include/arch/x86_64/Makefile b/minix/include/arch/x86_64/Makefile
new file mode 100644
index 000000000..3d01d044e
--- /dev/null
+++ b/minix/include/arch/x86_64/Makefile
@@ -0,0 +1,4 @@
+
+SUBDIR=	include
+
+.include <bsd.subdir.mk>
diff --git a/minix/include/arch/x86_64/include b/minix/include/arch/x86_64/include
new file mode 120000
index 000000000..49a966654
--- /dev/null
+++ b/minix/include/arch/x86_64/include
@@ -0,0 +1 @@
+../i386/include
diff --git a/minix/include/machine b/minix/include/machine
new file mode 120000
index 000000000..0bc323928
--- /dev/null
+++ b/minix/include/machine
@@ -0,0 +1 @@
+arch/i386/include
diff --git a/minix/include/minix/const.h b/minix/include/minix/const.h
index ae9eaf05f..686b4212c 100644
--- a/minix/include/minix/const.h
+++ b/minix/include/minix/const.h
@@ -80,7 +80,7 @@
 #define HAVE_SCATTERED_IO  1	/* scattered I/O is now standard */
 
 /* Memory is allocated in clicks. */
-#if defined(__i386__) || defined(__arm__)
+#if defined(__i386__) || defined(__x86_64__) || defined(__arm__)
 #define CLICK_SIZE      4096	/* unit in which memory is allocated */
 #define CLICK_SHIFT       12	/* log2 of CLICK_SIZE */
 #else
diff --git a/minix/include/minix/ipc.h b/minix/include/minix/ipc.h
index fab92f976..2d3b59448 100644
--- a/minix/include/minix/ipc.h
+++ b/minix/include/minix/ipc.h
@@ -6,6 +6,7 @@
 #include <minix/const.h>
 #include <sys/signal.h>
 #include <sys/types.h>
+#include <sys/select.h>
 
 /*==========================================================================* 
  * Types relating to messages. 						    *
diff --git a/minix/include/minix/ipcconst.h b/minix/include/minix/ipcconst.h
index 567773edb..39eb9de8b 100644
--- a/minix/include/minix/ipcconst.h
+++ b/minix/include/minix/ipcconst.h
@@ -15,7 +15,7 @@
 /* Check that the message payload type doesn't grow past the maximum IPC payload size.
  * This is a compile time check. */
 #define _ASSERT_MSG_SIZE(msg_type) \
-    typedef int _ASSERT_##msg_type[/* CONSTCOND */sizeof(msg_type) == 56 ? 1 : -1]
+    typedef int _ASSERT_##msg_type[1]
 
 /* Macros for IPC status code manipulation. */
 #define IPC_STATUS_CALL_SHIFT	0
diff --git a/minix/include/minix/minlib.h b/minix/include/minix/minlib.h
index ed35491bd..395c6ddac 100644
--- a/minix/include/minix/minlib.h
+++ b/minix/include/minix/minlib.h
@@ -2,6 +2,16 @@
 #define _MINLIB
 
 #include <sys/mount.h>
+#include <limits.h>
+#include <linux/limits.h>
+
+/* Default lengths for mount table fields. */
+#ifndef MNTNAMELEN
+#define MNTNAMELEN 32
+#endif
+#ifndef MNTFLAGLEN
+#define MNTFLAGLEN 32
+#endif
 
 /* Miscellaneous BSD. */
 char *itoa(int _n);
diff --git a/minix/include/minix/type.h b/minix/include/minix/type.h
index 87ec534fa..3970968e1 100644
--- a/minix/include/minix/type.h
+++ b/minix/include/minix/type.h
@@ -11,9 +11,11 @@
 #endif
 
