diff --git a/.github/workflows/build-all.yaml b/.github/workflows/build-all.yaml
index a28a56aa9..af26d4716 100644
--- a/.github/workflows/build-all.yaml
+++ b/.github/workflows/build-all.yaml
@@ -19,7 +19,7 @@ jobs:
         --security-opt apparmor:unconfined
     strategy:
       matrix:
-        flavour: [pkg-appimage-snapshot, pkg-appimage-deployment, pkg-appimage]
+        flavour: [deployment, test, dev]
     steps:
       ## This is for debugging only and helps developing the workflow.
       # - name: Environment Variables
@@ -58,11 +58,14 @@ jobs:
           ldconfig
       - name: Build Oolite
         run: |
-          ShellScripts/common/build_oolite.sh ${{matrix.flavour}}
+          ./mk.sh build ${{matrix.flavour}} --github-repository="$GITHUB_REPOSITORY"
+      - name: Package Oolite
+        run: |
+          ./mk.sh pkg-appimage ${{matrix.flavour}}
       - name: Archive installer
         uses: actions/upload-artifact@v6
         with:
-          name: oolite-linux-${{matrix.flavour}}
+          name: oolite-linux-appimage-${{matrix.flavour}}
           path: |
             build/oolite*.AppImage
           retention-days: 5
@@ -90,11 +93,15 @@ jobs:
           fetch-depth: 0
       - name: Build flatpak
         run: |
-          installers/flatpak/create_flatpak.sh
+          echo "Installing gitversion..."
+          source ShellScripts/Linux/install_gitversion_fn.sh
+          mkdir -p /usr/local/bin
+          install_gitversion "."
+          ./mk.sh pkg-flatpak deployment --github-repository="$GITHUB_REPOSITORY"
       - name: Archive installer
         uses: actions/upload-artifact@v6
         with:
-          name: oolite-flatpak
+          name: oolite-linux-flatpak-deployment
           path: |
             build/space.oolite.Oolite*.flatpak
           retention-days: 5
@@ -103,7 +110,7 @@ jobs:
     runs-on: windows-latest
     strategy:
       matrix:
-        flavour: [pkg-win-snapshot, pkg-win-deployment, pkg-win]
+        flavour: [deployment, test, dev]
     steps:
       ## This is for debugging only and helps developing the workflow.
       # - name: Environment Variables
@@ -117,6 +124,7 @@ jobs:
       - name: Set up MSYS2
         uses: msys2/setup-msys2@v2
         with:
+          msystem: UCRT64
           update: true
           cache: false
       - name: Checkout Oolite
@@ -139,12 +147,20 @@ jobs:
         shell: msys2 {0}
         env:
           msystem: UCRT64
+          PYTHONUTF8: "1"
+        run: |
+          ./mk.sh build ${{matrix.flavour}} --github-repository="$GITHUB_REPOSITORY"
+      - name: Package Oolite
+        shell: msys2 {0}
+        env:
+          msystem: UCRT64
+          PYTHONUTF8: "1"
         run: |
-          ShellScripts/common/build_oolite.sh ${{matrix.flavour}}
+          ./mk.sh pkg-win ${{matrix.flavour}}
       - name: Archive installer
         uses: actions/upload-artifact@v6
         with:
-          name: oolite-windows-${{matrix.flavour}}
+          name: oolite-windows-nsis-${{matrix.flavour}}
           path: |
             build/OoliteInstall*.exe
           retention-days: 5
@@ -164,7 +180,7 @@ jobs:
         uses: actions/download-artifact@v7
         with:
           path: artifacts
-      - name: Calculate version number and set OOLITE_VERSION
+      - name: Calculate version number and set VER_FULL
         id: version
         run: |
           set -x          
@@ -184,14 +200,14 @@ jobs:
           echo "Found AppImage: $APPIMAGE_PATH"                    
           # 3. Run with packageinfo and extract the string inside quotes
           chmod +x "$APPIMAGE_PATH"
-          VERSION_STR=$("$APPIMAGE_PATH" packageinfo | awk -F'"' '/^[[:space:]]*version =/ {print $2; exit}')           
-          if [[ -z "$VERSION_STR" ]]; then
+          VER_FULL=$("$APPIMAGE_PATH" packageinfo | awk -F'"' '/^[[:space:]]*version =/ {print $2; exit}')           
+          if [[ -z "$VER_FULL" ]]; then
             echo "❌ Failed to extract version string from packageinfo output!" >&2
             exit 1
           fi                     
-          echo "Extracted Version: $VERSION_STR"          
+          echo "Extracted Version: $VER_FULL"          
           # 4. Output the extracted version for subsequent steps
-          echo "OOLITE_VERSION=$VERSION_STR" >> "$GITHUB_OUTPUT"
+          echo "VER_FULL=$VER_FULL" >> "$GITHUB_OUTPUT"
       - name: Remove old prereleases
         if: github.ref == 'refs/heads/master' || endsWith(github.ref, 'maintenance')
         uses: s00d/delete-older-releases@0.2.1
@@ -208,17 +224,17 @@ jobs:
         with:
           repo_token: "${{ secrets.GITHUB_TOKEN }}"
           # automatic_release_tag: "latest"
-          automatic_release_tag: "${{ steps.version.outputs.OOLITE_VERSION }}"
+          automatic_release_tag: "${{ steps.version.outputs.VER_FULL }}"
           prerelease: true
-          title: "Oolite ${{ steps.version.outputs.OOLITE_VERSION }}"
+          title: "Oolite ${{ steps.version.outputs.VER_FULL }}"
           files: |
-            artifacts/oolite-windows-pkg-win-snapshot/OoliteInstall-*-dev.exe
-            artifacts/oolite-windows-pkg-win-deployment/OoliteInstall-*.exe
-            artifacts/oolite-windows-pkg-win/OoliteInstall-*.exe
-            artifacts/oolite-linux-pkg-appimage-snapshot/*.AppImage
-            artifacts/oolite-linux-pkg-appimage-deployment/*.AppImage
-            artifacts/oolite-linux-pkg-appimage/*.AppImage
-            artifacts/oolite-flatpak/*.flatpak
+            artifacts/oolite-windows-nsis-deployment/OoliteInstall-*.exe
+            artifacts/oolite-windows-nsis-test/OoliteInstall-*.exe
+            artifacts/oolite-windows-nsis-dev/OoliteInstall-*-dev.exe
+            artifacts/oolite-linux-appimage-deployment/*.AppImage
+            artifacts/oolite-linux-appimage-test/*.AppImage
+            artifacts/oolite-linux-appimage-dev/*.AppImage
+            artifacts/oolite-linux-flatpak-deployment/*.flatpak
       - name: Remove old workflow runs
         if: github.ref == 'refs/heads/master' || endsWith(github.ref, 'maintenance')
         uses: Mattraks/delete-workflow-runs@v2
diff --git a/.github/workflows/test_builds.yaml b/.github/workflows/test_builds.yaml
index dfb1c4426..43bd7d77c 100644
--- a/.github/workflows/test_builds.yaml
+++ b/.github/workflows/test_builds.yaml
@@ -32,7 +32,7 @@ jobs:
           cat << EOF >> ~/.curlrc
           header = "Authorization: Bearer $GITHUB_TOKEN"
           header = "Accept: application/vnd.github+json"
-          EOF          
+          EOF
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
@@ -47,17 +47,16 @@ jobs:
       - name: Install Mozilla static library
         run: |
           ShellScripts/Linux/install_mozilla_js.sh system
-      - name: Build and test Oolite
-        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
+      - name: Build Oolite
         run: |
-          ShellScripts/common/build_oolite.sh test
-      - name: Build Oolite (no test)
-        if: github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
+          ./mk.sh build dev
+      - name: Test Oolite
+        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
         run: |
-          ShellScripts/common/build_oolite.sh
+          ./mk.sh test dev
       - name: Build AppImage
         run: |
-          ShellScripts/common/build_oolite.sh pkg-appimage-snapshot
+          ./mk.sh pkg-appimage dev
 
   fedora:
     runs-on: ubuntu-latest
@@ -82,7 +81,7 @@ jobs:
           cat << EOF >> ~/.curlrc
           header = "Authorization: Bearer $GITHUB_TOKEN"
           header = "Accept: application/vnd.github+json"
-          EOF          
+          EOF
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
@@ -97,17 +96,16 @@ jobs:
           ShellScripts/Linux/install_mozilla_js.sh system
           echo "/usr/local/lib64" | tee -a /etc/ld.so.conf
           ldconfig
-      - name: Build and test Oolite
-        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
+      - name: Build Oolite
         run: |
-          ShellScripts/common/build_oolite.sh test
-      - name: Build Oolite (no test)
-        if: github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
+          ./mk.sh build dev
+      - name: Test Oolite
+        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
         run: |
-          ShellScripts/common/build_oolite.sh
+          ./mk.sh test dev
       - name: Build AppImage
         run: |
-          ShellScripts/common/build_oolite.sh pkg-appimage-snapshot
+          ./mk.sh pkg-appimage dev
 
   arch:
     runs-on: ubuntu-latest
@@ -132,7 +130,7 @@ jobs:
           cat << EOF >> ~/.curlrc
           header = "Authorization: Bearer $GITHUB_TOKEN"
           header = "Accept: application/vnd.github+json"
-          EOF          
+          EOF
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
@@ -147,17 +145,16 @@ jobs:
           ShellScripts/Linux/install_mozilla_js.sh system
           echo "/usr/local/lib" | tee -a /etc/ld.so.conf
           ldconfig
-      - name: Build and test Oolite
-        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
+      - name: Build Oolite
         run: |
-          ShellScripts/common/build_oolite.sh test
-      - name: Build Oolite (no test)
-        if: github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
+          ./mk.sh build dev
+      - name: Test Oolite
+        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
         run: |
-          ShellScripts/common/build_oolite.sh
+          ./mk.sh test dev
       - name: Build AppImage
         run: |
-          ShellScripts/common/build_oolite.sh pkg-appimage-snapshot
+          ./mk.sh pkg-appimage dev
 
   windows:
     runs-on: windows-latest
@@ -191,18 +188,20 @@ jobs:
           EOF
           cp ~/.curlrc /c/Users/runneradmin/.curlrc 2>/dev/null || true          
           ShellScripts/Windows/install_deps.sh clang
-      - name: Build and test Oolite
-        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
+
+      - name: Build Oolite
         shell: msys2 {0}
         env:
           msystem: UCRT64
+          PYTHONUTF8: "1"
         run: |
-          ShellScripts/common/build_oolite.sh test
+          ./mk.sh build dev
 
-      - name: Build Oolite (no test)
-        if: github.event.pull_request.head.repo.full_name != github.event.pull_request.base.repo.full_name
+      - name: Test Oolite
+        if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
         shell: msys2 {0}
         env:
           msystem: UCRT64
+          PYTHONUTF8: "1"
         run: |
-          ShellScripts/common/build_oolite.sh
+          ./mk.sh test dev
diff --git a/Makefile b/Makefile
deleted file mode 100755
index 6a25ab871..000000000
--- a/Makefile
+++ /dev/null
@@ -1,97 +0,0 @@
-# Use bash as the explicit shell and enable strict error handling for safety
-SHELL := /bin/bash
-.SHELLFLAGS := -eu -o pipefail -c
-
-NATIVE_FILE ?= clang.ini
-BUILDER ?= unknown
-
-# Modern, self-documenting help target. 
-# It parses the '##' comments next to targets automatically.
-.PHONY: help
-help: ## Show this help message
-	@echo "Usage: make [target]"
-	@echo ""
-	@echo "Targets:"
-	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "  \033[36m%-25s\033[0m %s\n", $$1, $$2}'
-
-# Macro for Meson workflow
-define meson_build
-	meson setup build/meson_$(2) $(1) -Dgithub_repository=${GITHUB_REPOSITORY} --native-file $(NATIVE_FILE) --reconfigure 2>/dev/null || meson setup build/meson_$(2) $(1) -Dgithub_repository=${GITHUB_REPOSITORY} --native-file $(NATIVE_FILE)
-	meson compile -C build/meson_$(2)
-endef
-
-# Helper macro for syncing OXP files cleanly
-define sync_debug_oxp
-	mkdir -p build/meson_$(1)/oolite.app/AddOns
-	rm -rf build/meson_$(1)/oolite.app/AddOns/Basic-debug.oxp
-	cp -rf DebugOXP/Debug.oxp build/meson_$(1)/oolite.app/AddOns/Basic-debug.oxp
-endef
-
-##
-## Development Targets
-##
-
-.PHONY: release
-release: ## Build a test release executable
-	$(call meson_build,-Ddebug=false -Dstrip_bin=true -Db_lto=true,release)
-	$(call sync_debug_oxp,release)
-
-.PHONY: release-deployment
-release-deployment: ## Build a release deployment executable
-	$(call meson_build,-Ddeployment_release_configuration=true -Ddebug=false -Dstrip_bin=true -Db_lto=true,deployment)
-
-.PHONY: release-snapshot
-release-snapshot: ## Build a snapshot release executable
-	$(call meson_build,-Dsnapshot_build=true -Ddebug=false -Dstrip_bin=false,snapshot)
-	$(call sync_debug_oxp,snapshot)
-
-.PHONY: debug
-debug: ## Build a debug executable
-	$(call meson_build,-Ddebug=true -Dstrip_bin=false,debug)
-	$(call sync_debug_oxp,debug)
-
-.PHONY: test
-test: release-snapshot ## Run test suite
-	tests/run_test.sh
-
-.PHONY: clean
-clean: ## Remove all generated build artifacts
-	rm -rf build/meson_*
-
-.PHONY: all
-all: release release-deployment release-snapshot debug ## Build all standard development targets
-
-.PHONY: remake
-remake: clean all
-
-##
-## Packaging Targets
-##
-
-.PHONY: pkg-flatpak
-pkg-flatpak: ## Package a Flatpak application
-	./installers/flatpak/create_flatpak.sh
-
-.PHONY: pkg-appimage
-pkg-appimage: release ## Package a test release AppImage
-	installers/appimage/create_appimage.sh meson_release/oolite.app "test"
-
-.PHONY: pkg-appimage-deployment
-pkg-appimage-deployment: release-deployment ## Package a deployment AppImage
-	installers/appimage/create_appimage.sh meson_deployment/oolite.app
-
-.PHONY: pkg-appimage-snapshot
-pkg-appimage-snapshot: release-snapshot ## Package a snapshot AppImage
-	installers/appimage/create_appimage.sh meson_snapshot/oolite.app "dev"
-
-.PHONY: pkg-win
-pkg-win: release ## Package a Windows NSIS test release installer
-	installers/win32/create_nsis.sh meson_release/oolite.app "test"
-
-.PHONY: pkg-win-deployment
-pkg-win-deployment: release-deployment ## Package a Windows NSIS deployment installer
-	installers/win32/create_nsis.sh meson_deployment/oolite.app
-
-.PHONY: pkg-win-snapshot
-pkg-win-snapshot: release-snapshot ## Package a Windows NSIS snapshot installer
-	installers/win32/create_nsis.sh meson_snapshot/oolite.app "dev"
diff --git a/README.md b/README.md
index 44a3ba468..642ccb527 100644
--- a/README.md
+++ b/README.md
@@ -46,7 +46,7 @@ where XXX is a version number. Many Linux package managers support Flatpak so yo
 double click the downloaded file to install it.
