diff --git a/.appveyor.yml b/.appveyor.yml
new file mode 100644
index 0000000..865c125
--- /dev/null
+++ b/.appveyor.yml
@@ -0,0 +1,32 @@
+build:
+  verbosity: detailed
+
+branches:
+  only:
+    - master
+    - development
+
+platform: x64
+
+environment:
+  matrix:
+    - GENERATOR: Visual Studio 16 2019
+      BUILD_TYPE: Debug
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+
+build_script:
+  - mkdir tmp
+  - cd tmp
+  - curl -fsSL "https://github.com/microsoft/GSL/archive/v2.0.0.zip" -o gsl.zip
+  - 7z x gsl.zip
+  - Xcopy /E /I GSL-2.0.0\include\gsl ..\include\extern\gsl\
+  - curl -fsSL "https://github.com/Tencent/rapidjson/archive/v1.1.0.zip" -o rapidjson.zip
+  - 7z x rapidjson.zip
+  - Xcopy /E /I rapidjson-1.1.0\include\rapidjson ..\include\extern\rapidjson
+  - cd ..
+  - mkdir build
+  - cd build
+  - cmake .. -G "%GENERATOR%" -A x64 -Dbuild_abi=ON -Dextended_test=ON
+  - cmake --build . --config %BUILD_TYPE%
+  - path=%cd%\%BUILD_TYPE%;%PATH%
+  - ctest --output-on-failure --build-config %BUILD_TYPE%
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9a30389..a0bd504 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,9 +19,9 @@ option(gen_coverage "Generate gcov coverage information in support envs" OFF)
 option(use_asan "Link tests with address sanitizer" OFF)
 
 # Check which dependencies are installed.
-find_path(libgsl gsl/gsl)
 find_library(libyaml yaml)
-find_path(librj rapidjson/reader.h)
+find_path(libgsl gsl/gsl HINTS ${PROJECT_SOURCE_DIR}/include/extern)
+find_path(librj rapidjson/reader.h HINTS ${PROJECT_SOURCE_DIR}/include/extern)
 if (NOT librj)
   CHECK_INCLUDE_FILE_CXX("rapidjson/reader.h" librj)
 endif ()
diff --git a/README.md b/README.md
index 8884856..3e16100 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,7 @@ Dart
 ==============
 
 [![Build Status](https://travis-ci.com/target/libdart.svg?branch=master)](https://travis-ci.com/target/libdart)
+[![Build status](https://ci.appveyor.com/api/projects/status/trv6dpc03nm3d9df?svg=true)](https://ci.appveyor.com/project/Cfretz244/libdart)
 [![Coverage Status](https://coveralls.io/repos/github/target/libdart/badge.svg?branch=master)](https://coveralls.io/github/target/libdart?branch=master)
 ### A High Performance, Network Optimized, JSON Manipulation Library
 **Dart** is both a wire-level binary `JSON` protocol, along with a high performance,
diff --git a/include/dart/abi.h b/include/dart/abi.h
index 9db4a8d..2b6d639 100644
--- a/include/dart/abi.h
+++ b/include/dart/abi.h
@@ -8118,6 +8118,20 @@ extern "C" {
    */
   DART_ABI_EXPORT char const* dart_get_error();
 
+  /**
+   *  @brief
+   *  Free a buffer returned from one of the dart_*_dup_bytes functions
+   *
+   *  @details
+   *  Dart requires its buffer representations to be aligned to a 64-bit
+   *  boundary for internal design reasons (simplifies alignment logic significantly).
+   *  Very easy to do on *nix machines with posix_memalign, which allocates aligned
+   *  memory that can be passed directly to free.
+   *  Windows, on the other hand, has _aligned_malloc and _aligned_free, which MUST
+   *  be paired, so to write portable code this function must exist.
+   */
+  DART_ABI_EXPORT void dart_aligned_free(void* ptr);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/generic.cc b/src/generic.cc
index 393360b..704ea3a 100644
--- a/src/generic.cc
+++ b/src/generic.cc
@@ -1644,4 +1644,8 @@ extern "C" {
     return dart::detail::errmsg.data();
   }
 
