diff --git a/.arclint b/.arclint
index 5aa9156ae..587cf5150 100644
--- a/.arclint
+++ b/.arclint
@@ -1,254 +1,259 @@
 {
     "linters": {
         "generated": {
             "type": "generated"
         },
         "clang-format": {
             "type": "clang-format",
             "version": ">=8.0",
             "bin": ["clang-format-8", "clang-format"],
             "include": "(^src/.*\\.(h|c|cpp|mm)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "autopep8": {
             "type": "autopep8",
             "version": ">=1.3.4",
             "include": "(\\.py$)",
             "exclude": [
-                "(^contrib/gitian-builder/)"
+                "(^contrib/gitian-builder/)",
+                "(^contrib/apple-sdk-tools/)"
             ],
             "flags": [
                 "--aggressive",
                 "--ignore=W503,W504"
             ]
         },
         "flake8": {
             "type": "flake8",
             "version": ">=3.0",
             "include": "(\\.py$)",
             "exclude": [
-                "(^contrib/gitian-builder/)"
+                "(^contrib/gitian-builder/)",
+                "(^contrib/apple-sdk-tools/)"
             ],
             "flags": [
                 "--ignore=E501,E704,W503,W504"
             ]
         },
         "lint-format-strings": {
             "type": "lint-format-strings",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "check-doc": {
             "type": "check-doc",
             "include": "(^src/.*\\.(h|c|cpp)$)"
         },
         "lint-tests": {
             "type": "lint-tests",
             "include": "(^src/(seeder/|rpc/|wallet/)?test/.*\\.(cpp)$)"
         },
         "lint-python-format": {
             "type": "lint-python-format",
             "include": "(\\.py$)",
             "exclude": [
                 "(^test/lint/lint-python-format\\.py$)",
-                "(^contrib/gitian-builder/)"
+                "(^contrib/gitian-builder/)",
+                "(^contrib/apple-sdk-tools/)"
             ]
         },
         "phpcs": {
             "type": "phpcs",
             "include": "(\\.php$)",
             "exclude": [
                 "(^arcanist/__phutil_library_.+\\.php$)"
             ],
             "phpcs.standard": "arcanist/phpcs.xml"
         },
         "lint-locale-dependence": {
             "type": "lint-locale-dependence",
             "include": "(^src/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/(crypto/ctaes/|leveldb/|secp256k1/|tinyformat.h|univalue/))"
             ]
         },
         "lint-cheader": {
             "type": "lint-cheader",
             "include": "(^src/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/(crypto/ctaes|secp256k1|univalue|leveldb)/)"
             ]
         },
         "spelling": {
             "type": "spelling",
             "exclude": [
                 "(^build-aux/m4/)",
                 "(^depends/)",
                 "(^doc/release-notes/)",
                 "(^contrib/gitian-builder/)",
                 "(^src/(qt/locale|secp256k1|univalue|leveldb)/)",
                 "(^test/lint/dictionary/)"
             ],
             "spelling.dictionaries": [
                 "test/lint/dictionary/english.json"
             ]
         },
         "lint-assert-with-side-effects": {
             "type": "lint-assert-with-side-effects",
             "include": "(^src/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-include-quotes": {
             "type": "lint-include-quotes",
             "include": "(^src/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-include-guard": {
             "type": "lint-include-guard",
             "include": "(^src/.*\\.h$)",
             "exclude": [
                 "(^src/(crypto/ctaes|secp256k1|univalue|leveldb)/)",
                 "(^src/tinyformat.h$)"
             ]
         },
         "lint-include-source": {
             "type": "lint-include-source",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-stdint": {
             "type": "lint-stdint",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)",
                 "(^src/compat/assumptions.h$)"
             ]
         },
         "lint-source-filename": {
             "type": "lint-source-filename",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-boost-dependencies": {
             "type": "lint-boost-dependencies",
             "include": "(^src/.*\\.(h|cpp)$)"
         },
         "check-rpc-mappings": {
             "type": "check-rpc-mappings",
             "include": "(^src/(rpc/|wallet/rpc).*\\.cpp$)"
         },
         "lint-python-encoding": {
             "type": "lint-python-encoding",
             "include": "(\\.py$)",
             "exclude": [
-                "(^contrib/gitian-builder/)"
+                "(^contrib/gitian-builder/)",
+                "(^contrib/apple-sdk-tools/)"
             ]
         },
         "lint-python-shebang": {
             "type": "lint-python-shebang",
             "include": "(\\.py$)",
             "exclude": [
                 "(__init__\\.py$)",
-                "(^contrib/gitian-builder/)"
+                "(^contrib/gitian-builder/)",
+                "(^contrib/apple-sdk-tools/)"
             ]
         },
         "lint-bash-shebang": {
             "type": "lint-bash-shebang",
             "include": "(\\.sh$)",
             "exclude": [
                 "(^contrib/gitian-builder/)"
             ]
         },
         "shellcheck": {
             "type": "shellcheck",
             "version": ">=0.7.0",
             "flags": [
                 "--external-sources",
                 "--source-path=SCRIPTDIR"
             ],
             "include": "(\\.sh$)",
             "exclude": [
                 "(^contrib/gitian-builder/)",
                 "(^src/(secp256k1|univalue)/)"
             ]
         },
         "lint-shell-locale": {
             "type": "lint-shell-locale",
             "include": "(\\.sh$)",
             "exclude": [
                 "(^contrib/gitian-builder/)",
                 "(^src/(secp256k1|univalue)/)",
                 "(^cmake/utils/log-and-print-on-failure.sh)"
             ]
         },
         "lint-cpp-void-parameters": {
             "type": "lint-cpp-void-parameters",
             "include": "(^src/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/(crypto/ctaes|secp256k1|univalue|leveldb)/)",
                 "(^src/compat/glibc_compat.cpp$)"
             ]
         },
         "lint-logs": {
             "type": "lint-logs",
             "include": "(^src/.*\\.(h|cpp)$)"
         },
         "lint-qt": {
             "type": "lint-qt",
             "include": "(^src/qt/.*\\.(h|cpp)$)",
             "exclude": [
                 "(^src/qt/(locale|forms|res)/)"
             ]
         },
         "lint-doxygen": {
             "type": "lint-doxygen",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(crypto/ctaes|secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-whitespace": {
             "type": "lint-whitespace",
             "include": "(\\.(ac|am|cmake|conf|in|include|json|m4|md|openrc|php|pl|sh|txt|yml)$)",
             "exclude": [
                 "(^contrib/gitian-builder/)",
                 "(^src/(secp256k1|univalue|leveldb)/)"
             ]
         },
         "lint-cppcheck": {
             "type": "lint-cppcheck",
             "include": "(^src/.*\\.(h|c|cpp)$)",
             "exclude": [
                 "(^src/(crypto/ctaes|secp256k1|univalue|leveldb)/)"
             ]
         },
         "yamllint": {
             "type": "yamllint",
             "include": "(\\.(yml|yaml)$)"
         },
         "lint-check-nonfatal": {
             "type": "lint-check-nonfatal",
             "include": [
                 "(^src/rpc/.*\\.(h|c|cpp)$)",
                 "(^src/wallet/rpc*.*\\.(h|c|cpp)$)"
             ],
             "exclude": "(^src/rpc/server.cpp)"
         },
         "lint-markdown": {
             "type": "lint-markdown",
             "include": [
                 "(\\.md$)"
             ],
             "exclude": "(^contrib/gitian-builder/)"
         }
     }
 }
diff --git a/cmake/platforms/OSX.cmake b/cmake/platforms/OSX.cmake
index 92878c9ac..ab60e9ad1 100644
--- a/cmake/platforms/OSX.cmake
+++ b/cmake/platforms/OSX.cmake
@@ -1,45 +1,52 @@
 # Copyright (c) 2017 The Bitcoin developers
 
 set(CMAKE_SYSTEM_NAME Darwin)
 set(CMAKE_SYSTEM_PROCESSOR x86_64)
 set(TOOLCHAIN_PREFIX ${CMAKE_SYSTEM_PROCESSOR}-apple-darwin16)
 
 # On OSX, we use clang by default.
 set(CMAKE_C_COMPILER clang)
 set(CMAKE_CXX_COMPILER clang++)
 
 set(CMAKE_C_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
 set(CMAKE_CXX_COMPILER_TARGET ${TOOLCHAIN_PREFIX})
 
