diff --git a/Dockerfile b/Dockerfile
index a60d4bc71..38e54132a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,9 +1,11 @@
+#syntax=docker/dockerfile:1.2
+
 #
 # base installs required dependencies and runs go mod download to cache dependencies
 #
 # Pinned to alpine3.18 until https://github.com/mattn/go-sqlite3/issues/1164 is solved
 ARG BUILDPLATFORM=${BUILDPLATFORM}
-FROM --platform=$BUILDPLATFORM docker.io/golang:1.21-alpine AS base
+FROM --platform=$BUILDPLATFORM docker.io/golang:1.21-alpine3.18 AS base
 RUN apk --update --no-cache add bash build-base curl git
 
 #
@@ -13,8 +15,9 @@ FROM --platform=$BUILDPLATFORM base AS build
 WORKDIR /src
 ARG TARGETOS
 ARG TARGETARCH
+ARG FLAGS
 
-# Mount volumes using the -v flag instead of --mount to avoid requiring BuildKit which is not easily supported using cloudbuild.
+# Not mounting volumes using the --mount flag to avoid requiring BuildKit which is not easily supported using cloudbuild.
 COPY . .
 RUN mkdir -p /root/.cache/go-build && \
     mkdir -p /go/pkg/mod
@@ -23,10 +26,10 @@ VOLUME /go/pkg/mod
 
 # Run the build command in multiple RUN commands
 RUN USERARCH=`go env GOARCH`
-ENV GOARCH="$TARGETARCH"
-ENV GOOS="linux"
+RUN GOARCH="$TARGETARCH"
+RUN GOOS="linux"
 RUN CGO_ENABLED=$([ "$TARGETARCH" = "$USERARCH" ] && echo "1" || echo "0")
-RUN go build -v -trimpath -o /out/ ./cmd/...
+RUN go build -v -ldflags="${FLAGS}" -trimpath -o /out/ ./cmd/...
 
 #
 # Builds the Dendrite image containing all required binaries
@@ -37,8 +40,8 @@ LABEL org.opencontainers.image.title="Dendrite"
 LABEL org.opencontainers.image.description="Next-generation Matrix homeserver written in Go"
 LABEL org.opencontainers.image.source="https://github.com/matrix-org/dendrite"
 LABEL org.opencontainers.image.licenses="Apache-2.0"
-LABEL org.opencontainers.image.vendor="The Matrix.org Foundation C.I.C."
 LABEL org.opencontainers.image.documentation="https://matrix-org.github.io/dendrite/"
+LABEL org.opencontainers.image.vendor="The Matrix.org Foundation C.I.C."
 
 COPY --from=build /out/create-account /usr/bin/create-account
 COPY --from=build /out/generate-config /usr/bin/generate-config