diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 0000000..20591aa
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,45 @@
+---
+name: Tests
+on: [push, pull_request]
+
+jobs:
+  Test-Randombytes:
+    runs-on: "${{ matrix.os }}"
+    strategy:
+      matrix:
+        cc:
+          - gcc
+          - clang
+        os:
+          - ubuntu-latest
+          - macos-latest
+    env:
+      CC: "${{ matrix.cc }}"
+    steps:
+      - uses: actions/checkout@v3
+      - run: |
+          make check
+
+  Test-Randombytes-Musl:
+    runs-on: ubuntu-latest
+    env:
+      CC: musl-gcc
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install musl-tools
+        run: sudo apt-get install -y musl-tools
+      - run: make check
+
+  Test-Randombytes-Windows:
+    runs-on: windows-latest
+    strategy:
+      matrix:
+        arch:
+          - x64
+          - x86
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ilammy/msvc-dev-cmd@v1
+        with:
+          arch: ${{ matrix.arch }}
+      - run: cl /c /nologo /W3 /WX randombytes.c
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 74280d8..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,65 +0,0 @@
-language: c
-os:
-  - linux
-compiler:
-  - clang
-  - gcc
-arch:
-  - amd64
-  - arm64
-matrix:
-  include:
-    - os: linux
-      compiler: musl-gcc
-      arch: amd64
-      addons:
-        apt:
-          packages:
-            - musl
-            - musl-dev
-            - musl-tools
-    - os: linux
-      compiler: musl-gcc
-      arch: arm64
-      addons:
-        apt:
-          packages:
-            - musl
-            - musl-dev
-            - musl-tools
-    - language: node_js
-      node_js: "node"
-      sudo: required
-      services: ["docker"]
-      before_install:
-        - echo "$DOCKER_PASSWORD" | docker login -u "$DOCKER_USERNAME" --password-stdin
-        - docker run -dit --name emscripten -v $(pwd):/src trzeci/emscripten:sdk-incoming-64bit bash
-      script:
-        - docker exec -it emscripten make randombytes_test.js
-        - make check-js
-    - language: node_js
-      node_js: "lts/*"
-      sudo: required
-      services: ["docker"]
-      before_install:
-        - echo "$DOCKER_PASSWORD" | docker login -u "$DOCKER_USERNAME" --password-stdin
-        - docker run -dit --name emscripten -v $(pwd):/src trzeci/emscripten:sdk-incoming-64bit bash
-      script:
-        - docker exec -it emscripten make randombytes_test.js
-        - make check-js
-    - os: osx
-      language: c
-      osx_image: xcode10.1
-      compiler: gcc
-      addons:
-        homebrew:
-          packages:
-            - gcc@8
-    - os: osx
-      language: c
-      osx_image: xcode10.1
-      compiler: clang
-
-script:
-  - make
-  - make check
diff --git a/appveyor.yml b/appveyor.yml
deleted file mode 100644
index b4abaa9..0000000
--- a/appveyor.yml
+++ /dev/null
@@ -1,3 +0,0 @@
-image: Visual Studio 2015
-build_script:
-- cmd: clang -c randombytes.c
diff --git a/randombytes.c b/randombytes.c
index ff26b9a..aa771b1 100644
--- a/randombytes.c
+++ b/randombytes.c
@@ -76,17 +76,24 @@
 
 
 #if defined(_WIN32)
-static int randombytes_win32_randombytes(void* buf, const size_t n)
+static int randombytes_win32_randombytes(void* buf, size_t n)
 {
 	HCRYPTPROV ctx;
 	BOOL tmp;
+	DWORD to_read = 0;
+	const size_t MAX_DWORD = 0xFFFFFFFF;
 
 	tmp = CryptAcquireContext(&ctx, NULL, NULL, PROV_RSA_FULL,
 	                          CRYPT_VERIFYCONTEXT);
 	if (tmp == FALSE) return -1;
 
-	tmp = CryptGenRandom(ctx, n, (BYTE*) buf);
-	if (tmp == FALSE) return -1;
+	while (n > 0) {
+		to_read = (DWORD)(n < MAX_DWORD ? n : MAX_DWORD);
+		tmp = CryptGenRandom(ctx, to_read, (BYTE*) buf);
+		if (tmp == FALSE) return -1;
+		buf = ((char*)buf) + to_read;
+		n -= to_read;
+	}
 
 	tmp = CryptReleaseContext(ctx, 0);
 	if (tmp == FALSE) return -1;