+set(OSX_MIN_VERSION 10.12)
+# OSX_SDK_VERSION 10.15.1
+# Note: don't use XCODE_VERSION, it's a cmake built-in variable !
+set(SDK_XCODE_VERSION 11.3.1)
+set(SDK_XCODE_BUILD_ID 11C505)
+set(LD64_VERSION 530)
+
 # On OSX we use various stuff from Apple's SDK.
-set(OSX_SDK_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/SDKs/MacOSX10.14.sdk")
-set(CMAKE_OSX_SYSROOT ${OSX_SDK_PATH})
-set(CMAKE_OSX_DEPLOYMENT_TARGET 10.12)
+set(OSX_SDK_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/SDKs/Xcode-${SDK_XCODE_VERSION}-${SDK_XCODE_BUILD_ID}-extracted-SDK-with-libcxx-headers")
+set(CMAKE_OSX_SYSROOT "${OSX_SDK_PATH}")
+set(CMAKE_OSX_DEPLOYMENT_TARGET ${OSX_MIN_VERSION})
 set(CMAKE_OSX_ARCHITECTURES x86_64)
 
 # target environment on the build host system
 #   set 1st to dir with the cross compiler's C/C++ headers/libs
 set(CMAKE_FIND_ROOT_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX};${OSX_SDK_PATH}")
 
 # We also may have built dependencies for the native plateform.
 set(CMAKE_PREFIX_PATH "${CMAKE_CURRENT_SOURCE_DIR}/depends/${TOOLCHAIN_PREFIX}/native")
 
 # modify default behavior of FIND_XXX() commands to
 # search for headers/libs in the target environment and
 # search for programs in the build host environment
 set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
 set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
 set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
 
-string(APPEND CMAKE_CXX_FLAGS_INIT " -stdlib=libc++")
+string(APPEND CMAKE_CXX_FLAGS_INIT " -stdlib=libc++ -mlinker-version=${LD64_VERSION}")
 
 # Ensure we use an OSX specific version the binary manipulation tools.
 find_program(CMAKE_AR ${TOOLCHAIN_PREFIX}-ar)
 find_program(CMAKE_INSTALL_NAME_TOOL ${TOOLCHAIN_PREFIX}-install_name_tool)
 find_program(CMAKE_LINKER ${TOOLCHAIN_PREFIX}-ld)
 find_program(CMAKE_NM ${TOOLCHAIN_PREFIX}-nm)
 find_program(CMAKE_OBJCOPY ${TOOLCHAIN_PREFIX}-objcopy)
 find_program(CMAKE_OBJDUMP ${TOOLCHAIN_PREFIX}-objdump)
 find_program(CMAKE_OTOOL ${TOOLCHAIN_PREFIX}-otool)
 find_program(CMAKE_RANLIB ${TOOLCHAIN_PREFIX}-ranlib)
 find_program(CMAKE_STRIP ${TOOLCHAIN_PREFIX}-strip)
diff --git a/contrib/apple-sdk-tools/LICENSE b/contrib/apple-sdk-tools/LICENSE
new file mode 100644
index 000000000..4399763fe
--- /dev/null
+++ b/contrib/apple-sdk-tools/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 The Bitcoin Core developers
+
+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 THE
+AUTHORS OR COPYRIGHT HOLDERS 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.
diff --git a/contrib/apple-sdk-tools/README.md b/contrib/apple-sdk-tools/README.md
new file mode 100644
index 000000000..85197ccb5
--- /dev/null
+++ b/contrib/apple-sdk-tools/README.md
@@ -0,0 +1,17 @@
+Simple script(s) to extract from XCode .xip files.
+
+These files are simple enough to extract in simple python without dragging in
+dependencies.
+
+This is a working POC. The code is sloppy and there is very little error
+handling, but it works for all files tested.
+
+It contains a very simple python port of [pbzx](https://github.com/NiklasRosenstein/pbzx), thank you to NiklasRosenstein
+and PHPdev32.
+
+### Usage:
+./extract_xcode.py -f Xcode_*.xip | cpio -d -i
+
+### Maintainer Wanted
+
+Please feel free to fork and rewrite it into a more generally useful tool.
diff --git a/contrib/apple-sdk-tools/extract_xcode.py b/contrib/apple-sdk-tools/extract_xcode.py
new file mode 100755
index 000000000..6156b8c52
--- /dev/null
+++ b/contrib/apple-sdk-tools/extract_xcode.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+# Copyright (c) 2020 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+"""XCode extractor
+"""
+
+import argparse
+import sys
+import struct
+import zlib
+import xml.etree.ElementTree as ET
+import lzma
+
+XAR_MAGIC = b'\x78\x61\x72\x21'
+PBZX_MAGIC = b'\x70\x62\x7a\x78'
+LZMA_MAGIC = b'\xfd\x37\x7a\x58\x5a\x00'
+
+class io_wrapper(object):
+    """Helper for stdin/stdout binary weirdness"""
+    def __init__(self, filename, mode):
+        self.filename = filename
+        self.mode = mode
+    def __enter__(self):
+        if self.filename == '-':
+            if self.mode is None or self.mode == '' or 'r' in self.mode:
+                self.fh = sys.stdin
+            else:
+                self.fh = sys.stdout
+        else:
+            self.fh = open(self.filename, self.mode)
+        return self
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        if self.filename != '-':
+            self.fh.close()
+    def write(self, bytes):
+        if self.filename != '-':
+            return self.fh.write(bytes)
+        return self.fh.buffer.write(bytes)
+    def read(self, size):
+        if self.filename != '-':
+            return self.fh.read(size)
+        return self.fh.buffer.read(size)
+    def seek(self, size):
+        return self.fh.seek(size)
+
+def run():
+    parser = argparse.ArgumentParser(
+        description=__doc__, formatter_class=argparse.RawTextHelpFormatter)
+
+    parser.add_argument("-f", '--file', nargs='?', default="-")
+    parser.add_argument('outfile', nargs='?', default="-")
+
+    args = parser.parse_args()
+
+    with io_wrapper(args.file, "rb") as infile, io_wrapper(args.outfile, "wb") as outfile:
+
+        start_offset = 0
+        magic = infile.read(4)
+        if magic != XAR_MAGIC:
+            print("bad xar magic", file=sys.stderr)
+            sys.exit(1)
+
+        bytes = infile.read(24)
+        header_size, xar_version, toc_compressed, toc_uncompressed, checksum_type = struct.unpack('>HHQQI', bytes)
+        start_offset += header_size
+        start_offset += toc_compressed
+        bytes = infile.read(toc_compressed)
+
+        xml_toc = zlib.decompress(bytes).decode("utf-8") 
+
+        root = ET.fromstring(xml_toc)
+
+        content_offset = 0
+        content_length = 0
+        content_encoding = ""
+
+        toc = root.find("toc")
+        for elem in toc.findall("file"):
+            name = elem.find("name").text
+            if name == "Content":
+                data = elem.find("data")
+                content_offset = int(data.find("offset").text)
+                content_length = int(data.find("length").text)
+                content_encoding = data.find("encoding").get("style")
+                content_uncompressed_length = int(data.find("size").text)
+                found_content = True
+                break
+
+        if (content_length == 0):
+            print("No \"Content\" file to extract.", file=sys.stderr)
+            sys.exit(1)
+
+        infile.seek(content_offset + start_offset)
+
+        content_read_size = 0
+
+        magic = infile.read(4)
+        content_read_size += 4
+        if magic != PBZX_MAGIC:
+            print("bad pbzx magic", file=sys.stderr)
+            sys.exit(2)
+
+        bytes = infile.read(8)
+        content_read_size += 8
+        flags, = struct.unpack('>Q', bytes)
+        bytes = infile.read(16)
+        content_read_size += 16
+        while (flags & 1 << 24):
+            flags, size = struct.unpack('>QQ', bytes)
+            bytes = infile.read(size)
+            content_read_size += size
+            compressed = size != 1 << 24
+            if compressed:
+                if bytes[0:6] != LZMA_MAGIC:
+                    print("bad lzma magic: ", file=sys.stderr)
+                    sys.exit(3)
+                outfile.write(lzma.decompress(bytes))
+            else:
+                outfile.write(bytes)
+
+            if content_read_size == content_length:
+                break
+                
+            bytes = infile.read(16)
+            content_read_size += 16
+
+if __name__ == '__main__':
+    run()
diff --git a/contrib/gitian-build.py b/contrib/gitian-build.py
index 09ab63ac8..fc86239e6 100755
--- a/contrib/gitian-build.py
+++ b/contrib/gitian-build.py
@@ -1,312 +1,312 @@
 #!/usr/bin/env python3
 