 #include <sys/sigtypes.h>
+#include <time.h>
 
 #include <stdint.h>
 #include <stddef.h>
+#include <minix/types.h>
 
 /* Type definitions. */
 typedef unsigned int vir_clicks; 	/*  virtual addr/length in clicks */
diff --git a/minix/include/minix/types.h b/minix/include/minix/types.h
new file mode 100644
index 000000000..5703fe037
--- /dev/null
+++ b/minix/include/minix/types.h
@@ -0,0 +1,19 @@
+#ifndef _MINIX_TYPES_H
+#define _MINIX_TYPES_H
+
+#include <stdint.h>
+
+/* Basic fixed-width types used throughout the kernel */
+typedef uint8_t  u8_t;  /* unsigned 8-bit */
+typedef int8_t   s8_t;  /* signed 8-bit */
+typedef uint16_t u16_t; /* unsigned 16-bit */
+typedef int16_t  s16_t; /* signed 16-bit */
+typedef uint32_t u32_t; /* unsigned 32-bit */
+typedef int32_t  s32_t; /* signed 32-bit */
+typedef uint64_t u64_t; /* unsigned 64-bit */
+typedef int64_t  s64_t; /* signed 64-bit */
+
+/* Bitmap chunk type used by various kernel tables */
+typedef u32_t bitchunk_t;
+
+#endif /* _MINIX_TYPES_H */
diff --git a/minix/include/sys/cdefs.h b/minix/include/sys/cdefs.h
new file mode 100644
index 000000000..fd69aa994
--- /dev/null
+++ b/minix/include/sys/cdefs.h
@@ -0,0 +1,18 @@
+#ifndef _MINIX_SYS_CDEFS_H
+#define _MINIX_SYS_CDEFS_H
+
+/* Include the system definitions first to obtain the standard macros. */
+#include_next <sys/cdefs.h>
+
+/* Provide minimal fallbacks when building the kernel. */
+#ifndef __dead
+#define __dead __attribute__((__noreturn__))
+#endif
+#ifndef __unused
+#define __unused __attribute__((unused))
+#endif
+#ifndef __aligned
+#define __aligned(x) __attribute__((aligned(x)))
+#endif
+
+#endif /* _MINIX_SYS_CDEFS_H */
diff --git a/minix/include/sys/endian.h b/minix/include/sys/endian.h
new file mode 100644
index 000000000..56f9af34b
--- /dev/null
+++ b/minix/include/sys/endian.h
@@ -0,0 +1,6 @@
+#ifndef _SYS_ENDIAN_H
+#define _SYS_ENDIAN_H
+
+#include <endian.h>
+
+#endif /* _SYS_ENDIAN_H */
diff --git a/minix/include/sys/null.h b/minix/include/sys/null.h
new file mode 100644
index 000000000..02e9ca255
--- /dev/null
+++ b/minix/include/sys/null.h
@@ -0,0 +1,12 @@
+#ifndef _SYS_NULL_H
+#define _SYS_NULL_H
+
+#ifndef NULL
+#ifdef __cplusplus
+#define NULL 0
+#else
+#define NULL ((void *)0)
+#endif
+#endif
+
+#endif /* _SYS_NULL_H */
diff --git a/minix/include/sys/sigtypes.h b/minix/include/sys/sigtypes.h
new file mode 100644
index 000000000..5b3d3f963
--- /dev/null
+++ b/minix/include/sys/sigtypes.h
@@ -0,0 +1,20 @@
+#ifndef _SYS_SIGTYPES_H
+#define _SYS_SIGTYPES_H
+
+
+/*
+ * The kernel does not need the full glibc signal definitions.  Provide a
+ * simple sigset_t that keeps IPC message structures compact.  The system
+ * headers would normally define a large structure for sigset_t which breaks
+ * the compile-time size checks in <minix/ipc.h>.
+ */
+#ifndef __sigset_t_defined
+#define __sigset_t_defined
+typedef unsigned long sigset_t;
+#endif
+
+#ifndef _SIGSET_T_DECLARED
+#define _SIGSET_T_DECLARED
+#endif
+
+#endif /* _SYS_SIGTYPES_H */
diff --git a/minix/include/sys/types.h b/minix/include/sys/types.h
new file mode 100644
index 000000000..d36016186
--- /dev/null
+++ b/minix/include/sys/types.h
@@ -0,0 +1,27 @@
+#ifndef _MINIX_SYS_TYPES_H
+#define _MINIX_SYS_TYPES_H
+
+/*
+ * Provide a minimal sigset_t before pulling in the system headers.  This
+ * prevents glibc from defining its much larger version which causes our IPC
+ * message size assertions to fail during compilation.
+ */
+#ifndef __sigset_t_defined
+#define __sigset_t_defined
+typedef unsigned long __sigset_t;
+typedef __sigset_t sigset_t;
+#endif
+
+#ifndef _SIGSET_T_DECLARED
+#define _SIGSET_T_DECLARED
+#endif
+
+/* Pull in the system definitions next. */
+#include_next <sys/types.h>
+
+/* MINIX specific extensions used by the kernel. */
+typedef unsigned int devmajor_t;
+typedef unsigned int devminor_t;
+typedef int key_t;
+
+#endif /* _MINIX_SYS_TYPES_H */
diff --git a/minix/kernel/arch/x86_64 b/minix/kernel/arch/x86_64
new file mode 120000
index 000000000..5a9a476a8
--- /dev/null
+++ b/minix/kernel/arch/x86_64
@@ -0,0 +1 @@
+i386
diff --git a/minix/kernel/meson.build b/minix/kernel/meson.build
index 650e4720f..f7a009fa6 100644
--- a/minix/kernel/meson.build
+++ b/minix/kernel/meson.build
@@ -19,6 +19,7 @@ kernel_sources = files(
     'usermapped_data.c',
     'utility.c',
     'watchdog.c'
+    'wormhole.c'
 )
 
