diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index fe853d93..8c4c60a5 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -157,8 +157,7 @@ jobs:
       - name: Install compiler
         run: |
           sudo apt-get update && sudo apt-get install cmake -qyy
-          wget http://minetest.kitsunemimi.pw/mingw-w64-${{matrix.config.arch}}_11.2.0_ubuntu20.04.tar.xz -O mingw.tar.xz
-          sudo tar -xaf mingw.tar.xz -C /usr
+          ./scripts/ci-get-mingw.sh ${{matrix.config.arch}}
 
       - name: Build
         run: |
diff --git a/scripts/ci-build-mingw.sh b/scripts/ci-build-mingw.sh
index b3b898e2..736969f8 100755
--- a/scripts/ci-build-mingw.sh
+++ b/scripts/ci-build-mingw.sh
@@ -1,7 +1,7 @@
 #!/bin/bash -e
+topdir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
 [[ -z "$CC" || -z "$CXX" ]] && exit 255
-
 variant=win32
 [[ "$(basename "$CXX")" == "x86_64-"* ]] && variant=win64
 with_sdl=0
@@ -14,21 +14,24 @@ libpng_version=1.6.39
 sdl2_version=2.28.1
 zlib_version=1.2.13
 
+download () {
+	local url=$1
+	local filename=${url##*/}
+	local foldername=${filename%%[.-]*}
+
+	[ -d "./$foldername" ] && return 0
+    [ -e "$filename" ] || wget "$url" -O "$filename"
+	sha256sum -w -c <(grep -F "$filename" "$topdir/sha256sums.txt")
+	unzip -o "$filename" -d "$foldername"
+}
+
 mkdir -p libs
 pushd libs
 libs=$PWD
-[ -e libjpeg.zip ] || \
-	wget "http://minetest.kitsunemimi.pw/libjpeg-$libjpeg_version-$variant.zip" -O libjpeg.zip
-[ -e libpng.zip ] || \
-	wget "http://minetest.kitsunemimi.pw/libpng-$libpng_version-$variant.zip" -O libpng.zip
-[[ $with_sdl -eq 0 || -e sdl2.zip ]] || \
-	wget "http://minetest.kitsunemimi.pw/sdl2-$sdl2_version-$variant.zip" -O sdl2.zip
-[ -e zlib.zip ] || \
-	wget "http://minetest.kitsunemimi.pw/zlib-$zlib_version-$variant.zip" -O zlib.zip
-[ -d libjpeg ] || unzip -o libjpeg.zip -d libjpeg
-[ -d libpng ] || unzip -o libpng.zip -d libpng
-[[ $with_sdl -eq 0 || -d sdl2 ]] || unzip -o sdl2.zip -d sdl2
-[ -d zlib ] || unzip -o zlib.zip -d zlib
+download "http://minetest.kitsunemimi.pw/libjpeg-$libjpeg_version-$variant.zip"
+download "http://minetest.kitsunemimi.pw/libpng-$libpng_version-$variant.zip"
+[ $with_sdl -eq 1 ] && download "http://minetest.kitsunemimi.pw/sdl2-$sdl2_version-$variant.zip"
+download "http://minetest.kitsunemimi.pw/zlib-$zlib_version-$variant.zip"
 popd
 
 tmp=(
diff --git a/scripts/ci-get-mingw.sh b/scripts/ci-get-mingw.sh
new file mode 100755
index 00000000..c06670c3
--- /dev/null
+++ b/scripts/ci-get-mingw.sh
@@ -0,0 +1,12 @@
+#!/bin/bash
+set -e
+topdir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+[ -z "$1" ] && exit 255
+
+ver=11.2.0
+os=ubuntu20.04
+name="mingw-w64-${1}_${ver}_${os}.tar.xz"
+wget "http://minetest.kitsunemimi.pw/$name" -O "$name"
+sha256sum -w -c <(grep -F "$name" "$topdir/sha256sums.txt")
+sudo tar -xaf "$name" -C /usr
+rm -f "$name"
diff --git a/scripts/sha256sums.txt b/scripts/sha256sums.txt
new file mode 100644
index 00000000..4606d556
--- /dev/null
+++ b/scripts/sha256sums.txt
@@ -0,0 +1,10 @@
+934ef7f3897cebcbf39eed2fcb0be084c1ff1af4352ebc1f19cfb4a60020b1c7  libjpeg-2.1.5.1-win32.zip
+2b3054ddfd66c2b3f97ac65fb2b80be05649eeab98a822b952cbe388038d4aa1  libjpeg-2.1.5.1-win64.zip
+9d8d97c1af52d88d6fc44902375fb42225f0ee5cbf2199997d278579770f8850  libpng-1.6.39-win32.zip
+a4209e4de00f1674ba4cedf2ddf23881d429f6d2b5f9a4a26945c7cfbf12c384  libpng-1.6.39-win64.zip
+704817351dc54a5a4bb3b35db9316f4ff1b073b231b5f8dbbc3b4ff2f3e30fbe  mingw-w64-i686_11.2.0_ubuntu20.04.tar.xz
+d85ec9a7debe470ebeaa002af0a2843b83d40405d2a45fcc586c19f179362aab  mingw-w64-x86_64_11.2.0_ubuntu20.04.tar.xz
+192a14f42de64d65bbd3ba320330a51e8e05aa67afc4e300690cc9fc8b2d11b3  sdl2-2.28.1-win32.zip
+247d5ab923449fea042a8c47318a77e75ef3c056283049ad550935dae29fc26b  sdl2-2.28.1-win64.zip
+e9bab0a6fe07bcf6c5a8ff171dd63983e67f3aefd9b8f38e88bf20a3dc44678f  zlib-1.2.13-win32.zip
+9f3d4fd89958081917d2fdcaab1bbc947e3fb070d8b39a48d9cf11269dd52c24  zlib-1.2.13-win64.zip