 import argparse
 import multiprocessing
 import os
 import subprocess
 import sys
 
 
 def setup():
     global args, workdir
     programs = ['ruby', 'git', 'apt-cacher-ng', 'make', 'wget']
     if args.kvm:
         programs += ['python-vm-builder', 'qemu-kvm', 'qemu-utils']
     elif args.docker:
         dockers = ['docker.io', 'docker-ce']
         for i in dockers:
             return_code = subprocess.call(
                 ['sudo', 'apt-get', 'install', '-qq', i])
             if return_code == 0:
                 break
         if return_code != 0:
             print('Cannot find any way to install docker', file=sys.stderr)
             exit(1)
     else:
         programs += ['lxc', 'debootstrap']
     subprocess.check_call(['sudo', 'apt-get', 'install', '-qq'] + programs)
     if not os.path.isdir('gitian-builder'):
         subprocess.check_call(
             ['git', 'clone', 'https://github.com/devrandom/gitian-builder.git'])
     if not os.path.isdir('bitcoin-abc'):
         subprocess.check_call(
             ['git', 'clone', 'https://github.com/Bitcoin-ABC/bitcoin-abc.git'])
     os.chdir('gitian-builder')
     make_image_prog = ['bin/make-base-vm',
                        '--distro', 'debian', '--suite', 'buster', '--arch', 'amd64']
     if args.docker:
         make_image_prog += ['--docker']
     elif not args.kvm:
         make_image_prog += ['--lxc']
     subprocess.check_call(make_image_prog)
     os.chdir(workdir)
     if args.is_bionic and not args.kvm and not args.docker:
         subprocess.check_call(
             ['sudo', 'sed', '-i', 's/lxcbr0/br0/', '/etc/default/lxc-net'])
         print('Reboot is required')
         exit(0)
 
 
 def build():
     global args, workdir
 
     base_output_dir = 'bitcoin-binaries/' + args.version
     os.makedirs(base_output_dir + '/src', exist_ok=True)
     print('\nBuilding Dependencies\n')
     os.chdir('gitian-builder')
     os.makedirs('inputs', exist_ok=True)
 
     subprocess.check_call(['make', '-C', '../bitcoin-abc/depends',
                            'download', 'SOURCES_PATH=' + os.getcwd() + '/cache/common'])
 
     output_dir_src = '../' + base_output_dir + '/src'
     if args.linux:
         print('\nCompiling ' + args.version + ' Linux')
         subprocess.check_call(['bin/gbuild', '-j', args.jobs, '-m', args.memory, '--commit', 'bitcoin=' + args.commit,
                                '--url', 'bitcoin=' + args.url, '../bitcoin-abc/contrib/gitian-descriptors/gitian-linux.yml'])
         subprocess.check_call(['bin/gsign', '-p', args.sign_prog, '--signer', args.signer, '--release', args.version +
                                '-linux', '--destination', '../gitian.sigs/', '../bitcoin-abc/contrib/gitian-descriptors/gitian-linux.yml'])
         output_dir_linux = '../' + base_output_dir + '/linux'
         os.makedirs(output_dir_linux, exist_ok=True)
         subprocess.check_call(
             'mv build/out/bitcoin-*.tar.gz ' + output_dir_linux, shell=True)
         subprocess.check_call(
             'mv build/out/src/bitcoin-*.tar.gz ' + output_dir_src, shell=True)
         subprocess.check_call(
             'mv result/bitcoin-*-linux-res.yml ' + output_dir_linux, shell=True)
 
     if args.windows:
         print('\nCompiling ' + args.version + ' Windows')
         subprocess.check_call(['bin/gbuild', '-j', args.jobs, '-m', args.memory, '--commit', 'bitcoin=' + args.commit,
                                '--url', 'bitcoin=' + args.url, '../bitcoin-abc/contrib/gitian-descriptors/gitian-win.yml'])
         subprocess.check_call(['bin/gsign', '-p', args.sign_prog, '--signer', args.signer, '--release', args.version +
                                '-win-unsigned', '--destination', '../gitian.sigs/', '../bitcoin-abc/contrib/gitian-descriptors/gitian-win.yml'])
         output_dir_win = '../' + base_output_dir + '/win'
         os.makedirs(output_dir_win, exist_ok=True)
         subprocess.check_call(
             'mv build/out/bitcoin-*-win-unsigned.tar.gz inputs/', shell=True)
         subprocess.check_call(
             'mv build/out/bitcoin-*.zip build/out/bitcoin-*.exe ' + output_dir_win, shell=True)
         subprocess.check_call(
             'mv build/out/src/bitcoin-*.tar.gz ' + output_dir_src, shell=True)
         subprocess.check_call(
             'mv result/bitcoin-*-win-res.yml ' + output_dir_win, shell=True)
 
     if args.macos:
         print('\nCompiling ' + args.version + ' MacOS')
         subprocess.check_call(['bin/gbuild', '-j', args.jobs, '-m', args.memory, '--commit', 'bitcoin=' + args.commit,
                                '--url', 'bitcoin=' + args.url, '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx.yml'])
         subprocess.check_call(['bin/gsign', '-p', args.sign_prog, '--signer', args.signer, '--release', args.version +
                                '-osx-unsigned', '--destination', '../gitian.sigs/', '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx.yml'])
         output_dir_osx = '../' + base_output_dir + '/osx'
         os.makedirs(output_dir_osx, exist_ok=True)
         subprocess.check_call(
             'mv build/out/bitcoin-*-osx-unsigned.tar.gz inputs/', shell=True)
         subprocess.check_call(
             'mv build/out/bitcoin-*.tar.gz build/out/bitcoin-*.dmg ' + output_dir_osx, shell=True)
         subprocess.check_call(
             'mv build/out/src/bitcoin-*.tar.gz ' + output_dir_src, shell=True)
         subprocess.check_call(
             'mv result/bitcoin-*-osx-res.yml ' + output_dir_osx, shell=True)
 
     os.chdir(workdir)
 
     if args.commit_files:
         print('\nCommitting ' + args.version + ' Unsigned Sigs\n')
         os.chdir('gitian.sigs')
         subprocess.check_call(
             ['git', 'add', args.version + '-linux/' + args.signer])
         subprocess.check_call(
             ['git', 'add', args.version + '-win-unsigned/' + args.signer])
         subprocess.check_call(
             ['git', 'add', args.version + '-osx-unsigned/' + args.signer])
         subprocess.check_call(
             ['git', 'commit', '-m', 'Add ' + args.version + ' unsigned sigs for ' + args.signer])
         os.chdir(workdir)
 
 
 def sign():
     global args, workdir
     os.chdir('gitian-builder')
 
     if args.windows:
         print('\nSigning ' + args.version + ' Windows')
         subprocess.check_call('cp inputs/bitcoin-' + args.version +
                               '-win-unsigned.tar.gz inputs/bitcoin-win-unsigned.tar.gz', shell=True)
         subprocess.check_call(['bin/gbuild', '-i', '--commit', 'signature=' + args.commit,
                                '../bitcoin-abc/contrib/gitian-descriptors/gitian-win-signer.yml'])
         subprocess.check_call(['bin/gsign', '-p', args.sign_prog, '--signer', args.signer, '--release', args.version + '-win-signed',
                                '--destination', '../gitian.sigs/', '../bitcoin-abc/contrib/gitian-descriptors/gitian-win-signer.yml'])
         subprocess.check_call(
             'mv build/out/bitcoin-*win64-setup.exe ../bitcoin-binaries/' + args.version, shell=True)
 
     if args.macos:
         print('\nSigning ' + args.version + ' MacOS')
         subprocess.check_call('cp inputs/bitcoin-' + args.version +
                               '-osx-unsigned.tar.gz inputs/bitcoin-osx-unsigned.tar.gz', shell=True)
         subprocess.check_call(['bin/gbuild', '-i', '--commit', 'signature=' + args.commit,
                                '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx-signer.yml'])
         subprocess.check_call(['bin/gsign', '-p', args.sign_prog, '--signer', args.signer, '--release', args.version + '-osx-signed',
                                '--destination', '../gitian.sigs/', '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx-signer.yml'])
         subprocess.check_call('mv build/out/bitcoin-osx-signed.dmg ../bitcoin-binaries/' +
                               args.version + '/bitcoin-' + args.version + '-osx.dmg', shell=True)
 