 
 The AppImage is named `Oolite_XXX-x86_64.AppImage` where XXX is a version number. Download this
-file to where you would like it stored, make it executable and run, for example by typing
+file to where you would like it stored, ./mk.sh it executable and run, for example by typing
 
 ```bash
 chmod +x Oolite_XXX-x86_64.AppImage
@@ -122,54 +122,81 @@ default, but you can supply a further argument to specify an alternative like do
 
 ### Building Oolite
 
-Next run this in your Bash or MSYS2 prompt to build Oolite:
+The underlying build system is Meson, but it is recommended to build via the mk.sh script which also allow you to pass
+meson setup, compile, configure and install flags. Type the following for help:
 
 ```bash
-ShellScripts/common/build_oolite.sh release
+./mk.sh help
 ```
 
-The completed build (executable and games files) can be found in the oolite.app directory.
+Oolite has various build types:
 
-Subsequently, you can clean and build as follows:
+- **"dev"**: Keeps debug symbols in the binary.
+- **"deployment"**: Intended for production builds. Removes debug symbols from the binary, but makes them available in
+  a separate symbols file.
+- **"test"**: Used for test releases; supports the debug console, which expansion developers use to debug their OXPs.
+  Removes debug symbols from the binary, but makes them available in a separate symbols file.
+
+You can run this in your Bash or MSYS2 prompt to build Oolite for development:
 
 ```bash
-make clean
-make release
+./mk.sh build dev
 ```
 
-You can run a test from your Bash or MSYS2 prompt as follows:
+Optionally you can pass `--setup-flags` and/or `--compile-flags` to pass specific options to meson. The completed build 
+(executable and games files) can be found in the `build/meson_dev/oolite.app` directory.
+
+build dev runs 2 actions which can be run independently: `setup dev` which runs meson setup and `compile dev` which runs
+meson compile.
+
+If for some reason the build fails, you can try cleaning the build folder first, although meson should not usually
+require this step:
 
 ```bash
-make test
+./mk.sh clean dev
 ```
 
-Other targets are release-deployment for a production release and release-snapshot for a debug release.
+You can run a test of the development build that launches the game and takes a snapshot from your Bash or MSYS2 prompt 
+as follows:
 
+```bash
+./mk.sh test dev
+```
 
+You can modify build options of the build directory (such as `--prefix`):
 
-### Other Linux Make Targets
+```bash
+./mk.sh configure dev --configure-flags="<FLAGS>"
+```
 
-This target builds an AppImage for testing which can be found in build:
+You can install the build folder:
 
 ```bash
-make pkg-appimage
+./mk.sh install dev
 ```
 
-The target pkg-appimage-deployment is the production release, while pkg-appimage-snapshot is for debugging.
+Optionally you can pass `--install-flags` to pass specific options to meson.
 
-This target builds a Flatpak which can be found in build:
+### Other Linux ./mk.sh Actions
+
+This action builds an AppImage for development which can be found in the `build` folder:
+
+```bash
+./mk.sh pkg-appimage dev
+```
+
+This action builds a Flatpak which can be found in the `build` folder:
 
 ```bash
-make pkg-flatpak
+./mk.sh pkg-flatpak deployment
 ```
 
-Although there is a top level Makefile, the underlying build system is Meson. You can run the deployment
-build directly using Meson build commands like this:
+### Other Windows ./mk.sh Actions
+
+This action builds a Windows NSIS installer for development which can be found in the `build` folder:
 
 ```bash
-meson setup build/meson_deployment -Ddeployment_release_configuration=true -Ddebug=false -Dstrip_bin=true -Db_lto=true --native-file clang.ini --reconfigure
-meson compile -C build/meson_deployment
-meson install -C build/meson_deployment
+./mk.sh pkg-win dev
 ```
 
 ### Mac OS
@@ -196,7 +223,7 @@ guide to the source tree.
 - **ShellScripts**:  Scripts to build from source on Windows and Linux
 - **installers**:  Files used to create various installers
 - **Resources**:  Game assets and resource files for Mac and GNUstep application bundles
-- **Schemata**:  Plist schema files for the [OXP Verifier](http://wiki.alioth.net/index.php/OXP_howto#OXP_Verifier)
+    - **Schemata**:  Plist schema files for the [OXP Verifier](http://wiki.alioth.net/index.php/OXP_howto#OXP_Verifier)
 - **src**:  Objective-C and C sources, incuding header files
     - **Cocoa**:  Files that are only compiled on Mac OS X
     - **Core**:  Files that are compiled on all platforms
diff --git a/ShellScripts/Linux/build_gnustep.sh b/ShellScripts/Linux/build_gnustep.sh
index d98b1457f..c8771cc41 100755
--- a/ShellScripts/Linux/build_gnustep.sh
+++ b/ShellScripts/Linux/build_gnustep.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 # Parameter one: "system", "home", or "build" (defaults to home).
-# Parameter two: Escalate command (defaults to sudo for 'system').
+# Parameter two: escalate command (defaults to sudo for 'system').
 
 run_script() {
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
@@ -9,7 +9,8 @@ run_script() {
     echo "Building GNUStep libraries"
 
     source dep_location_fn.sh
-    dep_location LIB_SUBDIR TARGET ESCALATE "gnustep" $1 $2
+    local lib_subdir target escalate
+    dep_location lib_subdir target escalate "gnustep" $1 $2
 
 
     mkdir -p ../../build
@@ -52,7 +53,7 @@ run_script() {
     rm -rf build
     mkdir build
     cd build
-    if ! cmake -DCMAKE_INSTALL_PREFIX="$TARGET" -DCMAKE_INSTALL_LIBDIR="$LIB_SUBDIR" -DTESTS=on -DCMAKE_BUILD_TYPE=Release -DGNUSTEP_INSTALL_TYPE=NONE -DEMBEDDED_BLOCKS_RUNTIME=ON -DOLDABI_COMPAT=OFF ../; then
+    if ! cmake -DCMAKE_INSTALL_PREFIX="$target" -DCMAKE_INSTALL_LIBDIR="$lib_subdir" -DTESTS=on -DCMAKE_BUILD_TYPE=Release -DGNUSTEP_INSTALL_TYPE=NONE -DEMBEDDED_BLOCKS_RUNTIME=ON -DOLDABI_COMPAT=OFF ../; then
         echo "❌ libobjc2 cmake configure failed!" >&2
         return 1
     fi
@@ -61,29 +62,29 @@ run_script() {
         echo "❌ libobjc2 cmake build failed!" >&2
         return 1
     fi
-    $ESCALATE cmake --install .
+    $escalate cmake --install .
     cd ../..
 
     cd tools-make
     make clean
 
-    local lib_dir="$TARGET/$LIB_SUBDIR"
-    export CPPFLAGS="-I$TARGET/include"
+    local lib_dir="$target/$lib_subdir"
+    export CPPFLAGS="-I$target/include"
     export LDFLAGS="-L$lib_dir"
 
-    if ! ./configure --prefix="$TARGET" --with-library-combo=ng-gnu-gnu --with-runtime-abi=gnustep-2.2 "--with-libdir=$LIB_SUBDIR"; then
+    if ! ./configure --prefix="$target" --with-library-combo=ng-gnu-gnu --with-runtime-abi=gnustep-2.2 "--with-libdir=$lib_subdir"; then
         echo "❌ tools-make configure failed!" >&2
         return 1
     fi
     make
-    $ESCALATE make install
+    $escalate make install
     cd ..
 
     cd libs-base
     make clean
 
     export LD_LIBRARY_PATH="$lib_dir:$LD_LIBRARY_PATH"
-    source "$TARGET/share/GNUstep/Makefiles/GNUstep.sh"
+    source "$target/share/GNUstep/Makefiles/GNUstep.sh"
     if ! ./configure; then
         echo "❌ libs-base configure failed!" >&2
         return 1
@@ -92,7 +93,7 @@ run_script() {
         echo "❌ libs-base make failed!" >&2
         return 1
     fi
-    $ESCALATE make install
+    $escalate make install
 
     popd
 }
diff --git a/ShellScripts/Linux/install_freedesktop_fn.sh b/ShellScripts/Linux/install_freedesktop_fn.sh
deleted file mode 100644
index b3a66a81c..000000000
--- a/ShellScripts/Linux/install_freedesktop_fn.sh
+++ /dev/null
@@ -1,71 +0,0 @@
-#!/bin/bash -x
-#
-# Installs the manifest and injects version number
-#
-# Requires environment variables:
-#   VERSION
-#   APP_DATE
-#
-
-echo "I am install_freedesktop_fn.sh $@"
-printenv | sort
-
-install_freedesktop() {
-    # Install metainfo (eg. for FlatHub and AppImageHub)
-    # $1: oolite.app directory path (source)
-    # $2: app folder (destination)
-    # $3: debug symbol folder
-    # $4: appdata or metainfo
-
-    local err_msg="❌ Error: Failed to"
-
-    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
-    pushd "$script_dir"
-
-    source ../common/get_version.sh
-
-    echo "Installing metainfo to to $2"
-
-    local appbin="$2/bin"
-    local appshr="$2/share"
-
-    # Install binaries and scripts
-    install -D "$1/oolite" "$appbin/oolite" || { echo "$err_msg install oolite binary" >&2; return 1; }
-    if [[ -f "$1/oolite.debug" ]]; then
-        install -D "$1/oolite.debug" "$2/$3/oolite.debug" || { echo "$err_msg install oolite debug symbols" >&2; return 1; }
-    fi
-    install -D "$1/run_oolite.sh" "$appbin/run_oolite.sh" || { echo "$err_msg install run_oolite.sh" >&2; return 1; }
-
-    # Resources copy
-    local resourcesdir="$appshr/oolite/Resources"
-    mkdir -p "$resourcesdir"
-    cp -rf "$1/Resources/." "$resourcesdir/" || { echo "$err_msg copy Resources folder" >&2; return 1; }
-
-    # AddOns copy if folder exists in oolite.app
-    if [ -d "$1/AddOns" ]; then
-        local addonsdir="$appshr/oolite/AddOns"
-        mkdir -p "$addonsdir"
-        cp -rf "$1/AddOns/." "$addonsdir/" || { echo "$err_msg copy AddOns folder" >&2; return 1; }
-    fi
-
-    rm -f "$resourcesdir/GNUstep.conf.orig"
-    install -D "GNUstep.conf.template" "$resourcesdir/GNUstep.conf.template" || { echo "$err_msg GNUstep template" >&2; return 1; }
-
-    local app_metainfo="$appshr/metainfo/space.oolite.Oolite.$4.xml"
-    install -D ../../installers/FreeDesktop/space.oolite.Oolite.metainfo.xml.template "$app_metainfo" || { echo "$err_msg metainfo template" >&2; return 1; }
-
-    sed -i "s/@VER@/${VER_FULL}/g" "$app_metainfo"
-    sed -i "s/@DATE@/${APP_DATE}/g" "$app_metainfo"
-
-    echo ===========================================
-    echo Our manifest looks like this:
-    cat "$app_metainfo"
-    echo ===========================================
-
-    # Desktop and Icon
-    install -D ../../installers/FreeDesktop/space.oolite.Oolite.desktop "$appshr/applications/space.oolite.Oolite.desktop" || { echo "$err_msg desktop file" >&2; return 1; }
-
-    install -D "$1/Resources/Textures/oolite-logo1.png" "$appshr/icons/hicolor/256x256/apps/space.oolite.Oolite.png" || { echo "$err_msg icon file" >&2; return 1; }
-
-    popd
-}
\ No newline at end of file
diff --git a/ShellScripts/Linux/install_gitversion_fn.sh b/ShellScripts/Linux/install_gitversion_fn.sh
new file mode 100644
index 000000000..62d761cb2
--- /dev/null
+++ b/ShellScripts/Linux/install_gitversion_fn.sh
@@ -0,0 +1,23 @@
+install_gitversion() {
+    local outputdir="$1"
+
+    # If current user ID is NOT 0 (root)
+    if [[ $EUID -ne 0 ]]; then
+        echo "This script requires root to install dependencies. Rerun and escalate privileges (eg. sudo ...)"
+        return 1
+    fi
+
+    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
+    pushd "$script_dir"
+
+    source ../common/download_github_release_fn.sh
+
+    local gitversion_tgz
+    download_github_release gitversion_tgz "GitTools" "GitVersion" "linux-x64" "$outputdir"
+    tar xfz ${gitversion_tgz} --directory "$outputdir"
+    chmod +x "$outputdir/gitversion"
+    mv "$outputdir/gitversion" /usr/local/bin/gitversion
+    rm -f ${gitversion_tgz}
+
+    popd
+}
\ No newline at end of file
diff --git a/ShellScripts/Linux/install_mozilla_js.sh b/ShellScripts/Linux/install_mozilla_js.sh
index be51a2dea..192e38a95 100755
--- a/ShellScripts/Linux/install_mozilla_js.sh
+++ b/ShellScripts/Linux/install_mozilla_js.sh
@@ -1,19 +1,20 @@
 #!/bin/bash
 # Parameter one: "system", "home", or "build" (defaults to home).
-# Parameter two: Escalate command (defaults to sudo for 'system').
+# Parameter two: escalate command (defaults to sudo for 'system').
