Add build script

.gitignore

@@ -1,2 +1,4 @@
 vendor/
-.idea/
+.idea/
+build/
+certs/

build.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+if [ $# -eq 0 ]; then
+    echo You need to pass the version as first parameter.
+    exit 1
+fi
+
+VERSION=$1
+DATE=`date "+%F-%T"`
+COMMIT=`git rev-parse --verify HEAD`
+BRANCH=`git rev-parse --abbrev-ref HEAD`
+URL=github.com/gotify/server
+PREFIX=gotify-$VERSION
+DEST=./build
+TARGETS=linux/arm64,linux/amd64,linux/arm-7,windows-10/amd64
+LICENSES=./licenses/
+
+xgo -ldflags "-X main.Version=$VERSION -X main.BuildDate=$DATE -X main.Commit=$COMMIT -X main.Branch=$BRANCH" -targets $TARGETS -dest $DEST -out $PREFIX $URL
+
+mkdir $LICENSES
+for LICENSE in $(/bin/find vendor/ -name LICENSE | grep -v monkey); do
+    DIR=$(echo $LICENSE | tr "/" _ | sed -e 's/vendor_//; s/_LICENSE//')
+    mkdir $LICENSES$DIR
+    cp $LICENSE $LICENSES$DIR
+done
+
+for BIN in build/*; do
+   zip -j $BIN.zip $BIN LICENSE
+   zip -ur $BIN.zip $LICENSES
+done
+
+rm -rf $LICENSES