     os.chdir(workdir)
 
     if args.commit_files:
         print('\nCommitting ' + args.version + ' Signed Sigs\n')
         os.chdir('gitian.sigs')
         subprocess.check_call(
             ['git', 'add', args.version + '-win-signed/' + args.signer])
         subprocess.check_call(
             ['git', 'add', args.version + '-osx-signed/' + args.signer])
         subprocess.check_call(['git', 'commit', '-a', '-m', 'Add ' +
                                args.version + ' signed binary sigs for ' + args.signer])
         os.chdir(workdir)
 
 
 def verify():
     global args, workdir
     os.chdir('gitian-builder')
 
     print('\nVerifying v' + args.version + ' Linux\n')
     subprocess.check_call(['bin/gverify', '-v', '-d', '../gitian.sigs/', '-r', args.version +
                            '-linux', '../bitcoin-abc/contrib/gitian-descriptors/gitian-linux.yml'])
     print('\nVerifying v' + args.version + ' Windows\n')
     subprocess.check_call(['bin/gverify', '-v', '-d', '../gitian.sigs/', '-r', args.version +
                            '-win-unsigned', '../bitcoin-abc/contrib/gitian-descriptors/gitian-win.yml'])
     print('\nVerifying v' + args.version + ' MacOS\n')
     subprocess.check_call(['bin/gverify', '-v', '-d', '../gitian.sigs/', '-r', args.version +
                            '-osx-unsigned', '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx.yml'])
     print('\nVerifying v' + args.version + ' Signed Windows\n')
     subprocess.check_call(['bin/gverify', '-v', '-d', '../gitian.sigs/', '-r', args.version +
                            '-win-signed', '../bitcoin-abc/contrib/gitian-descriptors/gitian-win-signer.yml'])
     print('\nVerifying v' + args.version + ' Signed MacOS\n')
     subprocess.check_call(['bin/gverify', '-v', '-d', '../gitian.sigs/', '-r', args.version +
                            '-osx-signed', '../bitcoin-abc/contrib/gitian-descriptors/gitian-osx-signer.yml'])
 
     os.chdir(workdir)
 
 
 def main():
     global args, workdir
     num_cpus = multiprocessing.cpu_count()
 
     parser = argparse.ArgumentParser(usage='%(prog)s [options] signer version')
     parser.add_argument('-c', '--commit', action='store_true', dest='commit',
                         help='Indicate that the version argument is for a commit or branch')
     parser.add_argument('-p', '--pull', action='store_true', dest='pull',
                         help='Indicate that the version argument is the number of a github repository pull request')
     parser.add_argument('-u', '--url', dest='url', default='https://github.com/Bitcoin-ABC/bitcoin-abc.git',
                         help='Specify the URL of the repository. Default is %(default)s')
     parser.add_argument('-v', '--verify', action='store_true',
                         dest='verify', help='Verify the Gitian build')
     parser.add_argument('-b', '--build', action='store_true',
                         dest='build', help='Do a Gitian build')
     parser.add_argument('-s', '--sign', action='store_true', dest='sign',
                         help='Make signed binaries for Windows and MacOS')
     parser.add_argument('-B', '--buildsign', action='store_true',
                         dest='buildsign', help='Build both signed and unsigned binaries')
     parser.add_argument('-o', '--os', dest='os', default='lwm',
                         help='Specify which Operating Systems the build is for. Default is %(default)s. l for Linux, w for Windows, m for MacOS')
     parser.add_argument('-j', '--jobs', dest='jobs', default=str(num_cpus),
                         help='Number of processes to use. Default %(default)s')
     parser.add_argument('-m', '--memory', dest='memory', default='3500',
                         help='Memory to allocate in MiB. Default %(default)s')
     parser.add_argument('-k', '--kvm', action='store_true',
                         dest='kvm', help='Use KVM instead of LXC')
     parser.add_argument('-d', '--docker', action='store_true',
                         dest='docker', help='Use Docker instead of LXC')
     parser.add_argument('-S', '--setup', action='store_true', dest='setup',
                         help='Set up the Gitian building environment. Uses LXC. If you want to use KVM, use the --kvm option. Only works on Debian-based systems (Ubuntu, Debian)')
     parser.add_argument('-D', '--detach-sign', action='store_true', dest='detach_sign',
                         help='Create the assert file for detached signing. Will not commit anything.')
     parser.add_argument('-n', '--no-commit', action='store_false',
                         dest='commit_files', help='Do not commit anything to git')
     parser.add_argument(
         'signer', help='GPG signer to sign each build assert file')
     parser.add_argument(
         'version', help='Version number, commit, or branch to build. If building a commit or branch, the -c option must be specified')
 
     args = parser.parse_args()
     workdir = os.getcwd()
 
     args.linux = 'l' in args.os
     args.windows = 'w' in args.os
     args.macos = 'm' in args.os
 
     args.is_bionic = b'bionic' in subprocess.check_output(
         ['lsb_release', '-cs'])
 
     if args.buildsign:
         args.build = True
         args.sign = True
 
     if args.kvm and args.docker:
         raise Exception('Error: cannot have both kvm and docker')
 
     args.sign_prog = 'true' if args.detach_sign else 'gpg --detach-sign'
 
     # Set environment variable USE_LXC or USE_DOCKER, let gitian-builder know
     # that we use lxc or docker
     if args.docker:
         os.environ['USE_DOCKER'] = '1'
     elif not args.kvm:
         os.environ['USE_LXC'] = '1'
         if 'GITIAN_HOST_IP' not in os.environ.keys():
             os.environ['GITIAN_HOST_IP'] = '10.0.3.1'
         if 'LXC_GUEST_IP' not in os.environ.keys():
             os.environ['LXC_GUEST_IP'] = '10.0.3.5'
 
     # Disable for MacOS if no SDK found
     if args.macos and not os.path.isfile(
-            'gitian-builder/inputs/MacOSX10.14.sdk.tar.gz'):
+            'gitian-builder/inputs/Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz'):
         print('Cannot build for MacOS, SDK does not exist. Will build for other OSes')
         args.macos = False
 
     script_name = os.path.basename(sys.argv[0])
     # Signer and version shouldn't be empty
     if args.signer == '':
         print(script_name + ': Missing signer.')
         print('Try ' + script_name + ' --help for more information')
         exit(1)
     if args.version == '':
         print(script_name + ': Missing version.')
         print('Try ' + script_name + ' --help for more information')
         exit(1)
 
     # Add leading 'v' for tags
     if args.commit and args.pull:
         raise Exception('Cannot have both commit and pull')
     args.commit = ('' if args.commit else 'v') + args.version
 
     if args.setup:
         setup()
 
     os.chdir('bitcoin-abc')
     if args.pull:
         subprocess.check_call(
             ['git', 'fetch', args.url, 'refs/pull/' + args.version + '/merge'])
         os.chdir('../gitian-builder/inputs/bitcoin')
         subprocess.check_call(
             ['git', 'fetch', args.url, 'refs/pull/' + args.version + '/merge'])
         args.commit = subprocess.check_output(
             ['git', 'show', '-s', '--format=%H', 'FETCH_HEAD'], universal_newlines=True, encoding='utf8').strip()
         args.version = 'pull-' + args.version
     print(args.commit)
     subprocess.check_call(['git', 'fetch'])
     subprocess.check_call(['git', 'checkout', args.commit])
     os.chdir(workdir)
 
     if args.build:
         build()
 
     if args.sign:
         sign()
 
     if args.verify:
         verify()
 
 
 if __name__ == '__main__':
     main()
diff --git a/contrib/gitian-descriptors/gitian-osx.yml b/contrib/gitian-descriptors/gitian-osx.yml
index 44f5f4d35..338f7894a 100644
--- a/contrib/gitian-descriptors/gitian-osx.yml
+++ b/contrib/gitian-descriptors/gitian-osx.yml
@@ -1,200 +1,200 @@
 ---
 name: "bitcoin-abc-osx"
 enable_cache: true
 distro: "debian"
 suites:
 - "buster"
 architectures:
 - "amd64"
 packages:
 - "autoconf"
 - "automake"
 - "bsdmainutils"
 - "ca-certificates"
 - "curl"
 - "faketime"
 - "fonts-tuffy"
 - "g++"
 - "git"
 - "imagemagick"
 - "libbz2-dev"
 - "libcap-dev"
 - "librsvg2-bin"
 - "libtiff-tools"
 - "libtinfo5"
 - "libtool"
 - "libz-dev"
 - "ninja-build"
 - "pkg-config"
 - "python3"
 - "python3-dev"
 - "python3-setuptools"
 # FIXME: these dependencies are only required to make CMake happy when building
 # native tools. They can be removed when the `NativeExecutable.cmake` gets
 # improved to avoid requiring all the bitcoin-abc dependencies.
 - "libboost-all-dev"
 - "libevent-dev"
 - "libssl-dev"
 repositories:
 - "distribution": "buster-backports"
   "source": "deb http://deb.debian.org/debian/ buster-backports main"
   packages:
   - "cmake"
 remotes:
 - "url": "https://github.com/Bitcoin-ABC/bitcoin-abc.git"
   "dir": "bitcoin"
 files:
-- "MacOSX10.14.sdk.tar.gz"
+- "Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz"
 script: |
   WRAP_DIR=$HOME/wrapped
   HOSTS="x86_64-apple-darwin16"
 