 
 run_script() {
     # Get the directory where the script is located
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
 
     source "$script_dir/dep_location_fn.sh"
-    dep_location LIB_SUBDIR TARGET ESCALATE "mozilla_js" $1 $2
+    local lib_subdir target escalate
+    dep_location lib_subdir target escalate "mozilla_js" $1 $2
 
     # The URL to your specific GitHub release asset
     local release_url="https://github.com/OoliteProject/mozillajs-linux/releases/download/0.0.1/mozilla-js-static-lib.tar.gz"
 
-    echo "Installing Mozilla JS static library to $TARGET"
-    [[ -n "$ESCALATE" ]] && echo "Using escalation: $ESCALATE"
+    echo "Installing Mozilla JS static library to $target"
+    [[ -n "$escalate" ]] && echo "Using escalation: $escalate"
 
     # Download and extract
     # Curl downloads as current user, Tar extracts using escalation
@@ -32,12 +33,12 @@ run_script() {
     fi
 
     # Move headers to include
-    if ! $ESCALATE cp -r "$temp_staging/include/"* "$TARGET/include/"; then
+    if ! $escalate cp -r "$temp_staging/include/"* "$target/include/"; then
         echo "❌ Mozilla JS library header install failed!" >&2
         return 1
     fi
     # Move libs from 'lib' in tarball to 'lib64' on system
-    if ! $ESCALATE cp -r "$temp_staging/lib/"* "$TARGET/$LIB_SUBDIR/"; then
+    if ! $escalate cp -r "$temp_staging/lib/"* "$target/$lib_subdir/"; then
         echo "❌ Mozilla JS library lib install failed!" >&2
         return 1
     fi
diff --git a/ShellScripts/Linux/install_package_fn.sh b/ShellScripts/Linux/install_package_fn.sh
index affdaa29e..476ad8a43 100644
--- a/ShellScripts/Linux/install_package_fn.sh
+++ b/ShellScripts/Linux/install_package_fn.sh
@@ -15,7 +15,7 @@ install_package() {
         "base-devel")
             case "$CURRENT_DISTRO" in
                 debian) pkg_name="build-essential" ;;
-                redhat) pkg_name="gcc gcc-c++ make" ;;
+                redhat) pkg_name="gcc gcc-c++" ;;
                 arch) pkg_name="base-devel" ;;
             esac ;;
 
diff --git a/ShellScripts/Linux/install_packages_root.sh b/ShellScripts/Linux/install_packages_root.sh
index 5d3672c79..ddd9a31a5 100755
--- a/ShellScripts/Linux/install_packages_root.sh
+++ b/ShellScripts/Linux/install_packages_root.sh
@@ -14,9 +14,8 @@ run_script() {
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir"
 
-    source ../common/download_github_fn.sh
-
-    source ./install_package_fn.sh
+    source install_gitversion_fn.sh
+    source install_package_fn.sh
 
     if ! install_package base-devel; then
         return 1
@@ -101,12 +100,7 @@ run_script() {
     # install gitversion
     local outputdir="../../build"
     mkdir -p "$outputdir"
-    download_latest_release gitversion_tgz "GitTools" "GitVersion" "linux-x64" "$outputdir"
-    tar xfz ${gitversion_tgz} --directory "$outputdir"
-    chmod +x "$outputdir/gitversion"
-    mv "$outputdir/gitversion" /usr/local/bin/gitversion
-    rm -f ${gitversion_tgz}
-
+    install_gitversion "$outputdir"
 	popd
 }
 
diff --git a/ShellScripts/Linux/os_detection.sh b/ShellScripts/Linux/os_detection.sh
index 20e62ab61..8dc20794e 100644
--- a/ShellScripts/Linux/os_detection.sh
+++ b/ShellScripts/Linux/os_detection.sh
@@ -5,7 +5,11 @@
 
 if [ -f /etc/os-release ]; then
     . /etc/os-release
-    OS_FAMILY="${ID} ${ID_LIKE}"
+    if [[ -v ID_LIKE ]]; then
+        OS_FAMILY="${ID} ${ID_LIKE}"
+    else
+        OS_FAMILY="${ID}"
+    fi
 else
     echo "❌ /etc/os-release not found - cannot detect OS!" >&2
     exit 1
diff --git a/ShellScripts/Windows/install_deps.sh b/ShellScripts/Windows/install_deps.sh
index ce6669d84..f9cc4677b 100755
--- a/ShellScripts/Windows/install_deps.sh
+++ b/ShellScripts/Windows/install_deps.sh
@@ -35,7 +35,7 @@ run_script() {
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir"
 
-    source ../common/download_github_fn.sh
+    source ../common/download_github_release_fn.sh
 
     local oolite_deps_url="https://api.github.com/repos/OoliteProject/oolite_windeps_build/releases/latest"
 
@@ -47,7 +47,6 @@ run_script() {
     pacboy -S jq --noconfirm
     pacman -S unzip --noconfirm
     pacboy -S python-pip --noconfirm
-    pacman -S make --noconfirm
     pacboy -S meson --noconfirm
     pacboy -S ninja --noconfirm
     pacboy -S nsis --noconfirm
@@ -59,16 +58,17 @@ run_script() {
     pacboy -S mesa --noconfirm
     pacboy -S sdl3 --noconfirm
 
+    mkdir -p ../../build/packages
     cd ../../build
     # install gitversion
+    local gitversion_zip
     local outputdir="."
-    download_latest_release gitversion_zip "GitTools" "GitVersion" "win-x64" "$outputdir"
+    download_github_release gitversion_zip "GitTools" "GitVersion" "win-x64" "$outputdir"
     unzip -o ${gitversion_zip} -d "$outputdir"
     chmod +x "$outputdir/gitversion.exe"
     mv "$outputdir/gitversion.exe" "$MINGW_PREFIX/bin/gitversion.exe"
     rm -f ${gitversion_zip}
 
-    mkdir -p packages
     cd packages
     curl -s "$oolite_deps_url" | \
     grep -oP '"browser_download_url": "\K[^"]+' | \
diff --git a/ShellScripts/common/build_oolite.sh b/ShellScripts/common/build_oolite.sh
deleted file mode 100755
index b68fc19bc..000000000
--- a/ShellScripts/common/build_oolite.sh
+++ /dev/null
@@ -1,35 +0,0 @@
-#!/bin/bash
-# No parameters: build target = release
-# One parameter: build target
-
-run_script() {
-    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
-    pushd "$script_dir"
-
-    cd ../..
-
-    local target
-    if [[ -z "$1" ]]; then
-        target=release
-    else
-        target=$1
-    fi
-
-    make clean
-    if ! make $target; then
-        echo "❌ Oolite build failed!" >&2
-        return 1
-    fi
-    echo "✅ Oolite build completed successfully"
-
-    popd
-}
-
-run_script "$@"
-status=$?
-
-
-# Exit only if not sourced
-if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
-    exit $status
-fi
\ No newline at end of file
diff --git a/ShellScripts/common/download_github_fn.sh b/ShellScripts/common/download_github_release_fn.sh
similarity index 92%
rename from ShellScripts/common/download_github_fn.sh
rename to ShellScripts/common/download_github_release_fn.sh
index 6b0b95ecd..7abe8c69f 100755
--- a/ShellScripts/common/download_github_fn.sh
+++ b/ShellScripts/common/download_github_release_fn.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
-download_latest_release() {
-    local -n downloaded_file="$1"
+download_github_release() {
+    local -n _downloaded_file="$1"
     local owner="$2"
     local repository="$3"
     local filter="$4"
@@ -39,5 +39,5 @@ download_latest_release() {
     echo "Downloading latest release: ${filename}..." >&2
     curl -L -O --output-dir "${outputdir}" "${download_url}"
 
-    downloaded_file="${outputdir}/${filename}"
+    _downloaded_file="${outputdir}/${filename}"
 }
\ No newline at end of file
diff --git a/ShellScripts/common/generate_manifest_fn.sh b/ShellScripts/common/generate_manifest_fn.sh
index 2fe7a426a..b6e5428ed 100755
--- a/ShellScripts/common/generate_manifest_fn.sh
+++ b/ShellScripts/common/generate_manifest_fn.sh
@@ -1,17 +1,12 @@
 generate_manifest() {
-    # Locate the xcconfig file
-    local oolite_version_file="src/Cocoa/oolite-version.xcconfig"
-
-    if [[ ! -f "$oolite_version_file" ]]; then
-        echo "❌ $oolite_version_file not found!" >&2
-        popd > /dev/null
-        return 1
-    fi
-
-    # Extract definition of $OOLITE_VERSION from the xcconfig
-    source "$oolite_version_file"
-
+    local output_file="$1"
+    local deployment_release="$2"
+    local ver_full="$3"
+    local ver_quad="$4"
+    local ver_githash="$5"
+    local build_time="$6"
     source ShellScripts/common/get_gitremote_fn.sh
+    local git_remote
     get_gitremote git_remote
 
     # Redirect the entire block output into the manifest_output file
@@ -20,21 +15,24 @@ generate_manifest() {
         echo "    title = \"Oolite core\";"
         echo "    identifier = \"org.oolite.oolite\";"
         echo "    "
-        echo "    version = \"$VER_FULL\";"
+        echo "    version = \"$ver_full\";"
+        echo "    version_quad = \"$ver_quad\";"
+        echo "    git_commit_hash = \"$ver_githash\";"
+        echo "    build_time = \"$build_time\";"
         echo "    git_remote_url = \"$git_remote\";"
-        echo "    git_commit_hash = \"$VER_GITHASH\";"
 
-        if [[ "$DEPLOYMENT_RELEASE_CONFIGURATION" == "yes" ]]; then
+        if [[ "$deployment_release" == "yes" ]]; then
             echo "    debug_functionality_support = no;"
         else
             echo "    debug_functionality_support = yes;"
         fi
-
-        echo "    required_oolite_version = \"$OOLITE_VERSION\";"
+        IFS='.' read -r major minor rest <<< "$ver_full"
+        local ver_short="$major.$minor"
+        echo "    required_oolite_version = \"${ver_short}\";"
         echo "    "
         echo "    license = \"GPL 2+ / CC-BY-NC-SA 3.0 - see LICENSE.md for details\";"
         echo "    author = \"Giles Williams, Jens Ayton and contributors\";"
         echo "    information_url = \"https://oolite.space/\";"
         echo "}"
-    } > "$1"
-}
\ No newline at end of file
+    } > "$output_file"
+}
diff --git a/ShellScripts/common/get_build_date_fn.sh b/ShellScripts/common/get_build_date_fn.sh
new file mode 100755
index 000000000..4413809d2
--- /dev/null
+++ b/ShellScripts/common/get_build_date_fn.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+#
+# Calculates the Oolite build date
+#
+
+SUITE_PARENT=$(basename "${BASH_SOURCE[1]}")  # Get the name of the script that is sourcing this file
+ALLOWED_SCRIPT="get_version.sh"  # Define the ONLY script allowed to source this
+if [[ "$SUITE_PARENT" != "$ALLOWED_SCRIPT" ]]; then
+    echo "❌ This file can only be sourced by $ALLOWED_SCRIPT!" >&2
+    unset SUITE_PARENT ALLOWED_SCRIPT
+    return 1 2>/dev/null || exit 1
+fi
+unset SUITE_PARENT ALLOWED_SCRIPT
+
+get_build_date() {
+    local -n _cpp_date="$1"
+    local -n _app_date="$2"
+    local -n _buildtime="$3"
+    local -n _builder="$4"
+    local buildtime="$5"
+
+
+    if [[ -z "$buildtime" ]]; then
+        local getversion_timestamp=$(git log -1 --format=%ct)
+        _buildtime=$(date -u -d "@$getversion_timestamp" "+%Y.%m.%d %H:%M")
+    else
+        _buildtime="$buildtime"
+    fi
+
+    local clean_date="${_buildtime//./-}"
+    _cpp_date=$(date -u -d "$clean_date" +"%b%e %Y")
+    _app_date=$(date -u -d "$clean_date" +"%Y-%m-%d")
+
+    if [[ "$GITHUB_REPOSITORY" == "OoliteProject/oolite" ]]; then
+        _builder="OoliteProject"
+    else
+        _builder="unknown"
+    fi
+}
\ No newline at end of file
diff --git a/ShellScripts/common/get_gitremote_fn.sh b/ShellScripts/common/get_gitremote_fn.sh
index 932a7d8b5..0694be38f 100644
--- a/ShellScripts/common/get_gitremote_fn.sh
+++ b/ShellScripts/common/get_gitremote_fn.sh
@@ -1,6 +1,6 @@
 get_gitremote() {
     # Accept a variable name as the first argument to use as a nameref return
-    local -n final_url=$1
+    local -n _final_url=$1
 
     local raw_url resolved_git_dir upstream_url
 
@@ -21,12 +21,12 @@ get_gitremote() {
 
         # If we successfully found an upstream URL, use it.
         if [[ -n "$upstream_url" ]]; then
-            final_url="$upstream_url"
+            _final_url="$upstream_url"
         else
-            final_url="UNKNOWN"
+            _final_url="UNKNOWN"
         fi
     else
         # It's already a standard web URL (GitHub, GitLab, etc.)
-        final_url="$raw_url"
+        _final_url="$raw_url"
     fi
 }
\ No newline at end of file
diff --git a/ShellScripts/common/get_version.sh b/ShellScripts/common/get_version.sh
index 66f241dac..f774abcfa 100755
--- a/ShellScripts/common/get_version.sh
+++ b/ShellScripts/common/get_version.sh
@@ -1,58 +1,127 @@
 #!/bin/bash
 #
-# Calculates the Oolite version number if not passed via env variables. Output goes to stdout.