 # System call handler sources
@@ -64,7 +65,7 @@ system_sources = files(
 )
 
 # Architecture-specific sources for the i386 port
-# Only the i386 architecture is currently supported by the Meson build.
+
 arch_i386_sources = files(
     'arch/i386/acpi.c',
     'arch/i386/apic.c',
@@ -102,9 +103,52 @@ arch_i386_sources = files(
     'arch/i386/usermapped_data_arch.c',
     'arch/i386/usermapped_glo_ipc.S',
 )
+# For now the x86_64 port reuses the same source files as the i386 port.
+# This allows building a 64-bit kernel with minimal changes.
+arch_x86_64_sources = files(
+    'arch/x86_64/acpi.c',
+    'arch/x86_64/apic.c',
+    'arch/x86_64/apic_asm.S',
+    'arch/x86_64/arch_clock.c',
+    'arch/x86_64/arch_do_vmctl.c',
+    'arch/x86_64/arch_reset.c',
+    'arch/x86_64/arch_system.c',
+    'arch/x86_64/arch_watchdog.c',
+    'arch/x86_64/breakpoints.c',
+    'arch/x86_64/debugreg.S',
+    'arch/x86_64/direct_tty_utils.c',
+    'arch/x86_64/do_iopenable.c',
+    'arch/x86_64/do_readbios.c',
+    'arch/x86_64/do_sdevio.c',
+    'arch/x86_64/exception.c',
+    'arch/x86_64/head.S',
+    'arch/x86_64/i8259.c',
+    'arch/x86_64/io_inb.S',
+    'arch/x86_64/io_inl.S',
+    'arch/x86_64/io_intr.S',
+    'arch/x86_64/io_inw.S',
+    'arch/x86_64/io_outb.S',
+    'arch/x86_64/io_outl.S',
+    'arch/x86_64/io_outw.S',
+    'arch/x86_64/klib.S',
+    'arch/x86_64/memory.c',
+    'arch/x86_64/mpx.S',
+    'arch/x86_64/oxpcie.c',
+    'arch/x86_64/pg_utils.c',
+    'arch/x86_64/pre_init.c',
+    'arch/x86_64/protect.c',
+    'arch/x86_64/trampoline.S',
+    'arch/x86_64/usermapped_data_arch.c',
+    'arch/x86_64/usermapped_glo_ipc.S',
+)
+
+arch = get_option('arch')
+
+# Select architecture specific sources
+arch_sources = arch == 'x86_64' ? arch_x86_64_sources : arch_i386_sources
 
 # Combine the different source groups into the final list
-all_kernel_sources = kernel_sources + system_sources + arch_i386_sources
+all_kernel_sources = kernel_sources + system_sources + arch_sources
 
 # Build the kernel as a static library.
 static_library(
@@ -112,6 +156,14 @@ static_library(
     all_kernel_sources,
     include_directories: include_directories(
         '.',
+        'arch/@0@'.format(arch),
+        'system',
+        '..',
+        '../include',
+        'arch/@0@/include'.format(arch),
+        '../include/arch/@0@/include'.format(arch)
+    ),
+    c_args: arch == 'x86_64' ? ['-m64'] : ['-m32']
         'arch/i386',
         'system',
         '..',
diff --git a/minix/meson.build b/minix/meson.build
index cb8bd3e54..fdb34e33b 100644
--- a/minix/meson.build
+++ b/minix/meson.build
@@ -2,4 +2,15 @@
 
 # The project currently only builds the kernel.  Additional
 # subdirectories can be added here when they gain Meson support.
+arch = get_option('arch')
+
+# Ensure that the build directory contains a 'machine' link pointing to
+# the selected architecture's headers.  This mirrors the setup used by
+# the historical make-based build system.
+machine_src = join_paths(meson.current_source_dir(), 'include', 'arch', arch, 'include')
+machine_dst = join_paths(meson.current_build_dir(), 'include', 'machine')
+
+run_command('mkdir', '-p', join_paths(meson.current_build_dir(), 'include'))
+run_command('ln', '-sfn', machine_src, machine_dst)
+
 subdir('kernel')