   # CMake toolchain file name differ from host name
   declare -A CMAKE_TOOLCHAIN_FILE
   CMAKE_TOOLCHAIN_FILE[x86_64-apple-darwin16]=OSX.cmake
 
   FAKETIME_HOST_PROGS=""
   FAKETIME_PROGS="ar ranlib date dmg genisoimage"
 
   export QT_RCC_TEST=1
   export QT_RCC_SOURCE_DATE_OVERRIDE=1
   export GZIP="-9n"
   export TAR_OPTIONS="--mtime="$REFERENCE_DATE\\\ $REFERENCE_TIME""
   export TZ="UTC"
   export BUILD_DIR=`pwd`
   mkdir -p ${WRAP_DIR}
   if test -n "$GBUILD_CACHE_ENABLED"; then
     export SOURCES_PATH=${GBUILD_COMMON_CACHE}
     export BASE_CACHE=${GBUILD_PACKAGE_CACHE}
     mkdir -p ${BASE_CACHE} ${SOURCES_PATH}
   fi
 
   export ZERO_AR_DATE=1
 
   function create_global_faketime_wrappers {
   for prog in ${FAKETIME_PROGS}; do
     echo '#!/usr/bin/env bash' > ${WRAP_DIR}/${prog}
     echo "REAL=\`which -a ${prog} | grep -v ${WRAP_DIR}/${prog} | head -1\`" >> ${WRAP_DIR}/${prog}
     echo 'export LD_PRELOAD=/usr/lib/x86_64-linux-gnu/faketime/libfaketime.so.1' >> ${WRAP_DIR}/${prog}
     echo "export FAKETIME=\"$1\"" >> ${WRAP_DIR}/${prog}
     echo "\$REAL \$@" >> $WRAP_DIR/${prog}
     chmod +x ${WRAP_DIR}/${prog}
   done
   }
 
   function create_per-host_faketime_wrappers {
   for i in $HOSTS; do
     for prog in ${FAKETIME_HOST_PROGS}; do
         echo '#!/usr/bin/env bash' > ${WRAP_DIR}/${i}-${prog}
         echo "REAL=\`which -a ${i}-${prog} | grep -v ${WRAP_DIR}/${i}-${prog} | head -1\`" >> ${WRAP_DIR}/${i}-${prog}
         echo 'export LD_PRELOAD=/usr/lib/x86_64-linux-gnu/faketime/libfaketime.so.1' >> ${WRAP_DIR}/${i}-${prog}
         echo "export FAKETIME=\"$1\"" >> ${WRAP_DIR}/${i}-${prog}
         echo "\$REAL \$@" >> $WRAP_DIR/${i}-${prog}
         chmod +x ${WRAP_DIR}/${i}-${prog}
     done
   done
   }
 
   # Faketime for depends so intermediate results are comparable
   export PATH_orig=${PATH}
   create_global_faketime_wrappers "2000-01-01 12:00:00"
   create_per-host_faketime_wrappers "2000-01-01 12:00:00"
   export PATH=${WRAP_DIR}:${PATH}
 
   cd bitcoin
   SOURCEDIR=`pwd`
   BASEPREFIX=`pwd`/depends
 
   mkdir -p ${BASEPREFIX}/SDKs
-  tar -C ${BASEPREFIX}/SDKs -xf ${BUILD_DIR}/MacOSX10.14.sdk.tar.gz
+  tar -C ${BASEPREFIX}/SDKs -xf ${BUILD_DIR}/Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz
 
   # Build dependencies for each host
   for i in $HOSTS; do
     make ${MAKEOPTS} -C ${BASEPREFIX} HOST="${i}"
   done
 
   # Faketime for binaries
   export PATH=${PATH_orig}
   create_global_faketime_wrappers "${REFERENCE_DATETIME}"
   create_per-host_faketime_wrappers "${REFERENCE_DATETIME}"
   export PATH=${WRAP_DIR}:${PATH}
 
   mkdir -p source_package
   pushd source_package
   cmake -GNinja .. \
     -DBUILD_BITCOIN_WALLET=OFF \
     -DBUILD_BITCOIN_ZMQ=OFF \
     -DBUILD_BITCOIN_ZMQ=OFF \
     -DBUILD_BITCOIN_SEEDER=OFF \
     -DBUILD_BITCOIN_CLI=OFF \
     -DBUILD_BITCOIN_TX=OFF \
     -DBUILD_BITCOIN_QT=OFF \
     -DBUILD_LIBBITCOINCONSENSUS=OFF \
     -DENABLE_CLANG_TIDY=OFF \
     -DENABLE_QRCODE=OFF \
     -DENABLE_UPNP=OFF \
     -DUSE_JEMALLOC=OFF
 
   ninja package_source
   SOURCEDIST=`echo bitcoin-abc-*.tar.gz`
   mv ${SOURCEDIST} ..
   popd
   DISTNAME=`echo ${SOURCEDIST} | sed 's/.tar.*//'`
 
   # Correct tar file order
   mkdir -p temp
   pushd temp
   tar xf ../$SOURCEDIST
   find bitcoin-abc-* | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
   popd
 
   ORIGPATH="$PATH"
   # Extract the release tarball into a dir for each host and build
   for i in ${HOSTS}; do
     export PATH=${BASEPREFIX}/${i}/native/bin:${ORIGPATH}
     mkdir -p distsrc-${i}
     cd distsrc-${i}
     INSTALLPATH=`pwd`/installed/${DISTNAME}
     mkdir -p ${INSTALLPATH}
     tar --strip-components=1 -xf ../$SOURCEDIST
 
     cmake -GNinja .. \
       -DCMAKE_TOOLCHAIN_FILE=${SOURCEDIR}/cmake/platforms/${CMAKE_TOOLCHAIN_FILE[${i}]} \
       -DCLIENT_VERSION_IS_RELEASE=ON \
       -DENABLE_CLANG_TIDY=OFF \
       -DENABLE_REDUCE_EXPORTS=ON \
       -DCMAKE_INSTALL_PREFIX=${INSTALLPATH} \
       -DCCACHE=OFF \
       -DGENISOIMAGE_EXECUTABLE="${WRAP_DIR}/genisoimage"
 
     ninja
 
     ninja install/strip
 
     export PYTHONPATH="${BASEPREFIX}/${i}/native/lib/python3/dist-packages:${PYTHONPATH}"
     ninja osx-deploydir
 