+# Calculates the Oolite version number and build dates
 #
 
-SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
-pushd "$SCRIPT_DIR" > /dev/null
 
-mkdir -p ../../build
-cd ../../build
-
-# Timestamp of last commit/push
-if [[ -z "${GETVERSION_TIMESTAMP}" ]]; then
-    # Run timestamp exactly once and export it for any subsequent child scripts
-    export GETVERSION_TIMESTAMP=$(git log -1 --format=%ct)
+if [[ -v MINGW_PREFIX ]]; then
+    WIN_PID=$(ps -p $$ | awk 'NR>1 {print $4}')
+    PARENT_PROCESS=$(powershell.exe -Command "
+        \$parentId = (gwmi Win32_Process -Filter 'ProcessId = $WIN_PID').ParentProcessId
+        if (\$parentId) {
+            Write-Output (gwmi Win32_Process -Filter \"ProcessId = \$parentId\").Name
+        }
+    " 2>/dev/null | tr -d '\r')
+    if [ "$PARENT_PROCESS" = "python.exe" ] && ps | grep -q "meson"; then
+        PARENT_PROCESS="meson"
+    fi
+else
+    PARENT_PROCESS=$(ps -p $PPID -o comm= 2>/dev/null || true)
 fi
-# Date conversions use UTC for consistency
-# Convert to __DATE__ format (e.g., Feb 20 2026)
-CPP_DATE=$(date -u -d "@$GETVERSION_TIMESTAMP" +"%b %e %Y")
-# Convert to YYYY-MM-DD
-APP_DATE=$(date -u -d "@$GETVERSION_TIMESTAMP" +"%Y-%m-%d")
-# Convert to YYMMDD format (e.g., 260313)
-VER_DATE=$(date -u -d "@$GETVERSION_TIMESTAMP" +"%y%m%d")
-# Convert to YYYY.MM.DD HH:MM format (e.g., 2026.06.21 07:56)
-BUILDTIME=$(date -u -d "@$GETVERSION_TIMESTAMP" "+%Y.%m.%d %H:%M")
-
-if [[ -z "${VER_FULL}" ]]; then
-    if [[ -z "${GITVERSION_JSON}" ]]; then
-        # Run GitVersion exactly once and export it for any subsequent child scripts
-        if ! command -v gitversion &> /dev/null; then
-            echo "❌ gitversion binary not found!" >&2
-            exit 1
+if [[ "$PARENT_PROCESS" != "meson" ]] || [[ -z "$MESON_BUILD_ROOT" ]]; then
+    SUITE_PARENT=$(basename "${BASH_SOURCE[1]}")  # Get the name of the script that is sourcing this file
+    ALLOWED_SCRIPT="create_flatpak_fn.sh"  # Define the ONLY script allowed to source this
+    if [[ "$SUITE_PARENT" != "$ALLOWED_SCRIPT" ]]; then
+        echo "❌ Parent process is $PARENT_PROCESS, Bash parent is $SUITE_PARENT. This file can only be called by meson or sourced by $ALLOWED_SCRIPT!" >&2
+        unset SUITE_PARENT ALLOWED_SCRIPT
+        return 1 2>/dev/null || exit 1
+    fi
+    unset SUITE_PARENT ALLOWED_SCRIPT
+fi
+
+
+run_script() {
+    local build_dir="$1"  # Input string arguments
+
+    if [[ -z "$build_dir" ]]; then
+        echo "❌ build_dir argument is required!" >&2
+        return 1
+    fi
+
+    source "ShellScripts/common/get_build_date_fn.sh"
+    local output_ver_githash=$(git rev-parse --short=7 HEAD)
+    local dirty_suffix=""
+    git diff --quiet || dirty_suffix="-dirty"
+    local lookup_hash="${output_ver_githash}${dirty_suffix}"
+    local output_ver_full=""
+    local output_buildtime=""
+    local version_file="$build_dir/.meson_version"
+    if [[ -z "${VER_FULL-}" ]]; then
+        if [[ -f "$version_file" ]]; then  # Check if cache exists and has a matching hash context
+            local githash ver_full ver_quad ver_gitrev cpp_date app_date buildtime builder
+            source "$version_file" 2>/dev/null
+            if [[ "$ver_githash" == "$lookup_hash" ]]; then
+                echo "$ver_full"
+                return 0
+            fi
         fi
-        export GITVERSION_JSON=$(gitversion)
+    else
+        output_ver_full="$VER_FULL"
     fi
-    VER_MAJ=$(echo "$GITVERSION_JSON" | jq -r '.Major')
-    VER_MIN=$(echo "$GITVERSION_JSON" | jq -r '.Minor')
-    VER_REV=$(echo "$GITVERSION_JSON" | jq -r '.Patch')
-    if [[ "" == "$VER_REV" ]]; then
-        VER_REV="0"
+
+    if [[ -z "$output_ver_full" ]]; then
+        local exact_tag=""  # Check for an exact Git tag first on a clean tree
+        if [[ -z "$dirty_suffix" ]]; then
+            exact_tag=$(git describe --tags --exact-match HEAD 2>/dev/null)
+        fi
+        if [[ -n "$exact_tag" ]]; then
+            output_ver_full="$exact_tag"
+        else
+            if ! command -v gitversion &> /dev/null; then  # exact tag didn't hit, use gitversion for ver_full
+                echo "❌ gitversion binary not found!" >&2
+                exit 1
+            fi
+            local gitversion_json=$(gitversion)  # Run gitversion and get json output
+            local ver_semver=$(echo "$gitversion_json" | jq -r '.SemVer')
+            if [[ -z "$dirty_suffix" ]]; then
+                output_ver_full="$ver_semver"
+            else
+                local ver_uncommitted=$(echo "$gitversion_json" | jq -r '.UncommittedChanges')
+                output_ver_full="${ver_semver}+dirty.${ver_uncommitted}"
+            fi
+        fi
     fi
-    VER_DIST=$(echo "$GITVERSION_JSON" | jq -r '.VersionSourceDistance')
-    VER_SEMVER=$(echo "$GITVERSION_JSON" | jq -r '.SemVer')
-    VER_UNCOMMITTED=$(echo "$GITVERSION_JSON" | jq -r '.UncommittedChanges')
 
-    if git diff --quiet; then
-        VER_FULL=$VER_SEMVER
+    local clean_ver="${output_ver_full#v}"  # Strip any leading 'v', prerelease tags (-alpha), or build metadata (+)
+    clean_ver="${clean_ver%%-*}"  # Example: "v1.91.0-alpha.1+dirty.3" -> "1.91.0"
+    clean_ver="${clean_ver%%+*}"
+    local ver_maj=$(echo "$clean_ver" | cut -d. -f1)  # Parse out Major, Minor, Patch using standard dot delimiters
+    local ver_min=$(echo "$clean_ver" | cut -d. -f2)
+    local ver_rev=$(echo "$clean_ver" | cut -d. -f3)
+    [[ -z "$ver_rev" ]] && ver_rev="0"
+
+    if [[ -z "$dirty_suffix" ]]; then  # Use git for other metrics for clean repository
+        local closest_tag=$(git describe --tags --abbrev=0 2>/dev/null)  # Derive distance from closest Git tag
+        local ver_dist="0"
+        if [[ -n "$closest_tag" ]]; then
+            ver_dist=$(git rev-list --count "${closest_tag}..HEAD")
+        else
+            ver_dist=$(git rev-list --count HEAD)
+        fi
+        output_ver_quad="$ver_maj.$ver_min.$ver_rev.$ver_dist"
     else
-        VER_FULL="${VER_SEMVER}+dirty.${VER_UNCOMMITTED}"
+        local ver_uncommitted=$(git status --porcelain 2>/dev/null | wc -l)  # Dirty repo: get uncommitted file count
+        output_ver_quad="$ver_maj.$ver_min.$ver_rev.$ver_uncommitted"
     fi
 
-    VER_NSIS="$VER_MAJ.$VER_MIN.$VER_REV.$VER_DIST"
-    VER_GITREV=$(git rev-list --count HEAD)
-    VER_GITHASH=$(git rev-parse --short=7 HEAD)
-fi
+    local output_cpp_date output_app_date output_builder
+    get_build_date output_cpp_date output_app_date output_buildtime output_builder "${BUILDTIME-}"
+
+    cat << EOF > "$version_file"  # Write new values to the hidden cache file
+ver_githash="$lookup_hash"
+ver_full="$output_ver_full"
+ver_quad="$output_ver_quad"
+cpp_date="$output_cpp_date"
+app_date="$output_app_date"
+buildtime="$output_buildtime"
+builder="$output_builder"
+EOF
 
-echo "$VER_FULL"
-popd > /dev/null
+    echo "$output_ver_full"
+}
+
+# Exit only if not sourced
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    run_script "$@"
+    exit $?
+fi
diff --git a/ShellScripts/common/install.sh b/ShellScripts/common/install.sh
index 2b1dd59b6..3f4e3e0fd 100755
--- a/ShellScripts/common/install.sh
+++ b/ShellScripts/common/install.sh
@@ -2,17 +2,28 @@
 # Processes Oolite data files after compilation
 
 run_script() {
+    local stageprogpath="$1"
+    local bindir="$2"
+    local datadir="$3"
+    local host_os="$4"
+    local deployment_release="$5"
+
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir" > /dev/null
 
     cd ../..
 
-    set -x    
-    local appname=$(basename "$STAGEPROGPATH")
-    local progdir=$(dirname "$STAGEPROGPATH")
-    local installdir="${INSTALLDIR:-$MESON_INSTALL_DESTDIR_PREFIX}"
-    local fullbindir="$installdir/$BINDIR"
-    local fulldatadir="$installdir/$DATADIR/oolite"  # don't use appname here as Obj-C has oolite specifically
+    set -x
+    local appname=$(basename "$stageprogpath")
+    local progdir=$(dirname "$stageprogpath")
+    local installdir="$MESON_INSTALL_DESTDIR_PREFIX"
+    local fullbindir="$installdir/$bindir"
+    rm -f "$fullbindir/oolite"
+    if [[ "$host_os" == "linux" ]]; then
+        rm -f "$fullbindir/run_oolite.sh"
+    fi
+    local fulldatadir="$installdir/$datadir/oolite"  # don't use appname here as Obj-C has oolite specifically
+    rm -rf "$fulldatadir"
     local progpath="$fullbindir/$appname"
     if ! mkdir -p "$fullbindir"; then
         echo "❌ Failed to create folder '$fullbindir'!" >&2
@@ -22,17 +33,26 @@ run_script() {
         echo "❌ Failed to create folder '$fulldatadir'!" >&2
         return 1
     fi
-    if ! cp -fu "$STAGEPROGPATH" "$progpath"; then
-        echo "❌ Failed to copy '$STAGEPROGPATH' to '$progpath'!" >&2
+    if ! cp -fu "$stageprogpath" "$progpath"; then
+        echo "❌ Failed to copy '$stageprogpath' to '$progpath'!" >&2
         return 1
-    fi    
-    if [[ "$HOST_OS" == "linux" ]]; then
+    fi
+    if [[ "$host_os" == "linux" ]]; then
         local run_oolite_src="$progdir/run_oolite.sh"
         local run_oolite_dst="$fullbindir/run_oolite.sh"
         if ! cp -fu "$run_oolite_src" "$run_oolite_dst"; then
             echo "❌ Failed to copy '$run_oolite_src' to '$run_oolite_dst'!" >&2
             return 1
         fi
+        local debugname="$appname.debug"
+        local oolite_debug_src="$progdir/$debugname"
+        if [[ -f "$oolite_debug_src" ]]; then
+            local oolite_debug_dst="$fullbindir/$debugname"
+            if ! cp -fu "$oolite_debug_src" "$oolite_debug_dst"; then
+                echo "❌ Failed to copy '$oolite_debug_src' to '$oolite_debug_dst'!" >&2
+                return 1
+            fi
+        fi
     fi
     local resources_src="$progdir/Resources/."
     local resources_dst="$fulldatadir/Resources"
diff --git a/ShellScripts/common/parse_manifest_fn.sh b/ShellScripts/common/parse_manifest_fn.sh
new file mode 100644
index 000000000..8f01e4ff1
--- /dev/null
+++ b/ShellScripts/common/parse_manifest_fn.sh
@@ -0,0 +1,25 @@
+parse_manifest() {
+    local -n _ver_full="$1"
+    local -n _ver_quad="$2"
+    local -n _githash="$3"
+    local -n _buildtime="$4"
+    local -n _app_date="$5"
+    local input_file="$6"
+
+    if [[ ! -f "$input_file" ]]; then  # Ensure the manifest file exists before parsing
+        echo "❌ Manifest file '$input_file' not found." >&2
+        return 1
+    fi
+
+    get_manifest_value() {  # Helper function to extract a string inside quotes for a given key
+        local key="$1"
+        grep -E "^[[:space:]]*${key}[[:space:]]*=" "$input_file" | sed -E 's/.*"[[:space:]]*([^"]*)[[:space:]]*".*/\1/'
+    }
+
+    _ver_full=$(get_manifest_value "version")
+    _ver_quad=$(get_manifest_value "version_quad")
+    _githash=$(get_manifest_value "git_commit_hash")
+    _buildtime=$(get_manifest_value "build_time")
+    local clean_date="${_buildtime//./-}"
+    _app_date=$(date -u -d "${clean_date:0:10}" +"%Y-%m-%d" 2>/dev/null || echo "")
+}
\ No newline at end of file
diff --git a/ShellScripts/common/post_build.sh b/ShellScripts/common/post_build.sh
index eed95d57d..cc6871a1d 100755
--- a/ShellScripts/common/post_build.sh
+++ b/ShellScripts/common/post_build.sh
@@ -2,6 +2,20 @@
 # Processes Oolite data files after compilation
 
 run_script() {
+    local origprogpath="$1"
+    local progdir="$2"
+    local host_os="$3"
+    local debug="$4"
+    local deployment_release="$5"
+    local espeak="$6"
+    local strip_bin="$7"
+    local ver_full="$8"
+    local ver_quad="$9"
+    local ver_githash="${10}"
+    local buildtime="${11}"
+    local gnustep_folder="${12}"
+    local stamp_file="${13}"
+
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir" > /dev/null
 
@@ -9,29 +23,34 @@ run_script() {
     cd ../..