+  void dart_aligned_free(void* ptr) {
+    dart::shim::aligned_free(ptr);
+  }
+
 }
diff --git a/test/buffer_abi_unit_tests.cc b/test/buffer_abi_unit_tests.cc
index 5381571..8e56d20 100644
--- a/test/buffer_abi_unit_tests.cc
+++ b/test/buffer_abi_unit_tests.cc
@@ -512,8 +512,8 @@ SCENARIO("finalized buffer objects have unique object representations") {
         auto* ownone = dart_buffer_dup_bytes(&finone, &lenone);
         auto* owntwo = dart_buffer_dup_bytes(&fintwo, nullptr);
         auto guard = make_scope_guard([&] {
-          free(owntwo);
-          free(ownone);
+          dart_aligned_free(owntwo);
+          dart_aligned_free(ownone);
         });
         REQUIRE(lenone == lentwo);
         REQUIRE(std::memcmp(ownone, owntwo, lenone) == 0);
diff --git a/test/generic_abi_unit_tests.cc b/test/generic_abi_unit_tests.cc
index a898c19..fb9b1ff 100644
--- a/test/generic_abi_unit_tests.cc
+++ b/test/generic_abi_unit_tests.cc
@@ -1120,8 +1120,8 @@ SCENARIO("finalized objects have unique object representations") {
         auto* ownone = dart_dup_bytes(&finone, &lenone);
         auto* owntwo = dart_dup_bytes(&fintwo, &lentwo);
         auto guard = make_scope_guard([&] {
-          free(owntwo);
-          free(ownone);
+          dart_aligned_free(owntwo);
+          dart_aligned_free(ownone);
         });
         REQUIRE(lenone == lentwo);
         REQUIRE(std::memcmp(ownone, owntwo, lenone) == 0);
diff --git a/test/heap_abi_unit_tests.cc b/test/heap_abi_unit_tests.cc
index 740d38e..691d753 100644
--- a/test/heap_abi_unit_tests.cc
+++ b/test/heap_abi_unit_tests.cc
@@ -1118,8 +1118,8 @@ SCENARIO("heap finalized objects have unique object representations") {
         auto* ownone = dart_dup_bytes(&finone, &lenone);
         auto* owntwo = dart_dup_bytes(&fintwo, &lentwo);
         auto guard = make_scope_guard([&] {
-          free(owntwo);
-          free(ownone);
+          dart_aligned_free(owntwo);
+          dart_aligned_free(ownone);
         });
         REQUIRE(lenone == lentwo);
         REQUIRE(std::memcmp(ownone, owntwo, lenone) == 0);
diff --git a/test/json_test.cc b/test/json_test.cc
index 258e1e3..27ee179 100644
--- a/test/json_test.cc
+++ b/test/json_test.cc
@@ -255,22 +255,6 @@ TEST_CASE("dart_packet parses JSON via RapidJSON", "[json unit]") {
     compare_rj_dart_abi(packet, &bufferthree);
     compare_rj_dart_abi(packet, &bufferfour);
 
-    // Validate the underlying buffer.
-    auto pktdup = dart_take_bytes(dart_dup_bytes(&bufferone, nullptr));
-    auto pktduptwo = dart_take_bytes_rc(dart_dup_bytes(&bufferone, nullptr), DART_RC_SAFE);
-    auto bufferdup = dart_buffer_take_bytes(dart_buffer_dup_bytes(&bufferone, nullptr));
-    auto bufferduptwo = dart_buffer_take_bytes_rc(dart_buffer_dup_bytes(&bufferone, nullptr), DART_RC_SAFE);
-    auto guard_two = make_scope_guard([&] {
-      dart_destroy(&bufferduptwo);
-      dart_destroy(&bufferdup);
-      dart_destroy(&pktduptwo);
-      dart_destroy(&pktdup);
-    });
-    compare_rj_dart_abi(packet, &pktdup);
-    compare_rj_dart_abi(packet, &pktduptwo);
-    compare_rj_dart_abi(packet, &bufferdup);
-    compare_rj_dart_abi(packet, &bufferduptwo);
-
     // Generate JSON, reparse it, and validate it's still the same.
     rj::Document rjone, rjtwo, rjthree;
     auto* pktjson = dart_to_json(&pktone, nullptr);