     OSX_VOLNAME="$(cat osx_volname)"
     mkdir -p unsigned-app-${i}
     cp osx_volname unsigned-app-${i}/
     cp contrib/macdeploy/detached-sig-apply.sh unsigned-app-${i}
     cp contrib/macdeploy/detached-sig-create.sh unsigned-app-${i}
     cp ${BASEPREFIX}/${i}/native/bin/dmg ${BASEPREFIX}/${i}/native/bin/genisoimage unsigned-app-${i}
     cp ${BASEPREFIX}/${i}/native/bin/${i}-codesign_allocate unsigned-app-${i}/codesign_allocate
     cp ${BASEPREFIX}/${i}/native/bin/${i}-pagestuff unsigned-app-${i}/pagestuff
     mv dist unsigned-app-${i}
     pushd unsigned-app-${i}
     find . | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-osx-unsigned.tar.gz
     popd
 
     ninja osx-dmg
     ${WRAP_DIR}/dmg dmg "${OSX_VOLNAME}.dmg" ${OUTDIR}/${DISTNAME}-osx-unsigned.dmg
 
     cd installed
     find -path "*.app*" -type f -executable -exec mv {} ${DISTNAME}/bin/bitcoin-qt \;
     find ${DISTNAME} -not -path "*.app*" | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}.tar.gz
     cd ../../
   done
   mkdir -p $OUTDIR/src
   mv $SOURCEDIST $OUTDIR/src
   mv ${OUTDIR}/${DISTNAME}-x86_64-*.tar.gz ${OUTDIR}/${DISTNAME}-osx64.tar.gz
diff --git a/contrib/macdeploy/README.md b/contrib/macdeploy/README.md
index 505e86e17..ea143c17d 100644
--- a/contrib/macdeploy/README.md
+++ b/contrib/macdeploy/README.md
@@ -1,135 +1,127 @@
 # MacOS Deployment
 
 The `macdeployqtplus` script should not be run manually. Instead, after building as usual:
 
 ```bash
 ninja osx-dmg
 ```
 
 During the deployment process, the disk image window will pop up briefly
 when the fancy settings are applied. This is normal, please do not interfere,
 the process will unmount the DMG and cleanup before finishing.
 
 When complete, it will have produced `Bitcoin-ABC.dmg`.
 
 ## SDK Extraction
 
-`Xcode.app` is packaged in a `.xip` archive.
-This makes the SDK less-trivial to extract on non-macOS machines.
-One approach (tested on Debian Buster) is outlined below:
+### Step 1: Obtaining `Xcode.app`
 
-```bash
-
-apt install clang cpio git liblzma-dev libxml2-dev libssl-dev make
-
-git clone https://github.com/tpoechtrager/xar
-pushd xar/xar
-./configure
-make
-make install
-popd
+Our current macOS SDK
+(`Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz`) can be
+extracted from
+[Xcode_11.3.1.xip](https://download.developer.apple.com/Developer_Tools/Xcode_11.3.1/Xcode_11.3.1.xip).
+An Apple ID is needed to download this.
 
-git clone https://github.com/NiklasRosenstein/pbzx
-pushd pbzx
-clang -llzma -lxar pbzx.c -o pbzx -Wl,-rpath=/usr/local/lib
-popd
+After Xcode version 7.x, Apple started shipping the `Xcode.app` in a `.xip`
+archive. This makes the SDK less-trivial to extract on non-macOS machines. One
+approach (tested on Debian Buster) is outlined below:
 
-xar -xf Xcode_10.2.1.xip -C .
-
-./pbzx/pbzx -n Content | cpio -i
+```bash
+# Install/clone tools needed for extracting Xcode.app
+apt install cpio
 
-find Xcode.app -type d -name MacOSX.sdk -execdir sh -c 'tar -c MacOSX.sdk/ | gzip -9n > /MacOSX10.14.sdk.tar.gz' \;
+# Unpack Xcode_11.3.1.xip and place the resulting Xcode.app in your current
+# working directory
+python3 contrib/apple-sdk-tools/extract_xcode.py -f Xcode_11.3.1.xip | cpio -d -i
 ```
 
-on macOS the process is more straightforward:
+On macOS the process is more straightforward:
 
 ```bash
-xip -x Xcode_10.2.1.xip
-tar -C Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/ -czf MacOSX10.14.sdk.tar.gz MacOSX.sdk
+xip -x Xcode_11.3.1.xip
 ```
 
-Our previously used macOS SDK (`MacOSX10.11.sdk`) can be extracted from
-[Xcode 7.3.1 dmg](https://developer.apple.com/devcenter/download.action?path=/Developer_Tools/Xcode_7.3.1/Xcode_7.3.1.dmg).
-The script [`extract-osx-sdk.sh`](./extract-osx-sdk.sh) automates this. First
-ensure the DMG file is in the current directory, and then run the script. You
-may wish to delete the `intermediate 5.hfs` file and `MacOSX10.11.sdk` (the
-directory) when you've confirmed the extraction succeeded.
+### Step 2: Generating `Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz` from `Xcode.app`
+
+To generate `Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz`, run
+the script [`gen-sdk`](./gen-sdk) with the path to `Xcode.app` (extracted in the
+previous stage) as the first argument.
 
 ```bash
-apt-get install p7zip-full sleuthkit
-contrib/macdeploy/extract-osx-sdk.sh
-rm -rf 5.hfs MacOSX10.11.sdk
+# Generate a Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz from
+# the supplied Xcode.app
+./contrib/macdeploy/gen-sdk '/path/to/Xcode.app'
 ```
 
 ## Deterministic macOS DMG Notes
 Working macOS DMGs are created in Linux by combining a recent `clang`, the Apple
 `binutils` (`ld`, `ar`, etc) and DMG authoring tools.
 
 Apple uses `clang` extensively for development and has upstreamed the necessary
 functionality so that a vanilla clang can take advantage. It supports the use of `-F`,
 `-target`, `-mmacosx-version-min`, and `--sysroot`, which are all necessary when
 building for macOS.
 
 Apple's version of `binutils` (called `cctools`) contains lots of functionality missing in the
 FSF's `binutils`. In addition to extra linker options for frameworks and sysroots, several
 other tools are needed as well such as `install_name_tool`, `lipo`, and `nmedit`. These
 do not build under Linux, so they have been patched to do so. The work here was used as
 a starting point: [mingwandroid/toolchain4](https://github.com/mingwandroid/toolchain4).
 
 In order to build a working toolchain, the following source packages are needed from
 Apple: `cctools`, `dyld`, and `ld64`.
 
 These tools inject timestamps by default, which produce non-deterministic binaries. The
 `ZERO_AR_DATE` environment variable is used to disable that.
 
 This version of `cctools` has been patched to use the current version of `clang`'s headers
 and its `libLTO.so` rather than those from `llvmgcc`, as it was originally done in `toolchain4`.
 
 To complicate things further, all builds must target an Apple SDK. These SDKs are free to
 download, but not redistributable. To obtain it, register for an Apple Developer Account,
-then download [Xcode 10.2.1](https://download.developer.apple.com/Developer_Tools/Xcode_10.2.1/Xcode_10.2.1.xip).
+then download [Xcode_11.3.1](https://download.developer.apple.com/Developer_Tools/Xcode_11.3.1/Xcode_11.3.1.xip).
 
 This file is many gigabytes in size, but most (but not all) of what we need is
 contained only in a single directory:
 