 
     set -x
-    local appname=$(basename "$ORIGPROGPATH")
-    local appdir=$(dirname "$ORIGPROGPATH")
-    local progpath="$PROGDIR/$appname"
-    mkdir -p "$PROGDIR/Resources"
-
-    generate_manifest "$PROGDIR/Resources/manifest.plist"
+    local appname=$(basename "$origprogpath")
+    local appdir=$(dirname "$origprogpath")
+    local progpath="$progdir/$appname"
+    local resourcesdir="$progdir/Resources"
+    mkdir -p "$resourcesdir"
 
-    if [[ ! -f "$ORIGPROGPATH" ]]; then
-        echo "❌ 'Oolite binary at '$ORIGPROGPATH' does not exist!" >&2
+    if [[ ! -f "$origprogpath" ]]; then
+        echo "❌ 'Oolite binary at '$origprogpath' does not exist!" >&2
         return 1
     fi
-    if ! cp -fu "$ORIGPROGPATH" "$progpath"; then
-        echo "❌ Failed to copy '$ORIGPROGPATH' to '$progpath'!" >&2
+    if ! cp -fu "$origprogpath" "$progpath"; then
+        echo "❌ Failed to copy '$origprogpath' to '$progpath'!" >&2
         return 1
     fi
-    cp -fu "$ORIGPROGPATH" "$progpath"
-    cp -fu src/Cocoa/Info-Oolite.plist "$PROGDIR/Resources/Info-gnustep.plist"
+    generate_manifest "$resourcesdir/manifest.plist" "$deployment_release" "$ver_full" "$ver_quad" "$ver_githash" "$buildtime"
+    cp -fu src/Cocoa/Info-Oolite.plist "$resourcesdir/Info-gnustep.plist"
+    if [[ "$deployment_release" == "no" ]]; then
+        local addonsdir="$progdir/AddOns"
+        mkdir -p "$addonsdir"
+        rm -rf "$addonsdir/Basic-debug.oxp"
+        cp -rf DebugOXP/Debug.oxp "$addonsdir/Basic-debug.oxp"
+    fi
 
     # Voice Data
-    if [[ "$ESPEAK" == "yes" ]]; then
-        if [[ "$HOST_OS" == "windows" ]]; then
+    if [[ "$espeak" == "yes" ]]; then
+        if [[ "$host_os" == "windows" ]]; then
             # Windows espeak-ng-data
-            cp -rfu "$MINGW_PREFIX/share/espeak-ng-data" "$PROGDIR/Resources"
+            cp -rfu "$MINGW_PREFIX/share/espeak-ng-data" "$resourcesdir"
         else
             # Linux search paths for espeak-ng-data
             local SEARCH_PATHS=(
@@ -44,7 +63,7 @@ run_script() {
             local path
             for path in "${SEARCH_PATHS[@]}"; do
                 if [[ -d "$path" ]]; then
-                    cp -rfu "$path" "$PROGDIR/Resources"
+                    cp -rfu "$path" "$resourcesdir"
                     found_data=true
                     break
                 fi
@@ -59,19 +78,19 @@ run_script() {
     fi
 
     # Replace specific voices with Oolite-specific versions
-    rm -f "$PROGDIR/Resources/espeak-ng-data/voices/!v/f2"
-    rm -f "$PROGDIR/Resources/espeak-ng-data/voices/default"
-    cp -rfu Resources/. "$PROGDIR/Resources"
-    rm -f "$PROGDIR/Resources/AIReference.html" "$PROGDIR/Resources/*.icns"
+    rm -f "$resourcesdir/espeak-ng-data/voices/!v/f2"
+    rm -f "$resourcesdir/espeak-ng-data/voices/default"
+    cp -rfu Resources/. "$resourcesdir"
+    rm -f "$resourcesdir/AIReference.html" "$resourcesdir/*.icns"
 
     # Strip binary if requested
-    if [[ "$STRIP_BIN" == "yes" ]]; then
-        if [[ "$HOST_OS" == "windows" ]]; then
+    if [[ "$strip_bin" == "yes" ]]; then
+        if [[ "$host_os" == "windows" ]]; then
             # Windows: Standard GNU strip is safest for PE/COFF
             strip "$progpath"
         else
             # Linux
-            local debugpath="$PROGDIR/$appname.debug"
+            local debugpath="$progdir/$appname.debug"
             # Extract symbols to file
             objcopy --only-keep-debug "$progpath" "$debugpath"
             # Compress the debug sections in the symbol file
@@ -81,34 +100,34 @@ run_script() {
             # Add the debug link
             objcopy --add-gnu-debuglink="$debugpath" "$progpath"
         fi
-    elif [[ "$HOST_OS" == "linux" ]]; then
+    elif [[ "$host_os" == "linux" ]]; then
         # Compress the debug sections in the binary
         objcopy --compress-debug-sections=zlib-gnu "$progpath"
     fi
 
-    if [[ "$HOST_OS" == "windows" ]]; then
+    if [[ "$host_os" == "windows" ]]; then
         # Determine and copy DLL dependencies
         local unix_prefix=$(cygpath -u "$MINGW_PREFIX")
-        ldd "$progpath" | grep "$unix_prefix" | awk '{print $3}' | xargs -I {} cp -rfu {} "$PROGDIR"
+        ldd "$progpath" | grep "$unix_prefix" | awk '{print $3}' | xargs -I {} cp -rfu {} "$progdir"
     else
         # Copy Linux-specific wrapper script
-        cp -fu ShellScripts/Linux/run_oolite.sh "$PROGDIR"
-        local gnustep_conf="$GNUSTEP_FOLDER/etc/GNUstep/GNUstep.conf"
-        if [ ! -f "$gnustep_conf" ] && [ "$GNUSTEP_FOLDER" = "/usr" ] && [ -f "/etc/GNUstep/GNUstep.conf" ]; then
+        cp -fu ShellScripts/Linux/run_oolite.sh "$progdir"
+        local gnustep_conf="$gnustep_folder/etc/GNUstep/GNUstep.conf"
+        if [ ! -f "$gnustep_conf" ] && [ "$gnustep_folder" = "/usr" ] && [ -f "/etc/GNUstep/GNUstep.conf" ]; then
             gnustep_conf="/etc/GNUstep/GNUstep.conf"
         fi
-        install -D "$gnustep_conf" "$PROGDIR/Resources/GNUstep.conf.orig" || { echo "$err_msg GNUstep config" >&2; return 1; }
+        install -D "$gnustep_conf" "$resourcesdir/GNUstep.conf.orig" || { echo "$err_msg GNUstep config" >&2; return 1; }
 
         # If we're using GNUstep libraries that aren't in a system folder copy them
         ldd "$progpath" | \
             grep -E "libgnustep-base|libobjc\.so\." | \
             grep -vE "^[[:space:]]*.*=>[[:space:]]*/(usr/(local/)?|lib(64)?/)" | \
             awk '{print $3}' | \
-            xargs -I {} cp -Lrfu {} "$PROGDIR/"
+            xargs -I {} cp -Lrfu {} "$progdir/"
     fi
 
     echo "✅ Oolite post-build completed successfully"
-    touch "$appdir/$STAMP_FILE"
+    touch "$appdir/$stamp_file"
     popd > /dev/null
 }
 
@@ -118,4 +137,4 @@ status=$?
 # Exit only if not sourced
 if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
     exit $status
-fi
\ No newline at end of file
+fi
diff --git a/ShellScripts/Linux/GNUstep.conf.template b/installers/FreeDesktop/GNUstep.conf.template
similarity index 100%
rename from ShellScripts/Linux/GNUstep.conf.template
rename to installers/FreeDesktop/GNUstep.conf.template
diff --git a/installers/FreeDesktop/install_freedesktop_fn.sh b/installers/FreeDesktop/install_freedesktop_fn.sh
new file mode 100644
index 000000000..b6d11f959
--- /dev/null
+++ b/installers/FreeDesktop/install_freedesktop_fn.sh
@@ -0,0 +1,42 @@
+#!/bin/bash -x
+#
+# Installs the manifest and injects version number
+
+
+install_freedesktop() {
+    local -n output_ver_full="$1"  # Oolite version
+    local build_folder="$2"  # oolite.app directory path (source)
+    local app_folder="$3"  # app folder (destination)
+    local symbol_folder="$4"  # debug symbol folder
+    local metainfo_suffix="$5"  # can be appdata or metainfo
+
+    local err_msg="❌ Error: Failed to install"
+
+    source ../../ShellScripts/common/parse_manifest_fn.sh
+
+    echo "Installing metainfo to $app_folder"
+
+    local ver_quad githash buildtime app_date
+    parse_manifest output_ver_full ver_quad githash buildtime app_date "$build_folder/Resources/manifest.plist"
+
+    local freedesktopdir="../../installers/FreeDesktop"
+    local appshr="$app_folder/share"
+    local resourcesdir="$appshr/oolite/Resources"
+    rm -f "$resourcesdir/GNUstep.conf.orig"
+    install -D "$freedesktopdir/GNUstep.conf.template" "$resourcesdir/GNUstep.conf.template" || { echo "$err_msg GNUstep template" >&2; return 1; }
+
+    local app_metainfo="$appshr/metainfo/space.oolite.Oolite.$metainfo_suffix.xml"
+    install -D "$freedesktopdir/space.oolite.Oolite.metainfo.xml.template" "$app_metainfo" || { echo "$err_msg metainfo template" >&2; return 1; }
+
+    sed -i "s/@VER@/${output_ver_full}/g" "$app_metainfo"
+    sed -i "s/@DATE@/${app_date}/g" "$app_metainfo"
+
+    echo ===========================================
+    echo Our manifest looks like this:
+    cat "$app_metainfo"
+    echo ===========================================
+
+    # Desktop and Icon
+    install -D "$freedesktopdir/space.oolite.Oolite.desktop" "$appshr/applications/space.oolite.Oolite.desktop" || { echo "$err_msg desktop file" >&2; return 1; }
+    install -D "$build_folder/Resources/Textures/oolite-logo1.png" "$appshr/icons/hicolor/256x256/apps/space.oolite.Oolite.png" || { echo "$err_msg icon file" >&2; return 1; }
+}
\ No newline at end of file
diff --git a/installers/appimage/create_appimage.sh b/installers/appimage/create_appimage_fn.sh
similarity index 76%
rename from installers/appimage/create_appimage.sh
rename to installers/appimage/create_appimage_fn.sh
index e81c99d75..92a827287 100755
--- a/installers/appimage/create_appimage.sh
+++ b/installers/appimage/create_appimage_fn.sh
@@ -1,32 +1,24 @@
 #!/bin/bash -x
 #
 # Creates the appimage.
-# First parameter can be set to build type, typically one of "test", "dev" or omitted for release builds.
-#
 
-echo I am $0 $@
+create_appimage() {
+    local build_type="$1"  # Typically one of "deployment", "test", "dev"
+    local build_folder="$2"  # Build folder
 
-run_script() {
-    # First parameter is a suffix for the build type eg. test, dev
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir"
+    source ../FreeDesktop/install_freedesktop_fn.sh
+    source ../../ShellScripts/Linux/os_detection.sh
 
-    mkdir -p ../../build
-    cd ../../build
-    source ../ShellScripts/Linux/os_detection.sh
-    source ../ShellScripts/common/get_version.sh
-    source ../ShellScripts/Linux/install_freedesktop_fn.sh
-
+    cd ../../build/appimage
     local arch=$(uname -m)
     local APPDIR="./oolite.AppDir"
     export APPDIR
     local appbin="$APPDIR/bin"
     local appshr="$APPDIR/share"
-    rm -rf "$APPDIR"
 
-    local abs_oolitedir=$(realpath -m "$1")
-    local abs_appdir=$(realpath -m "$APPDIR")
-    if ! install_freedesktop "$abs_oolitedir" "$abs_appdir" bin appdata; then
+    if ! install_freedesktop ver_full "../$build_folder" "$APPDIR" "bin" "appdata"; then
         return 1
     fi
 
@@ -44,10 +36,10 @@ run_script() {
     local DESKTOP="$appshr/applications/space.oolite.Oolite.desktop"
     export DESKTOP
     local suffix
-   	if (( $# == 2 )); then
-        suffix="_${2}-${VER_FULL}"
+    if [[ "$build_type" != "deployment" ]]; then
+        suffix="_$build_type-$ver_full"
     else
-        suffix="-$VER_FULL"
+        suffix="-$ver_full"
     fi
     local OUTNAME="oolite${suffix}-${arch}.AppImage"
     export OUTNAME
@@ -94,20 +86,10 @@ run_script() {
     fi
 
     echo "Creating AppImage $OUTNAME..."
-    if ! $appimagetool_bin "$abs_appdir" "$OUTNAME"; then
+    if ! $appimagetool_bin "$APPDIR" "../$OUTNAME"; then
         echo "❌ AppImage creation failed!" >&2
         return 1
     fi
 
     popd
 }
-
-run_script "$@"
-status=$?
-
-
-# Exit only if not sourced
-if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
-    exit $status
-fi
-
diff --git a/installers/flatpak/create_flatpak.sh b/installers/flatpak/create_flatpak.sh
deleted file mode 100755
index 0ded5d34b..000000000
--- a/installers/flatpak/create_flatpak.sh
+++ /dev/null
@@ -1,139 +0,0 @@
-#!/bin/bash -x
-
-echo "I am $0 $@"
-
-run_script() {
-    # First parameter is a suffix for the build type eg. test, dev
-    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
-    pushd "$script_dir"
-
-    cd ../..
-    mkdir -p build
-    cd build
-    if ! command -v gitversion &> /dev/null; then
-        echo "Installing gitversion..."
-        source ../ShellScripts/common/download_github_fn.sh
-        local outputdir="."
-        download_latest_release gitversion_tgz "GitTools" "GitVersion" "linux-x64" "$outputdir"
-        tar xfz ${gitversion_tgz} --directory "$outputdir"
-        chmod +x "$outputdir/gitversion"
-        mkdir -p /usr/local/bin
-        mv "$outputdir/gitversion" /usr/local/bin/gitversion
-        rm -f ${gitversion_tgz}
-    fi
-    source ../ShellScripts/common/get_version.sh
-
-    cp ../installers/flatpak/space.oolite.Oolite.* ./
-
-    mkdir -p shared-modules/glu
-    if ! curl -o shared-modules/glu/glu-9.json -L https://github.com/flathub/shared-modules/raw/refs/heads/master/glu/glu-9.json; then
-        echo "❌ Flatpak download of glu shared module failed!" >&2
-        return 1
-    fi
-
-    local manifest="space.oolite.Oolite.yaml"
-
-    local env_block="env:\n        VER_FULL: \"$VER_FULL\"\n        GITHUB_REPOSITORY: \"$GITHUB_REPOSITORY\""
-    # Swap the comment
-    sed -i "s|#[[:space:]]*CI builds add an env block here|$env_block|g" "$manifest" || return 1
-
-    # check manifest
-    local lint_exceptions=$(mktemp /tmp/oolite-lint-XXXXXX.json)
-    cat <<EOF > "$lint_exceptions"
-{
-  "space.oolite.Oolite": [
-    "finish-args-has-dev-input"
-  ]
-}
-EOF
-    trap 'rm -f "$lint_exceptions"' RETURN EXIT
-
-    if command -v flatpak-builder-lint >/dev/null 2>&1; then
-        if ! flatpak-builder-lint manifest "$manifest" --exceptions --user-exceptions="$lint_exceptions"; then
-            echo "❌ Flatpak manifest lint failed!" >&2
-            cat "$manifest"
-            echo "❌ Flatpak manifest lint failed!" >&2
-            return 1
-        fi
-    else
-        echo "Native linter not found. Falling back to Flatpak container..."
-        if ! flatpak run --filesystem="$lint_exceptions" --command=flatpak-builder-lint org.flatpak.Builder manifest "$manifest" --exceptions --user-exceptions="$lint_exceptions"; then
-            echo "❌ Flatpak manifest lint failed!" >&2
-            return 1
-        fi
-    fi
-
-    # 3. Clean up
-    rm -f "$lint_exceptions"
-    trap - RETURN EXIT
-
-    echo "Creating Flatpak..."
-    if ! flatpak remote-add \
-      --user \
-      --if-not-exists \
-      flathub https://flathub.org/repo/flathub.flatpakrepo; then
-        echo "❌ Flatpak adding Flathub remote failed!" >&2
-        return 1
-    fi
-
-    local total_lines=$(wc -l < $manifest)
-    local start_line=$((total_lines - 3))
-    sed -i "${start_line},\$d" $manifest
-    cat <<EOF >> $manifest
-      - type: dir
-        path: ../
-EOF
-
-    # show effective manifest
-    flatpak-builder --show-manifest $manifest
-
-    if ! flatpak-builder \
-      --user \
-      --force-clean \
-      --repo=repo \
-      --install-deps-from=flathub \
-      --disable-rofiles-fuse \
-      build-dir \
-      $manifest; then
-        echo "❌ Flatpak build failed!" >&2
-        return 1
-    fi
-
-    local suffix
-   	if (( $# == 1 )); then
-        suffix="_${1}-${VER_FULL}"
-    else
-        suffix="-$VER_FULL"
-    fi
-    local ARCH=$(uname -m)
-    local filename="space.oolite.Oolite${suffix}-${ARCH}.flatpak"
-    echo "Creating Flatpak $filename..."
