diff --git a/Dockerfile b/Dockerfile
index 2673c41..be63800 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -6,26 +6,10 @@ ARG TARGETOS
 ARG TARGETARCH
 ARG TARGETVARIANT
 
-RUN apt-get update && \
-  DEBIAN_FRONTEND=noninteractive apt-get install -y \
-    curl \
-    openssl \
-    unzip \
-    jq \
-    && apt-get clean \
-    && rm -rf /var/lib/apt/lists/*
-
-# Install box64 on arm
-RUN if [ "$TARGETARCH" = "arm64" ] ; then \
-    apt-get update && \
-    DEBIAN_FRONTEND=noninteractive apt-get install -y debian-keyring && \
-    curl -L https://ryanfortner.github.io/box64-debs/box64.list -o /etc/apt/sources.list.d/box64.list && \
-    curl -L https://ryanfortner.github.io/box64-debs/KEY.gpg | gpg --dearmor | tee /etc/apt/trusted.gpg.d/box64-debs-archive-keyring.gpg && \
-    apt-get update && \
-    DEBIAN_FRONTEND=noninteractive apt-get install -y box64-arm64 \
-        && apt-get clean \
-        && rm -rf /var/lib/apt/lists/* ;\
-    fi
+RUN --mount=target=/build,source=build /build/install-packages
+
+ARG BOX64_PACKAGE=box64
+RUN --mount=target=/build,source=build BOX64_PACKAGE=$BOX64_PACKAGE /build/setup-arm64
 
 EXPOSE 19132/udp
 
diff --git a/README.md b/README.md
index d19aa0a..e89b857 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,7 @@ The following environment variables will set the equivalent property in `server.
 - `SERVER_PORT`
 - `SERVER_PORT_V6`
 - `GAMEMODE`
+- `FORCE_GAMEMODE`
 - `DIFFICULTY`
 - `LEVEL_TYPE`
 - `ALLOW_CHEATS`
diff --git a/build/install-packages b/build/install-packages
new file mode 100755
index 0000000..a86cd3e
--- /dev/null
+++ b/build/install-packages
@@ -0,0 +1,15 @@
+#!/bin/sh
+
+set -eu
+
+apt-get update
+
+DEBIAN_FRONTEND=noninteractive apt-get install -y \
+    curl \
+    openssl \
+    unzip \
+    jq
+
+apt-get clean
+
+rm -rf /var/lib/apt/lists/*
\ No newline at end of file
diff --git a/build/setup-arm64 b/build/setup-arm64
new file mode 100755
index 0000000..58caf69
--- /dev/null
+++ b/build/setup-arm64
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+set -eu
+
+if [ "$TARGETARCH" = "arm64" ] ; then
+  apt-get update
+  DEBIAN_FRONTEND=noninteractive apt-get install -y debian-keyring
+
+  curl -L https://ryanfortner.github.io/box64-debs/box64.list -o /etc/apt/sources.list.d/box64.list
+  curl -L https://ryanfortner.github.io/box64-debs/KEY.gpg | gpg --dearmor | tee /etc/apt/trusted.gpg.d/box64-debs-archive-keyring.gpg
+
+  apt-get update
+  DEBIAN_FRONTEND=noninteractive apt-get install -y "$BOX64_PACKAGE"
+
+  apt-get clean
+  rm -rf /var/lib/apt/lists/*
+fi
\ No newline at end of file
diff --git a/property-definitions.json b/property-definitions.json
index 2f14cc6..cfb34d5 100644
--- a/property-definitions.json
+++ b/property-definitions.json
@@ -17,6 +17,10 @@
       "2": "adventure"
     }
   },
+  "force-gamemode": {
+    "env": "FORCE_GAMEMODE",
+    "allowed": ["true","false"]
+  },
   "difficulty": {
     "env": "DIFFICULTY",
     "allowed": ["easy","peaceful","normal","hard"],