 ```bash
-Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.14.sdk
+Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk
 ```
 
 See the SDK Extraction notes above for how to obtain it.
 
 The Gitian descriptors build 2 sets of files: Linux tools, then Apple binaries which are
 created using these tools. The build process has been designed to avoid including the
 SDK's files in Gitian's outputs. All interim tarballs are fully deterministic and may be freely
 redistributed.
 
 `genisoimage` is used to create the initial DMG. It is not deterministic as-is, so it has been
 patched. A system `genisoimage` will work fine, but it will not be deterministic because
 the file-order will change between invocations. The patch can be seen here: [cdrkit-deterministic.patch](https://github.com/bitcoin/bitcoin/blob/master/depends/patches/native_cdrkit/cdrkit-deterministic.patch).
 No effort was made to fix this cleanly, so it likely leaks memory badly, however it's only used for
 a single invocation, so that's no real concern.
 
 `genisoimage` cannot compress DMGs, so afterwards, the DMG tool from the
 `libdmg-hfsplus` project is used to compress it. There are several bugs in this tool and its
 maintainer has seemingly abandoned the project.
 
 The DMG tool has the ability to create DMGs from scratch as well, but this functionality is
 broken. Only the compression feature is currently used. Ideally, the creation could be fixed
 and `genisoimage` would no longer be necessary.
 
 Background images and other features can be added to DMG files by inserting a
 `.DS_Store` before creation. This is generated by the script `contrib/macdeploy/custom_dsstore.py`.
 
 As of OS X 10.9 Mavericks, using an Apple-blessed key to sign binaries is a requirement in
 order to satisfy the new Gatekeeper requirements. Because this private key cannot be
 shared, we'll have to be a bit creative in order for the build process to remain somewhat
 deterministic. Here's how it works:
 
 - Builders use Gitian to create an unsigned release. This outputs an unsigned DMG which
   users may choose to bless and run. It also outputs an unsigned app structure in the form
   of a tarball, which also contains all of the tools that have been previously (deterministically)
   built in order to create a final DMG.
 - The Apple keyholder uses this unsigned app to create a detached signature, using the
   script that is also included there. Detached signatures are available from this [repository](https://github.com/bitcoin-core/bitcoin-detached-sigs).
 - Builders feed the unsigned app + detached signature back into Gitian. It uses the
   pre-built tools to recombine the pieces into a deterministic DMG.
diff --git a/contrib/macdeploy/gen-sdk b/contrib/macdeploy/gen-sdk
new file mode 100755
index 000000000..457d8f5e6
--- /dev/null
+++ b/contrib/macdeploy/gen-sdk
@@ -0,0 +1,94 @@
+#!/usr/bin/env python3
+import argparse
+import plistlib
+import pathlib
+import sys
+import tarfile
+import gzip
+import os
+import contextlib
+
+@contextlib.contextmanager
+def cd(path):
+    """Context manager that restores PWD even if an exception was raised."""
+    old_pwd = os.getcwd()
+    os.chdir(str(path))
+    try:
+        yield
+    finally:
+        os.chdir(old_pwd)
+
+def run():
+    parser = argparse.ArgumentParser(
+        description=__doc__, formatter_class=argparse.RawTextHelpFormatter)
+
+    parser.add_argument('xcode_app', metavar='XCODEAPP', nargs=1)
+    parser.add_argument("-o", metavar='OUTSDKTGZ', nargs=1, dest='out_sdktgz', required=False)
+
+    args = parser.parse_args()
+
+    xcode_app = pathlib.Path(args.xcode_app[0]).resolve()
+    assert xcode_app.is_dir(), "The supplied Xcode.app path '{}' either does not exist or is not a directory".format(xcode_app)
+
+    xcode_app_plist = xcode_app.joinpath("Contents/version.plist")
+    with xcode_app_plist.open('rb') as fp:
+        pl = plistlib.load(fp)
+        xcode_version = pl['CFBundleShortVersionString']
+        xcode_build_id = pl['ProductBuildVersion']
+    print("Found Xcode (version: {xcode_version}, build id: {xcode_build_id})".format(xcode_version=xcode_version, xcode_build_id=xcode_build_id))
+
+    sdk_dir = xcode_app.joinpath("Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk")
+    sdk_plist = sdk_dir.joinpath("System/Library/CoreServices/SystemVersion.plist")
+    with sdk_plist.open('rb') as fp:
+        pl = plistlib.load(fp)
+        sdk_version = pl['ProductVersion']
+        sdk_build_id = pl['ProductBuildVersion']
+    print("Found MacOSX SDK (version: {sdk_version}, build id: {sdk_build_id})".format(sdk_version=sdk_version, sdk_build_id=sdk_build_id))
+
+    out_name = "Xcode-{xcode_version}-{xcode_build_id}-extracted-SDK-with-libcxx-headers".format(xcode_version=xcode_version, xcode_build_id=xcode_build_id)
+
+    xcode_libcxx_dir = xcode_app.joinpath("Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1")
+    assert xcode_libcxx_dir.is_dir()
+
+    if args.out_sdktgz:
+        out_sdktgz_path = pathlib.Path(args.out_sdktgz_path)
+    else:
+        # Construct our own out_sdktgz if not specified on the command line
+        out_sdktgz_path = pathlib.Path("./{}.tar.gz".format(out_name))
+
+    def tarfp_add_with_base_change(tarfp, dir_to_add, alt_base_dir):
+        """Add all files in dir_to_add to tarfp, but prepent MEMBERPREFIX to the files'
+        names
+
+        e.g. if the only file under /root/bazdir is /root/bazdir/qux, invoking:
+
+            tarfp_add_with_base_change(tarfp, "foo/bar", "/root/bazdir")
+
+        would result in the following members being added to tarfp:
+
+            foo/bar/             -> corresponding to /root/bazdir
+            foo/bar/qux          -> corresponding to /root/bazdir/qux
+
+        """
+        def change_tarinfo_base(tarinfo):
+            if tarinfo.name and tarinfo.name.startswith("./"):
+                tarinfo.name = str(pathlib.Path(alt_base_dir, tarinfo.name))
+            if tarinfo.linkname and tarinfo.linkname.startswith("./"):
+                tarinfo.linkname = str(pathlib.Path(alt_base_dir, tarinfo.linkname))
+            return tarinfo
+        with cd(dir_to_add):
+            tarfp.add(".", recursive=True, filter=change_tarinfo_base)
+
+    print("Creating output .tar.gz file...")
+    with out_sdktgz_path.open("wb") as fp:
+        with gzip.GzipFile(fileobj=fp, compresslevel=9, mtime=0) as gzf:
+            with tarfile.open(mode="w", fileobj=gzf) as tarfp:
+                print("Adding MacOSX SDK {} files...".format(sdk_version))
+                tarfp_add_with_base_change(tarfp, sdk_dir, out_name)
+                print("Adding libc++ headers...")
+                tarfp_add_with_base_change(tarfp, xcode_libcxx_dir, "{}/usr/include/c++/v1".format(out_name))
+    print("Done! Find the resulting gzipped tarball at:")
+    print(out_sdktgz_path.resolve())
+
+if __name__ == '__main__':
+    run()
diff --git a/contrib/teamcity/gitian.sh b/contrib/teamcity/gitian.sh
index 517c92dbc..8a578f9a1 100755
--- a/contrib/teamcity/gitian.sh
+++ b/contrib/teamcity/gitian.sh
@@ -1,50 +1,50 @@
 #!/usr/bin/env bash
 
 export LC_ALL=C
 
 set -euxo pipefail
 
 : "${TOPLEVEL:=$(git rev-parse --show-toplevel)}"
 : "${BUILD_DIR:=${TOPLEVEL}/build}"
 : "${THREADS:=$(nproc || sysctl -n hw.ncpu)}"
 
 COMMIT=$(git -C "${TOPLEVEL}" rev-parse HEAD)
 export COMMIT
 export USE_DOCKER=1
 
 cd "${TOPLEVEL}/contrib/gitian-builder"
 
 ./bin/make-base-vm --docker --arch amd64 --distro debian --suite buster
 
 if [[ "${OS_NAME}" == "osx" ]]; then
-  OSX_SDK="MacOSX10.14.sdk.tar.gz"