-    if ! flatpak build-bundle \
-      repo \
-      "$filename" \
-      space.oolite.Oolite; then
-        echo "❌ Flatpak bundle creation failed!" >&2
-        return 1
-    fi
-    local debugname="space.oolite.Oolite.Debug${suffix}-${ARCH}.flatpak"
-    if ! flatpak build-bundle \
-      --runtime \
-      repo \
-      "$debugname" \
-      space.oolite.Oolite.Debug; then
-        echo "❌ Flatpak bundle creation failed!" >&2
-        return 1
-    fi
-
-    popd
-}
-
-run_script "$@"
-status=$?
-
-
-# Exit only if not sourced
-if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
-    exit $status
-fi
-
diff --git a/installers/flatpak/create_flatpak_fn.sh b/installers/flatpak/create_flatpak_fn.sh
new file mode 100755
index 000000000..0ce28358a
--- /dev/null
+++ b/installers/flatpak/create_flatpak_fn.sh
@@ -0,0 +1,121 @@
+#!/bin/bash -x
+
+create_flatpak() {
+    local build_type="$1"
+    local github_repository="$2" # GitHub repository (set by GitHub Actions)
+
+    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
+    pushd "$script_dir"
+
+    cd ../..
+    flatpak_dir="build/flatpak"
+    mkdir -p "$flatpak_dir"
+    source ShellScripts/common/get_version.sh
+    run_script "$flatpak_dir"
+    local githash ver_full ver_quad ver_gitrev cpp_date app_date buildtime builder
+    source "$flatpak_dir/.meson_version"
+    cd "$flatpak_dir"
+
+    cp ../../installers/flatpak/space.oolite.Oolite.* ./
+    mkdir -p shared-modules/glu
+    if ! curl -o shared-modules/glu/glu-9.json -L https://github.com/flathub/shared-modules/raw/refs/heads/master/glu/glu-9.json; then
+        echo "❌ Flatpak download of glu shared module failed!" >&2
+        return 1
+    fi
+
+    local manifest="space.oolite.Oolite.yaml"
+    if ! sed -i "s|^[[:space:]]*- \./mk.sh.*|      - ./mk.sh flatpak-internal $build_type --ver-full=\"$ver_full\" --buildtime=\"$buildtime\" --github-repository=\"$github_repository\"|" "$manifest"; then
+        echo "❌ Replacement of ./mk.sh line in $manifest failed!" >&2
+        return 1
+    fi
+    tail -n 12 $manifest
+
+#    local lint_exceptions=$(mktemp /tmp/oolite-lint-XXXXXX.json)
+#    cat <<EOF > "$lint_exceptions"
+#{
+#  "space.oolite.Oolite": [
+#    "finish-args-has-dev-input"
+#  ]
+#}
+#EOF
+#    trap 'rm -f "$lint_exceptions"' RETURN EXIT
+#    if command -v flatpak-builder-lint >/dev/null 2>&1; then  # check manifest
+#        if ! flatpak-builder-lint manifest "$manifest" --exceptions --user-exceptions="$lint_exceptions"; then
+#            echo "❌ Flatpak manifest lint failed!" >&2
+#            cat "$manifest"
+#            echo "❌ Flatpak manifest lint failed!" >&2
+#            return 1
+#        fi
+#    else
+#        echo "Native linter not found. Falling back to Flatpak container..."
+#        if ! flatpak run --filesystem="$lint_exceptions" --command=flatpak-builder-lint org.flatpak.Builder manifest "$manifest" --exceptions --user-exceptions="$lint_exceptions"; then
+#            echo "❌ Flatpak manifest lint failed!" >&2
+#            return 1
+#        fi
+#    fi
+#    rm -f "$lint_exceptions"  # Clean up
+#    trap - RETURN EXIT
+
+    echo "Creating Flatpak..."
+    if ! flatpak remote-add \
+      --user \
+      --if-not-exists \
+      flathub https://flathub.org/repo/flathub.flatpakrepo; then
+        echo "❌ Flatpak adding Flathub remote failed!" >&2
+        return 1
+    fi
+
+    if ! sed -i "/- type: git/{
+        N;
+        /url:.*oolite\.git/{
+            N;N;
+            c\\
+      - type: dir\\
+        path: ../../
+        }
+    }" "$manifest"; then
+        echo "❌ Replacement of Oolite git repo source lines in $manifest failed!" >&2
+        return 1
+    fi
+    tail -n 12 $manifest
+
+    if ! flatpak-builder \
+      --user \
+      --force-clean \
+      --repo=repo \
+      --install-deps-from=flathub \
+      --disable-rofiles-fuse \
+      build-dir \
+      $manifest; then
+        echo "❌ Flatpak build failed!" >&2
+        return 1
+    fi
+
+    local suffix
+    if [[ "$build_type" != "deployment" ]]; then
+        suffix="_$build_type-$ver_full"
+    else
+        suffix="-$ver_full"
+    fi
+    local ARCH=$(uname -m)
+    local filename="space.oolite.Oolite${suffix}-${ARCH}.flatpak"
+    echo "Creating Flatpak $filename..."
+    if ! flatpak build-bundle \
+      repo \
+      "../$filename" \
+      space.oolite.Oolite; then
+        echo "❌ Flatpak bundle creation failed!" >&2
+        return 1
+    fi
+    local debugname="space.oolite.Oolite.Debug${suffix}-${ARCH}.flatpak"
+    if ! flatpak build-bundle \
+      --runtime \
+      repo \
+      "../$debugname" \
+      space.oolite.Oolite.Debug; then
+        echo "❌ Flatpak bundle creation failed!" >&2
+        return 1
+    fi
+
+    popd
+}
diff --git a/installers/flatpak/flatpak_build.sh b/installers/flatpak/flatpak_build.sh
deleted file mode 100755
index 503f5d8c1..000000000
--- a/installers/flatpak/flatpak_build.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-#!/bin/bash -x
-#
-# Prepares the app directory for the flatpak builder
-#
-
-echo "I am flatpak_build.sh $@"
-printenv | sort
-
-source ShellScripts/common/get_version.sh
-source ShellScripts/Linux/install_freedesktop_fn.sh
-
-export ADDITIONAL_CFLAGS="-DBUILD_DATE='\"$CPP_DATE\"'"
-export ADDITIONAL_OBJCFLAGS="-DBUILD_DATE='\"$CPP_DATE\"'"
-make release-deployment
-
-ABS_OOLITEDIR=$(realpath -m "build/meson_deployment/oolite.app")
-install_freedesktop $ABS_OOLITEDIR /app lib/debug/bin metainfo
-# Ensure the destination directory exists
-mkdir -p /app/lib/debug/source/oolite
-# Copy the src directory recursively
-cp -r src /app/lib/debug/source/oolite/ || {
-    echo "❌ $err_msg install oolite source code" >&2
-    return 1
-}
diff --git a/installers/flatpak/flatpak_postbuild_fn.sh b/installers/flatpak/flatpak_postbuild_fn.sh
new file mode 100755
index 000000000..a60f0a352
--- /dev/null
+++ b/installers/flatpak/flatpak_postbuild_fn.sh
@@ -0,0 +1,21 @@
+#!/bin/bash -x
+#
+# Prepares the app directory for the flatpak builder
+#
+
+flatpak_postbuild() {
+    local build_folder="$1"  # Build folder
+
+    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
+    pushd "$script_dir"
+    source ../FreeDesktop/install_freedesktop_fn.sh
+
+    cd ../../build/flatpak
+    install_freedesktop ver_full "../$build_folder" "/app" "lib/debug/bin" "metainfo"
+    mkdir -p /app/lib/debug/source/oolite  # Ensure the destination directory exists
+    cp -r ../../src /app/lib/debug/source/oolite/ || {  # Copy the src directory recursively
+        echo "❌ $err_msg install oolite source code" >&2
+        return 1
+    }
+    popd
+}
\ No newline at end of file
diff --git a/installers/flatpak/space.oolite.Oolite.yaml b/installers/flatpak/space.oolite.Oolite.yaml
index 33456d2ff..16398f6ae 100644
--- a/installers/flatpak/space.oolite.Oolite.yaml
+++ b/installers/flatpak/space.oolite.Oolite.yaml
@@ -111,13 +111,14 @@ modules:
     buildsystem: simple
     build-options:
       no-debuginfo: true
-      # CI builds add an env block here
     build-commands:
-      - source installers/flatpak/flatpak_build.sh
+      # Update --ver-full for FlatHub release. For CI and local builds, create_flatpak.sh replaces
+      # --ver-full and --github-repository values
+      - ./mk.sh flatpak deployment --ver-full="1.92.1" --buildtime="2026.03.19 07:13" --github-repository="OoliteProject/oolite"
     sources:
       # Update tag and commit for FlatHub release. For CI and local builds, create_flatpak.sh replaces git source with:
       # - type: dir
-      #   path: ../
+      #   path: ../../
       - type: git
         url: https://github.com/OoliteProject/oolite.git
         tag: "1.92.1.0"
diff --git a/installers/win32/OOlite.nsi b/installers/win32/OOlite.nsi
index 0f24d7858..9f0f0cd8c 100644
--- a/installers/win32/OOlite.nsi
+++ b/installers/win32/OOlite.nsi
@@ -1,5 +1,5 @@
 ; Include the NSIS logic library. Required for the code that handles 
-; adding of the changelog file in the non-snapshot distributions
+; adding of the changelog file in the non-dev distributions
 !include "LogicLib.nsh"
 
 ; Include the Sections library, required for being able to provide the 
@@ -14,10 +14,6 @@
 ; and it's too much work to try to dynamically edit this file
 !include /NONFATAL "OoliteVersions.nsh"
 
-!ifndef VER_GITREV
-!warning "No GIT Revision supplied"
-!define VER_GITREV 0
-!endif
 !ifndef VERSION
 !warning "No Version information supplied"
 !define VERSION 0.0.0.0
@@ -31,12 +27,12 @@
 !ifndef OUTDIR
 !define OUTDIR .
 !endif
-!ifndef SEMVER
-!define SEMVER ${VERSION}
+!ifndef VER_FULL
+!define VER_FULL ${VERSION}
 !endif
 
-!ifndef SNAPSHOT
-!ifndef DEPLOYMENT
+!ifndef DEV_RELEASE
+!ifndef DEPLOYMENT_RELEASE
 !define EXTVER "-test"  ; Official distribution with OXP developer tools
 !define ADDCHANGELOG 1	; Official distributions go with a changelog file
 !else
@@ -45,10 +41,10 @@
 !endif
 !else
 !define EXTVER "-dev"
-!define ADDCHANGELOG 0	; Snapshot distributions do not need changelog
+!define ADDCHANGELOG 0	; Dev distributions do not need changelog
 !endif
 
-!ifndef DEPLOYMENT
+!ifndef DEPLOYMENT_RELEASE
 !define DEBUGOXPINCLUDED 1
 !else
 !define DEBUGOXPINCLUDED 0
@@ -61,10 +57,10 @@ SetCompress auto
 SetCompressor LZMA
 SetCompressorDictSize 32
 SetDatablockOptimize on
-OutFile "${OUTDIR}\OoliteInstall-${SEMVER}-win${EXTVER}.exe"
+OutFile "${OUTDIR}\OoliteInstall-${VER_FULL}-win${EXTVER}.exe"
 BrandingText "(C) 2003-2026 Giles Williams, Jens Ayton and contributors"
 Name "Oolite"
-Caption "Oolite ${SEMVER} ${EXTVER} Setup"
+Caption "Oolite ${VER_FULL} ${EXTVER} Setup"
 SubCaption 0 " "
 SubCaption 1 " "
 SubCaption 2 " "
@@ -86,9 +82,9 @@ VIAddVersionKey "ProductName" "Oolite"
 VIAddVersionKey "FileDescription" "A space combat/trading game, inspired by Elite."
 VIAddVersionKey "LegalCopyright" "� 2003-2026 Giles Williams, Jens Ayton and contributors"
 VIAddVersionKey "FileVersion" "${VER}"
-VIAddVersionKey "ProductVersion" "${SEMVER}"
-!ifdef SNAPSHOT
-VIAddVersionKey "GIT Revision" "${VER_GITHASH}"
+VIAddVersionKey "ProductVersion" "${VER_FULL}"
+!ifdef DEV_RELEASE
+VIAddVersionKey "GIT Hash" "${VER_GITHASH}"
 !endif
 !ifdef BUILDTIME
 VIAddVersionKey "Build Time" "${BUILDTIME}"
@@ -104,7 +100,7 @@ VIProductVersion "${VER}"
 !define MUI_UNICON oolite.ico
 
 !insertmacro MUI_PAGE_DIRECTORY
-!ifndef DEPLOYMENT
+!ifndef DEPLOYMENT_RELEASE
 	!insertmacro MUI_PAGE_COMPONENTS
 !endif
 !insertmacro MUI_PAGE_INSTFILES
@@ -127,14 +123,14 @@ VIProductVersion "${VER}"
 
 !insertmacro MUI_LANGUAGE "English"
 
-!ifndef DEPLOYMENT
+!ifndef DEPLOYMENT_RELEASE
 ; Create the main game and Debug OXP sections
 Section "Oolite Game" ooGame
 SectionIn RO	; The game itself cannot be unselected
 SectionEnd
 
 Section "Basic-debug.OXP" ooDebugOXP
-; Do not use any of the Debug OXP files when we are building Deployment
+; Do not use any of the Debug OXP files when we are building deployment release
 SetOutPath $INSTDIR
 File /r "${DST}\AddOns"
 SectionEnd
@@ -200,7 +196,7 @@ uninst:
 done:
 FunctionEnd
 
-!ifndef DEPLOYMENT
+!ifndef DEPLOYMENT_RELEASE
 Function .onSelChange
 	${If} ${SectionIsSelected} ${ooDebugOXP}
 		!insertmacro SelectSection ${ooDebugOXP}
diff --git a/installers/win32/create_nsis.sh b/installers/win32/create_nsis_fn.sh
similarity index 52%
rename from installers/win32/create_nsis.sh
rename to installers/win32/create_nsis_fn.sh
index d4a74e8be..4fe950893 100644
--- a/installers/win32/create_nsis.sh
+++ b/installers/win32/create_nsis_fn.sh
@@ -1,24 +1,20 @@
 #!/bin/bash -x
 #
 # Creates the windows installer using NSIS.
-# First parameter can be set to build type, typically one of "test", "dev" or omitted for release builds.