-  OSX_SDK_SHA256="2322086a96349db832abbcadea493b79db843553a2e604163238d99fa058a286"
+  OSX_SDK="Xcode-11.3.1-11C505-extracted-SDK-with-libcxx-headers.tar.gz"
+  OSX_SDK_SHA256="a1b8af4c4d82d519dd5aff2135fe56184fa758c30e310b5fb4bfc8d9d3b45d8a"
   OSX_SDK_DIR=~/.abc-build-cache/osx-sdk
   mkdir -p "${OSX_SDK_DIR}"
   pushd "${OSX_SDK_DIR}"
   if ! echo "${OSX_SDK_SHA256}  ${OSX_SDK}" | sha256sum -c; then
     rm -f "${OSX_SDK}"
     wget https://storage.googleapis.com/27cd7b2a42a430926cc621acdc3bda72a8ed2b0efc080e3/"${OSX_SDK}"
     echo "${OSX_SDK_SHA256}  ${OSX_SDK}" | sha256sum -c
   fi
   popd
 
   mkdir -p inputs
   cp "${OSX_SDK_DIR}/${OSX_SDK}" inputs/"${OSX_SDK}"
 fi
 
 RESULT_DIR="${BUILD_DIR}/gitian-results"
 OS_DIR="${RESULT_DIR}/${OS_NAME}"
 mkdir -p "${OS_DIR}"
 
 move_log() {
   mv var/install.log "${RESULT_DIR}/"
   mv var/build.log "${RESULT_DIR}/"
 }
 trap "move_log" ERR
 
 ./bin/gbuild -j${THREADS} -m3500 --commit bitcoin=${COMMIT} --url bitcoin="${TOPLEVEL}" "${TOPLEVEL}/contrib/gitian-descriptors/gitian-${OS_NAME}.yml"
 
 move_log
 mv result/*.yml "${OS_DIR}/"
 mv build/out/* "${OS_DIR}/"
diff --git a/depends/hosts/darwin.mk b/depends/hosts/darwin.mk
index 1bc4fb818..114732952 100644
--- a/depends/hosts/darwin.mk
+++ b/depends/hosts/darwin.mk
@@ -1,16 +1,20 @@
 OSX_MIN_VERSION=10.12
-OSX_SDK_VERSION=10.14
-OSX_SDK=$(SDK_PATH)/MacOSX$(OSX_SDK_VERSION).sdk
-darwin_CC=clang -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK)
-darwin_CXX=clang++ -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -stdlib=libc++
+OSX_SDK_VERSION=10.15.1
+XCODE_VERSION=11.3.1
+XCODE_BUILD_ID=11C505
+LD64_VERSION=530
+
+OSX_SDK=$(SDK_PATH)/Xcode-$(XCODE_VERSION)-$(XCODE_BUILD_ID)-extracted-SDK-with-libcxx-headers
+darwin_CC=clang -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -mlinker-version=$(LD64_VERSION)
+darwin_CXX=clang++ -target $(host) -mmacosx-version-min=$(OSX_MIN_VERSION) --sysroot $(OSX_SDK) -stdlib=libc++ -mlinker-version=$(LD64_VERSION)
 
 darwin_CFLAGS=-pipe
 darwin_CXXFLAGS=$(darwin_CFLAGS)
 
 darwin_release_CFLAGS=-O2
 darwin_release_CXXFLAGS=$(darwin_release_CFLAGS)
 
 darwin_debug_CFLAGS=-O1
 darwin_debug_CXXFLAGS=$(darwin_debug_CFLAGS)
 
 darwin_native_toolchain=native_cctools
diff --git a/depends/packages/native_cctools.mk b/depends/packages/native_cctools.mk
index edca40e4f..416c1f07c 100644
--- a/depends/packages/native_cctools.mk
+++ b/depends/packages/native_cctools.mk
@@ -1,78 +1,76 @@
 package=native_cctools
-$(package)_version=3764b223c011574971ee3ae09ce968ba5dc2f00f
+$(package)_version=4da2f3b485bcf4cef526f30c0b8c0bcda99cdbb4
 $(package)_download_path=https://github.com/tpoechtrager/cctools-port/archive
 $(package)_file_name=$($(package)_version).tar.gz
-$(package)_sha256_hash=3e35907bf376269a844df08e03cbb43e345c88125374f2228e03724b5f9a2a04
+$(package)_sha256_hash=a2d491c0981cef72fee2b833598f20f42a6c44a7614a61c439bda93d56446fec
 $(package)_build_subdir=cctools
-$(package)_clang_version=6.0.1
+$(package)_clang_version=8.0.0
 $(package)_clang_download_path=https://releases.llvm.org/$($(package)_clang_version)
 $(package)_clang_download_file=clang+llvm-$($(package)_clang_version)-x86_64-linux-gnu-ubuntu-16.04.tar.xz
 $(package)_clang_file_name=clang-llvm-$($(package)_clang_version)-x86_64-linux-gnu-ubuntu-16.04.tar.xz
-$(package)_clang_sha256_hash=7ea204ecd78c39154d72dfc0d4a79f7cce1b2264da2551bb2eef10e266d54d91
+$(package)_clang_sha256_hash=87b88d620284d1f0573923e6f7cc89edccf11d19ebaec1cfb83b4f09ac5db09c
 
 $(package)_libtapi_version=3efb201881e7a76a21e0554906cf306432539cef
 $(package)_libtapi_download_path=https://github.com/tpoechtrager/apple-libtapi/archive
 $(package)_libtapi_download_file=$($(package)_libtapi_version).tar.gz
 $(package)_libtapi_file_name=$($(package)_libtapi_version).tar.gz
 $(package)_libtapi_sha256_hash=380c1ca37cfa04a8699d0887a8d3ee1ad27f3d08baba78887c73b09485c0fbd3
 
 $(package)_extra_sources=$($(package)_clang_file_name)
 $(package)_extra_sources += $($(package)_libtapi_file_name)
 
 define $(package)_fetch_cmds
 $(call fetch_file,$(package),$($(package)_download_path),$($(package)_download_file),$($(package)_file_name),$($(package)_sha256_hash)) && \
 $(call fetch_file,$(package),$($(package)_clang_download_path),$($(package)_clang_download_file),$($(package)_clang_file_name),$($(package)_clang_sha256_hash)) && \
 $(call fetch_file,$(package),$($(package)_libtapi_download_path),$($(package)_libtapi_download_file),$($(package)_libtapi_file_name),$($(package)_libtapi_sha256_hash))
 endef
 
 define $(package)_extract_cmds
   mkdir -p $($(package)_extract_dir) && \
   echo "$($(package)_sha256_hash)  $($(package)_source)" > $($(package)_extract_dir)/.$($(package)_file_name).hash && \
   echo "$($(package)_clang_sha256_hash)  $($(package)_source_dir)/$($(package)_clang_file_name)" >> $($(package)_extract_dir)/.$($(package)_file_name).hash && \
   echo "$($(package)_libtapi_sha256_hash)  $($(package)_source_dir)/$($(package)_libtapi_file_name)" >> $($(package)_extract_dir)/.$($(package)_file_name).hash && \
   $(build_SHA256SUM) -c $($(package)_extract_dir)/.$($(package)_file_name).hash && \
   mkdir -p toolchain/bin toolchain/lib/clang/$($(package)_clang_version)/include && \
   mkdir -p libtapi && \
   tar --no-same-owner --strip-components=1 -C libtapi -xf $($(package)_source_dir)/$($(package)_libtapi_file_name) && \
   tar --no-same-owner --strip-components=1 -C toolchain -xf $($(package)_source_dir)/$($(package)_clang_file_name) && \
   rm -f toolchain/lib/libc++abi.so* && \
   tar --no-same-owner --strip-components=1 -xf $($(package)_source)
 endef
 
 define $(package)_set_vars
   $(package)_config_opts=--target=$(host) --disable-lto-support --with-libtapi=$($(package)_extract_dir)
   $(package)_ldflags+=-Wl,-rpath=\\$$$$$$$$\$$$$$$$$ORIGIN/../lib
   $(package)_cc=$($(package)_extract_dir)/toolchain/bin/clang
   $(package)_cxx=$($(package)_extract_dir)/toolchain/bin/clang++
 endef
 
 define $(package)_preprocess_cmds
   CC=$($(package)_cc) CXX=$($(package)_cxx) INSTALLPREFIX=$($(package)_extract_dir) ./libtapi/build.sh && \
   CC=$($(package)_cc) CXX=$($(package)_cxx) INSTALLPREFIX=$($(package)_extract_dir) ./libtapi/install.sh && \
   sed -i.old "/define HAVE_PTHREADS/d" $($(package)_build_subdir)/ld64/src/ld/InputFiles.h
 endef
 
 define $(package)_config_cmds
   $($(package)_autoconf)
 endef
 
 define $(package)_build_cmds
   $(MAKE) -j$(JOBS)
 endef
 
 define $(package)_stage_cmds
   $(MAKE) DESTDIR=$($(package)_staging_dir) install && \
   mkdir -p $($(package)_staging_prefix_dir)/lib/ && \
   cd $($(package)_extract_dir) && \
   cp lib/libtapi.so.6 $($(package)_staging_prefix_dir)/lib/ && \
   cd $($(package)_extract_dir)/toolchain && \
   mkdir -p $($(package)_staging_prefix_dir)/lib/clang/$($(package)_clang_version)/include && \
   mkdir -p $($(package)_staging_prefix_dir)/bin $($(package)_staging_prefix_dir)/include && \
   cp bin/clang $($(package)_staging_prefix_dir)/bin/ &&\
   cp -P bin/clang++ $($(package)_staging_prefix_dir)/bin/ &&\
   cp lib/libLTO.so $($(package)_staging_prefix_dir)/lib/ && \
   cp -rf lib/clang/$($(package)_clang_version)/include/* $($(package)_staging_prefix_dir)/lib/clang/$($(package)_clang_version)/include/ && \
-  cp bin/llvm-dsymutil $($(package)_staging_prefix_dir)/bin/$(host)-dsymutil && \
-  if `test -d include/c++/`; then cp -rf include/c++/ $($(package)_staging_prefix_dir)/include/; fi && \
-  if `test -d lib/c++/`; then cp -rf lib/c++/ $($(package)_staging_prefix_dir)/lib/; fi
+  cp bin/dsymutil $($(package)_staging_prefix_dir)/bin/$(host)-dsymutil
 endef