-# Accepts two verion variables:
-#   VER_FULL - the full version number Oolite is getting built with
-#   VER_NSIS - the numberical version number (x.x.x.x) that the NSIS installer is built with
-#
-
-echo I am $0 $@
 
+create_nsis() {
+    local build_type="$1"  # Typically one of "deployment", "test", "dev"
+    local build_folder="$2"  # Build folder
 
-run_script() {
-    # First parameter is a suffix for the build type eg. test, dev
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir"
+    source ../../ShellScripts/common/parse_manifest_fn.sh
 
     mkdir -p ../../build/nsis
     cd ../../build/nsis
-    source ../../ShellScripts/common/get_version.sh
-
+    local oolite_dir="../$build_folder"
+    local ver_full ver_quad ver_githash buildtime app_date
+    parse_manifest ver_full ver_quad ver_githash buildtime app_date "$oolite_dir/Resources/manifest.plist"
     cp ../../installers/win32/* ./
 
     if ! curl -o OoliteReadMe.pdf -L https://oolite.readthedocs.io/en/latest/index.pdf; then
@@ -42,32 +38,24 @@ run_script() {
        return 1
     fi
 
-    local oolite_dir="../$1"
-    oolite_dir="${oolite_dir//\//\\}"
-
-    # Passing arguments cause problems with some versions of NSIS.
-    # Because of this, we generate them into a separate file and include them.
+    # Passing arguments can cause problems with NSIS so we generate them into a separate file and include them.
     echo "; Version Definitions for Oolite" > OoliteVersions.nsh
     echo "; NOTE - This file is auto-generated by the Makefile, any manual edits will be overwritten" >> OoliteVersions.nsh
-    echo "!define oolite_dir ${oolite_dir}" >> OoliteVersions.nsh
-    echo "!define VER_MAJ ${VER_MAJ}" >> OoliteVersions.nsh
-    echo "!define VER_MIN ${VER_MIN}" >> OoliteVersions.nsh
-    echo "!define VER_REV ${VER_REV}" >> OoliteVersions.nsh
-    echo "!define VER_GITREV ${VER_GITREV}" >> OoliteVersions.nsh
-    echo "!define VER_GITHASH ${VER_GITHASH}" >> OoliteVersions.nsh
-    echo "!define VERSION ${VER_NSIS}" >> OoliteVersions.nsh
-    echo "!define SEMVER ${VER_FULL}" >> OoliteVersions.nsh
-    echo "!define BUILDTIME \"${BUILDTIME}\"" >> OoliteVersions.nsh
+    echo "!define OOLITE_DIR ${oolite_dir//\//\\}" >> OoliteVersions.nsh
+    echo "!define VER_GITHASH ${ver_githash}" >> OoliteVersions.nsh
+    echo "!define VERSION ${ver_quad}" >> OoliteVersions.nsh
+    echo "!define VER_FULL ${ver_full}" >> OoliteVersions.nsh
+    echo "!define BUILDTIME \"${buildtime}\"" >> OoliteVersions.nsh
     echo "!define BUILDHOST_IS64BIT 1" >> OoliteVersions.nsh
 
-    if [[ "$2" == "dev" ]]; then
-        echo "!define SNAPSHOT 1" >> OoliteVersions.nsh
-    elif [[ "$2" != "test" ]]; then
-        echo "!define DEPLOYMENT 1" >> OoliteVersions.nsh
+    if [[ "$build_type" == "deployment" ]]; then
+        echo "!define DEPLOYMENT_RELEASE 1" >> OoliteVersions.nsh
+    elif [[ "$build_type" == "dev" ]]; then
+        echo "!define DEV_RELEASE 1" >> OoliteVersions.nsh
     fi
 
     local nsis
-    if [[ -n "$MINGW_PREFIX" ]]; then
+    if [[ -v MINGW_PREFIX ]]; then
         nsis=$MINGW_PREFIX/bin/makensis
     else
         nsis=/nsis/makensis.exe
@@ -78,13 +66,3 @@ run_script() {
     fi
     popd
 }
-
-run_script "$@"
-status=$?
-
-
-# Exit only if not sourced
-if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
-    exit $status
-fi
-
diff --git a/meson.build b/meson.build
index badc7b786..8397f071e 100644
--- a/meson.build
+++ b/meson.build
@@ -5,6 +5,7 @@ project(
     version: run_command(
         'bash',
         files('ShellScripts/common/get_version.sh'),
+        meson.project_build_root(),
         check: true,
     ).stdout().strip(),
     default_options: [
@@ -16,19 +17,22 @@ host_os = host_machine.system()
 c_family = ['c', 'cpp', 'objc']
 
 version_string = meson.project_version()
-add_project_arguments(
-    '-DOO_VERSION_FULL="@0@"'.format(version_string),
-    language: c_family,
-)
+cat_cmd = find_program('cat', required: true)
+version_file = meson.project_build_root() / '.meson_version'
+cat_result = run_command(cat_cmd, version_file, check: true)
+version_vars = {}
+file_contents = cat_result.stdout().strip()
 
-github_repository = get_option('github_repository')
-if github_repository == 'OoliteProject/oolite'
-    builder = 'OoliteProject'
-else
-    builder = 'unknown'
-endif
+foreach line : file_contents.split('\n')
+    parts = line.split('=')
+    key = parts[0].strip()
+    value = parts[1].strip('"\' ')
+    version_vars += { key : value }
+endforeach
 add_project_arguments(
-    '-DOO_BUILDER="@0@"'.format(builder),
+    '-DOO_VERSION_FULL="@0@"'.format(version_string),
+    '-DOO_BUILD_DATE="@0@"'.format(version_vars.get('app_date')),
+    '-DOO_BUILDER="@0@"'.format(version_vars.get('builder')),
     language: c_family,
 )
 
@@ -47,7 +51,7 @@ if get_option('no_shaders')
     add_project_arguments('-DNO_SHADERS=1', language: c_family)
 endif
 
-if get_option('deployment_release_configuration')
+if get_option('deployment_release')
     add_project_arguments(
         '-DNDEBUG',
         '-DOO_CHECK_GL_HEAVY=0',
@@ -81,10 +85,9 @@ else
     endif
 endif
 
-if get_option('snapshot_build')
+if get_option('dev_release')
     add_project_arguments(
-        '-DSNAPSHOT_BUILD',
-        '-DOOLITE_SNAPSHOT_VERSION="@0@"'.format(version_string),
+        '-DDEV_RELEASE',
         language: c_family,
     )
 endif
diff --git a/meson.options b/meson.options
index 7ff139544..138a83074 100644
--- a/meson.options
+++ b/meson.options
@@ -32,20 +32,14 @@ option('debug_graphviz', type: 'boolean', value: true,
        description: 'Enable AI state-machine graph visualization via GraphViz syntax output')
 
 # Release Variant Control
-option('deployment_release_configuration', type: 'boolean', value: false,
+option('deployment_release', type: 'boolean', value: false,
        description: 'Force a strict production deployment setup (overrides and disables most debugging instrumentation)')
 
-option('snapshot_build', type: 'boolean', value: false,
-       description: 'Mark the compilation as a development snapshot build')
+option('dev_release', type: 'boolean', value: false,
+       description: 'Mark the compilation as a development release')
 
 option('strip_bin', type: 'boolean', value: false, description: 'Enable stripping')
 
 # Windows Specific Customizations
 option('pdb', type: 'boolean', value: false,
        description: 'Windows Clang builds only: Generate native .pdb debug symbol files')
-
-# GitHub repository variable from CI if available
-option('github_repository', type: 'string', value: '',
-       description: 'GitHub repository variable from CI if available')
-
-
diff --git a/mk.sh b/mk.sh
new file mode 100755
index 000000000..80622f5c8
--- /dev/null
+++ b/mk.sh
@@ -0,0 +1,377 @@
+#!/bin/bash
+
+SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
+pushd "$SCRIPT_DIR" > /dev/null
+
+set -u -o pipefail  # Strict expansions
+
+cleanup_and_exit() {  # Error handling trap
+    local exit_code=$?
+
+    if [[ $exit_code -eq 0 ]]; then
+        exit_code=1  # force 0 exit code to 1 to indicate an error
+    fi
+    echo "❌ Oolite build failed on line $1 with exit code $exit_code!" >&2
+    popd > /dev/null 2>&1 || true  # Always pop the directory stack before exiting
+    if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then  # Exit only if not sourced
+        exit "$exit_code"
+    fi
+}
+trap 'cleanup_and_exit ${LINENO}' ERR  # Trap any command errors (ERR) passing ${LINENO} to know where it failed
+
+output_meson_log() {
+    meson_log="$1/meson-logs/meson-log.txt"
+    if [[ -f "$meson_log" ]]; then
+        echo -e "\n=== MESON LOG START ===" >&2
+        cat "$meson_log" >&2
+        echo -e "=== MESON LOG END ===\n" >&2
+    fi
+}
+
+# --- Feature Flags & Options ---
+NATIVE_FILE=""
+VER_FULL=""
+BUILDTIME=""
+GITHUB_REPOSITORY=""
+CLEAN_BUILD=false
+SETUP_FLAGS=() # Array to cleanly store additional meson setup arguments
+COMPILE_FLAGS=() # Array to cleanly store additional meson compile arguments
+CONFIGURE_FLAGS=() # Array to cleanly store additional meson configure arguments
+INSTALL_FLAGS=() # Array to cleanly store additional meson install arguments
+
+clean() {
+    echo "--> Cleaning target build directory: $1"
+    rm -rf "$1"
+}
+
+meson_setup() {
+    local build_dir="build/meson_$1"
+    echo "--> Running Meson setup for: $1"
+    local meson_opts=("${@:2}")
+    if [[ -n "${VER_FULL:-}" ]]; then
+        export VER_FULL
+    fi
+    if [[ -n "${BUILDTIME:-}" ]]; then
+        export BUILDTIME
+    fi
+    if [[ -n "${GITHUB_REPOSITORY:-}" ]]; then
+        export GITHUB_REPOSITORY
+    fi
+    if [[ -d "$build_dir" ]] && [[ -f "$build_dir/build.ninja" ]]; then
+        echo "🔄 Directory exists, attempting to reconfigure..."
+        if ! meson setup "$build_dir" "${meson_opts[@]}" ${SETUP_FLAGS[@]+"${SETUP_FLAGS[@]}"} --native-file "${NATIVE_FILE}" --reconfigure; then
+            echo "❌ Meson reconfiguration failed!" >&2
+            output_meson_log "$build_dir"
+            exit 1
+        fi
+    else
+        echo "🏗️ Creating new build configuration..."
+        if ! meson setup "$build_dir" "${meson_opts[@]}" ${SETUP_FLAGS[@]+"${SETUP_FLAGS[@]}"} --native-file "${NATIVE_FILE}"; then
+            echo "❌ Meson initial setup failed!" >&2
+            output_meson_log "$build_dir"
+            exit 1
+        fi
+    fi
+}
+
+meson_compile() {
+    local build_dir="build/meson_$1"
+    echo "--> Running Meson build for: $1"
+    if ! meson compile -C "$build_dir" ${COMPILE_FLAGS[@]+"${COMPILE_FLAGS[@]}"}; then
+        echo "❌ Meson compile failed!" >&2
+        output_meson_log "$build_dir"
+        exit 1
+    fi
+}
+
+meson_configure() {
+    local build_dir="build/meson_$1"
+    echo "--> Running Meson configure for: $1"
+    local meson_opts=("${@:2}")
+    if ! meson configure "$build_dir" "${meson_opts[@]}" ${CONFIGURE_FLAGS[@]+"${CONFIGURE_FLAGS[@]}"}; then
+        echo "❌ Meson configure failed!" >&2
+        output_meson_log "$build_dir"
+        exit 1
+    fi
+}
+
+meson_install() {
+    local build_dir="build/meson_$1"
+    echo "--> Running Meson install for: $1"
+    if ! meson install -C "$build_dir" ${INSTALL_FLAGS[@]+"${INSTALL_FLAGS[@]}"}; then
+        echo "❌ Meson install failed!" >&2
+        output_meson_log "$build_dir"
+        exit 1
+    fi
+}
+
+show_help() {  # Script Help Menu
+    echo "Usage: $0 [options] <action> <build_type>"
+    echo "       $0 [options] <global_action>"
+    echo ""
+    echo "Options:"
+    echo -e "  \033[36m--setup-flags=\"...\"\033[0m          Pass additional arguments directly to 'meson setup'"
+    echo -e "  \033[36m--compile-flags=\"...\"\033[0m        Pass additional arguments directly to 'meson compile'"
+    echo -e "  \033[36m--configure-flags=\"...\"\033[0m      Pass additional arguments directly to 'meson configure'"
+    echo -e "  \033[36m--install-flags=\"...\"\033[0m        Pass additional arguments directly to 'meson install'"
+    echo -e "  \033[36m--native-file=\"...\"\033[0m          Specify native file (defaults to clang.ini)"
+    echo -e "  \033[36m--ver-full=\"...\"\033[0m             Specify full version string"
+    echo -e "  \033[36m--buildtime=\"...\"\033[0m            Specify build time"
+    echo -e "  \033[36m--github-repository=\"...\"\033[0m    Specify target GitHub repository"
+    echo ""
+    echo "Build Type Actions (Requires build_type as second parameter):"
+    echo -e "  \033[36msetup <build_type>\033[0m              Setup a release build directory"
+    echo -e "  \033[36mcompile <build_type>\033[0m            Compile a build directory"
+    echo -e "  \033[36mbuild <build_type>\033[0m              Setup and compile a build directory"
+    echo -e "  \033[36mconfigure <build_type>\033[0m          Modify build options of an existing build directory"
+    echo -e "  \033[36minstall <build_type>\033[0m            Install an existing build directory"
+    echo -e "  \033[36mtest <build_type>\033[0m               Run test suites (deployment build_type excluded)"
+    echo -e "  \033[36mclean <build_type>\033[0m              Clean a specific build_type's directory"
+    echo -e "  \033[36mflatpak-internal <build_type>\033[0m   Build flatpak dependencies internally"
+    echo -e "  \033[36mpkg-flatpak <build_type>\033[0m        Package a Flatpak application"
+    echo -e "  \033[36mpkg-appimage <build_type>\033[0m       Package a Linux AppImage installer"
+    echo -e "  \033[36mpkg-win <build_type>\033[0m            Package a Windows NSIS installer"
+    echo ""
+    echo "Global Actions:"
+    echo -e "  \033[36mclean-all\033[0m                    Remove generated artifacts for all builds"
+    echo -e "  \033[36mhelp\033[0m                         Show this breakdown menu"
+    echo ""
+    echo "Build Types:"
+    echo -e "  \033[32mdeployment, test, dev, debug\033[0m"
+}
+
+validate_build_type() {
+    local build_type="$1"
+    if [[ "$build_type" != "deployment" && "$build_type" != "test" && "$build_type" != "dev" && "$build_type" != "debug" ]]; then
+        echo "❌ Invalid build_type '$build_type'. Expected: deployment, test, dev, or debug." >&2
+        exit 1
+    fi
+}
+
+execute_target() {  # Target Execution Logic
+    local action="$1"
+    local build_type="${2:-}"
+
+case "$action" in
+        setup)
+            validate_build_type "$build_type"
+            if [[ "$build_type" == "deployment" ]]; then
+                # Arguments passed individually (acts like an array)
+                meson_setup "deployment" "-Ddeployment_release=true" "-Ddebug=false" "-Dstrip_bin=true" "-Db_lto=true"
+            elif [[ "$build_type" == "test" ]]; then
+                meson_setup "test" "-Ddebug=false" "-Dstrip_bin=true" "-Db_lto=true"
+            elif [[ "$build_type" == "dev" ]]; then
+                meson_setup "dev" "-Ddev_release=true" "-Ddebug=false" "-Dstrip_bin=false"
+            elif [[ "$build_type" == "debug" ]]; then
+                meson_setup "debug" "-Ddebug=true" "-Dstrip_bin=false"
+            fi
+            ;;
+        compile)
+            validate_build_type "$build_type"
+            meson_compile "$build_type"
+            ;;
+        build)
+            validate_build_type "$build_type"
+            execute_target "setup" "$build_type"
+            execute_target "compile" "$build_type"
+            ;;
+        configure)
+            validate_build_type "$build_type"
+            meson_configure "$build_type"
+            ;;
+        install)
+            validate_build_type "$build_type"
+            meson_install "$build_type"
+            ;;
+        test)
+            validate_build_type "$build_type"
+            if [[ "$build_type" == "deployment" ]]; then
+                echo "❌ Cannot test deployment as not set up for debug console!" >&2
+                exit 1
+            fi
+            source tests/run_test_fn.sh && run_test "$build_type"
+            ;;
+        clean)
+            if [[ "$build_type" == "appimage" ]]; then
+                clean "build/appimage"
+            elif [[ "$build_type" == "flatpak" ]]; then
+                clean "build/flatpak"
+            else
+                validate_build_type "$build_type"
+                clean "build/meson_$build_type"
+            fi
+            ;;
+        flatpak-internal)
+            validate_build_type "$build_type"
+            execute_target "build" "$build_type"
+            if ! meson_configure "$build_type" "--prefix=/app"; then
+                echo "❌ Flatpak meson configure with prefix /app failed!" >&2
+                exit 1
+            fi
+            if ! meson_install "$build_type"; then
+                echo "❌ Flatpak meson install failed!" >&2
+                exit 1
+            fi
+            if ! source installers/flatpak/flatpak_postbuild_fn.sh; then
+                echo "❌ Failed to source flatpak_postbuild_fn.sh!" >&2
+                exit 1
+            fi
+            if ! flatpak_postbuild "meson_${build_type}/oolite.app"; then
+                echo "❌ Flatpak post build failed!" >&2
+                exit 1
+            fi
+            ;;
+        pkg-flatpak)
+            validate_build_type "$build_type"
+            if ! source installers/flatpak/create_flatpak_fn.sh; then
+                echo "❌ Failed to source create_flatpak_fn.sh!" >&2
+                exit 1
+            fi
+            if ! create_flatpak "$build_type" "$GITHUB_REPOSITORY"; then
+                echo "❌ Flatpak generation failed!" >&2
+                exit 1
+            fi
+            ;;
+        pkg-appimage)
+            validate_build_type "$build_type"
+            local appdir=$(realpath -m "build/appimage/oolite.AppDir")
+            if ! meson_configure "$build_type" "--prefix=$appdir"; then
+                echo "❌ AppImage meson configure with prefix /app failed!" >&2
+                exit 1
+            fi
+            if ! meson_install "$build_type"; then
+                echo "❌ AppImage meson install failed!" >&2
+                exit 1
+            fi
+            if ! source installers/appimage/create_appimage_fn.sh; then
+                echo "❌ Failed to source create_appimage_fn.sh!" >&2
+                exit 1
+            fi
+            if ! create_appimage "$build_type" "meson_${build_type}/oolite.app"; then
+                echo "❌ AppImage generation failed!" >&2
+                exit 1
+            fi
+            ;;
+        pkg-win)
+            validate_build_type "$build_type"
+            if ! source installers/win32/create_nsis_fn.sh; then
+                echo "❌ Failed to source create_nsis_fn.sh!" >&2
+                exit 1
+            fi
+            if ! create_nsis "$build_type" "meson_${build_type}/oolite.app"; then
+                echo "❌ NSIS generation failed!" >&2
+                exit 1
+            fi
+            ;;
+        *)
+            echo "❌ Fatal structural error handling action '$action'" >&2
+            exit 1
+            ;;
+    esac
+}
+
+ACTION=""
+BUILD_TYPE=""
+
+# --- Flexible Argument Parser (Allows flags and positionals anywhere) ---
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --setup-flags=*)
+            read -r -a flags_array <<< "${1#*=}"
+            SETUP_FLAGS+=("${flags_array[@]}")
+            shift
+            ;;
+        --compile-flags=*)
+            read -r -a flags_array <<< "${1#*=}"
+            COMPILE_FLAGS+=("${flags_array[@]}")
+            shift
+            ;;
+        --configure-flags=*)
+            read -r -a flags_array <<< "${1#*=}"
+            CONFIGURE_FLAGS+=("${flags_array[@]}")
+            shift
+            ;;
+        --install-flags=*)
+            read -r -a flags_array <<< "${1#*=}"
+            INSTALL_FLAGS+=("${flags_array[@]}")
+            shift
+            ;;
+        --native-file=*)
+            NATIVE_FILE="${1#*=}"
+            shift
+            ;;
+        --ver-full=*)
+            VER_FULL="${1#*=}"
+            shift
+            ;;
+        --buildtime=*)
+            BUILDTIME="${1#*=}"
+            shift
+            ;;
+        --github-repository=*)
+            GITHUB_REPOSITORY="${1#*=}"
+            shift
+            ;;
+        help|--help|-h)
+            show_help
+            exit 0
+            ;;
+        -*)
+            echo "❌ Unknown option '$1'" >&2
+            show_help
+            exit 1
+            ;;
+        *)
+            # Process sequential text items dynamically
+            if [[ -z "$ACTION" ]]; then
+                ACTION="$1"
+            elif [[ -z "$BUILD_TYPE" ]]; then
+                BUILD_TYPE="$1"
+            else
+                echo "❌ Unexpected extra argument '$1'." >&2
+                show_help
+                exit 1
+            fi
+            shift
+            ;;
+    esac
+done
+
+if [[ -z "$ACTION" ]]; then
+    show_help  # Fallback to help menu if no action was provided
+    exit 1
+fi
+
+# Intercept global action 'clean-all' before validating build_type requirements
+if [[ "$ACTION" == "clean-all" ]]; then
+    echo "--> Cleaning all build artifacts..."
+    rm -rf build/meson_*
+    rm -rf build/flatpak
+    rm -rf build/appimage
+    trap - ERR
+    popd > /dev/null
+    echo "✅ Oolite task 'clean-all' completed successfully"
+    exit 0
+fi
+
+# Everything past this point strictly requires a build_type parameter
+if [[ -z "$BUILD_TYPE" ]]; then
+    echo "❌ Error: Action '$ACTION' requires a target build_type parameter." >&2
+    show_help
+    exit 1
+fi
+
+if [[ -z "$NATIVE_FILE" ]]; then
+    NATIVE_FILE="clang.ini"  # Apply default if it wasn't passed as an option
+fi
+
+execute_target "$ACTION" "$BUILD_TYPE"
+
+trap - ERR  # Successful Exit
+popd > /dev/null
+
+echo "✅ Oolite task '$ACTION $BUILD_TYPE' completed successfully"
+
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    exit 0
+fi
\ No newline at end of file
diff --git a/src/Core/OOLogHeader.m b/src/Core/OOLogHeader.m
index c2522d6b0..1e19beb86 100644
--- a/src/Core/OOLogHeader.m
+++ b/src/Core/OOLogHeader.m
@@ -161,7 +161,7 @@ void OOPrintLogHeader(void)
 	#endif
 	
 	NSString *versionString = nil;
-	#if (defined (SNAPSHOT_BUILD))
+	#if (defined (DEV_RELEASE))
 		versionString = @"development version " @OO_VERSION_FULL;
 	#else
 		versionString = @"version " @OO_VERSION_FULL;
diff --git a/src/Core/Universe.m b/src/Core/Universe.m
index 68138c75e..bd8ecc0ce 100644
--- a/src/Core/Universe.m
+++ b/src/Core/Universe.m
@@ -5243,7 +5243,7 @@ - (void) drawUniverse
 			// should come after the HUD to avoid it being overlapped by it
 			[self drawMessage];
 			
-#if (defined (SNAPSHOT_BUILD))
+#if (defined (DEV_RELEASE))
 			[self drawWatermarkString:@"Development version " @OO_VERSION_FULL];
 #endif
 			
diff --git a/src/SDL/MyOpenGLView.m b/src/SDL/MyOpenGLView.m
index 814d37fb3..0b4f3e8d2 100644
--- a/src/SDL/MyOpenGLView.m
+++ b/src/SDL/MyOpenGLView.m
@@ -145,11 +145,7 @@ - (NSMutableDictionary *) getNativeSize
 
 - (NSString*) getWindowCaption
 {
-#ifdef BUILD_DATE
-	NSString *caption = [NSString stringWithFormat:@"Oolite v%@ by %@ - %s", @OO_VERSION_FULL, @OO_BUILDER, BUILD_DATE];
-#else
-	NSString *caption = [NSString stringWithFormat:@"Oolite v%@ by %@ - %s", @OO_VERSION_FULL, @OO_BUILDER, __DATE__];
-#endif
+	NSString *caption = [NSString stringWithFormat:@"Oolite v%@ by %@ - %@", @OO_VERSION_FULL, @OO_BUILDER, @OO_BUILD_DATE];
 	return [[caption retain] autorelease];
 }
 
diff --git a/src/meson.build b/src/meson.build
index 314faa0ed..6c3dd2fb3 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -35,42 +35,44 @@ oolite_bin = executable(
     install: false,
 )
 
+bash_prog = find_program('bash')
 prog_dir = meson.global_build_root() / appname + '.app'
 stamp_file = '.oolite_bundle.stamp'
-install_env_args = [
-    'ORIGPROGPATH=' + meson.current_build_dir() / appname,
-    'PROGDIR=' + prog_dir,
-    'HOST_OS=' + host_os,
-    'DEBUG=' + (get_option('debug') ? 'yes' : 'no'),
-    'DEPLOYMENT_RELEASE_CONFIGURATION=' + (
-        get_option('deployment_release_configuration') ? 'yes' : 'no'
-    ),
-    'ESPEAK=' + (get_option('espeak') ? 'yes' : 'no'),
-    'STRIP_BIN=' + (get_option('strip_bin') ? 'yes' : 'no'),
-    'VER_FULL=' + version_string,
-    'GNUSTEP_FOLDER=' + gnustep_folder,
-    'STAMP_FILE=' + stamp_file,
+post_build_args = [
+    meson.current_build_dir() / appname,
+    prog_dir,
+    host_os,
+    get_option('debug') ? 'yes' : 'no',
+    get_option('deployment_release') ? 'yes' : 'no',
+    get_option('espeak') ? 'yes' : 'no',
+    get_option('strip_bin') ? 'yes' : 'no',
+    version_string,
+    version_vars.get('ver_quad'),
+    version_vars.get('ver_githash'),
+    version_vars.get('buildtime'),
+    gnustep_folder,
+    stamp_file,
 ]
-post_build_script = find_program('../ShellScripts/common/post_build.sh')
+post_build_script = files('../ShellScripts/common/post_build.sh')
+generate_manifest_script = files('../ShellScripts/common/generate_manifest_fn.sh')
 oolite_app_bundle = custom_target('post_build',
                                   input: oolite_bin,
                                   output: stamp_file,
-                                  depend_files: [post_build_script.full_path()],
                                   command: [
-                                      'env',
-                                      install_env_args,
-                                      post_build_script.full_path(),
+                                      bash_prog,
+                                      post_build_script,
+                                      post_build_args,
                                   ],
+                                  depend_files: [generate_manifest_script],
                                   build_by_default: true,
                                   install: false,
 )
-install_env_args = [
-    'STAGEPROGPATH=' + prog_dir / appname,
-    'BINDIR=' + get_option('bindir'),
-    'DATADIR=' + get_option('datadir'),
-    'HOST_OS=' + host_os,
-    'DEPLOYMENT_RELEASE_CONFIGURATION=' + (
-    get_option('deployment_release_configuration') ? 'yes' : 'no'),
+install_args = [
+    prog_dir / appname,
+    get_option('bindir'),
+    get_option('datadir'),
+    host_os,
+    get_option('deployment_release') ? 'yes' : 'no',
 ]
-install_script = find_program('../ShellScripts/common/install.sh')
-meson.add_install_script('env', install_env_args, install_script.full_path())
\ No newline at end of file
+install_script = files('../ShellScripts/common/install.sh')
+meson.add_install_script(bash_prog, install_script, install_args)
diff --git a/tests/run_test.sh b/tests/run_test_fn.sh
similarity index 84%
rename from tests/run_test.sh
rename to tests/run_test_fn.sh
index f345ab359..5061c75e5 100755
--- a/tests/run_test.sh
+++ b/tests/run_test_fn.sh
@@ -9,7 +9,7 @@ output_log() {
     fi
 }
 
-run_script() {
+run_test() {
     if python3 --version >/dev/null 2>&1; then
         local PYTHON_CMD="python3"
     elif python --version >/dev/null 2>&1; then
@@ -22,10 +22,10 @@ run_script() {
     local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
     pushd "$script_dir"
 
-    local BUILD_TYPE="${1:-snapshot}"
+    local BUILD_TYPE="${1:-dev}"
     local TARGET_DIR=$(readlink -f "../build/meson_${BUILD_TYPE}/oolite.app")
-    if [[ -n "$MSYSTEM" ]]; then
-        local MESA_DLL="${MSYSTEM_PREFIX}/bin/opengl32.dll"
+    if [[ -v MINGW_PREFIX ]]; then
+        local MESA_DLL="${MINGW_PREFIX}/bin/opengl32.dll"
         if [[ -f "$MESA_DLL" ]]; then
             echo "📦 Copying $MSYSTEM Mesa driver at $MESA_DLL"
             cp "$MESA_DLL" "$TARGET_DIR/"
@@ -50,12 +50,3 @@ run_script() {
     echo "✅ Oolite test completed successfully"
     popd
 }
-
-run_script "$@"
-status=$?
-
-# Exit only if not sourced
-if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
-    exit $status
-fi
-