diff --git a/Dockerfile b/Dockerfile
index 7d338b1..c5b0a38 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,40 +1,50 @@
 # syntax=docker/dockerfile:1
 
-# ============================================================
-# Stage 1: compile OpenSSL 1.1.1, jemalloc, Ruby
-# ============================================================
-FROM debian:bookworm-slim AS builder
+FROM debian:stable-20260610-slim@sha256:34363c20bd149e41365fc77b086da067ed13ab2dff4cd0612788e12e6d52c44c
 
 ARG OPENSSL_VERSION=1.1.1w
 ARG JEMALLOC_VERSION=5.3.1
 ARG RUBY_VERSION=2.6.10
 
+LABEL \
+    org.opencontainers.image.title="ruby2.6-jemalloc" \
+    org.opencontainers.image.description="Ruby ${RUBY_VERSION} image with jemalloc ${JEMALLOC_VERSION}" \
+    org.opencontainers.image.source="https://github.com/UMNLibraries/ruby2.6-jemalloc-docker"
+
 ENV DEBIAN_FRONTEND=noninteractive
 
-RUN <<'EOF'
+RUN <<__install__
 set -eux
 # Step: install builder dependencies
 apt-get update
+apt-get -y upgrade
 apt-get install -y --no-install-recommends \
     autoconf \
     bison \
     build-essential \
     bzip2 \
     ca-certificates \
+    libdb-dev \
     libffi-dev \
+    libffi8 \
     libgdbm-dev \
+    libgdbm6 \
     libncurses5-dev \
+    libncurses6 \
     libreadline-dev \
+    libreadline8 \
+    libyaml-0-2 \
     libyaml-dev \
     pkg-config \
     wget \
+    zlib1g \
     zlib1g-dev
 rm -rf /var/lib/apt/lists/*
-EOF
+__install__
 
 # Build OpenSSL 1.1.1 (required by Ruby 2.6; Debian ships OpenSSL 3 which is incompatible)
 WORKDIR /tmp/build
-RUN <<EOF
+RUN <<__openssl__
 set -eux
 # Step: download OpenSSL source
 wget -q "https://www.openssl.org/source/openssl-${OPENSSL_VERSION}.tar.gz"
@@ -44,14 +54,15 @@ cd "openssl-${OPENSSL_VERSION}"
 # Step: configure and build OpenSSL
 ./config --prefix=/opt/openssl --openssldir=/opt/openssl shared zlib
 make -j"$(nproc)"
+make test
 make install_sw
 
 # Step: clean OpenSSL build artifacts
 rm -rf /tmp/build/openssl-*
-EOF
+__openssl__
 
 # Build jemalloc
-RUN <<EOF
+RUN <<__jemalloc__
 set -eux
 # Step: download jemalloc source
 wget -q "https://github.com/jemalloc/jemalloc/releases/download/${JEMALLOC_VERSION}/jemalloc-${JEMALLOC_VERSION}.tar.bz2"
@@ -61,22 +72,21 @@ cd "jemalloc-${JEMALLOC_VERSION}"
 # Step: configure and build jemalloc
 ./configure --prefix=/usr/local
 make -j"$(nproc)"
+make test
 make install
 
 # Step: clean jemalloc build artifacts
 rm -rf /tmp/build/jemalloc-*
-EOF
+__jemalloc__
 
 # Build Ruby 2.6.x with jemalloc and OpenSSL 1.1.1
 ENV LD_LIBRARY_PATH=/opt/openssl/lib:/usr/local/lib
-RUN <<EOF
+RUN <<__ruby__
 set -eux
-# Step: download Ruby source
 wget -q "https://cache.ruby-lang.org/pub/ruby/2.6/ruby-${RUBY_VERSION}.tar.gz"
 tar xzf "ruby-${RUBY_VERSION}.tar.gz"
 cd "ruby-${RUBY_VERSION}"
 
-# Step: configure and build Ruby
 ./configure \
     --prefix=/usr/local \
     --with-openssl-dir=/opt/openssl \
@@ -86,63 +96,12 @@ cd "ruby-${RUBY_VERSION}"
     --disable-install-rdoc \
     CFLAGS="-O2 -fno-omit-frame-pointer -Wno-error=implicit-function-declaration"
 make -j"$(nproc)"
+make test
 make install
 
-# Step: clean Ruby build artifacts
 rm -rf /tmp/build/ruby-*
-EOF
-
-# ============================================================
-# Stage 2: Final – small runtime image with debian base
-# ============================================================
-FROM debian:bookworm-slim
-
-ARG RUBY_VERSION=2.6.10
-
-LABEL org.opencontainers.image.title="ruby2.6-jemalloc-docker" \
-    org.opencontainers.image.description="Ruby 2.6 image with jemalloc 5.3.1" \
-    org.opencontainers.image.version="${RUBY_VERSION}" \
-    org.opencontainers.image.source="https://github.com/UMNLibraries/ruby2.6-jemalloc-docker"
-
-ENV RUBY_VERSION=${RUBY_VERSION}
 
-# Copy compiled Ruby, OpenSSL, and CA certificates from builder.
-COPY --from=builder /usr/local /usr/local
-COPY --from=builder /opt/openssl /opt/openssl
-COPY --from=builder /etc/ssl/certs /etc/ssl/certs
-
-# Install runtime library dependencies and register compiled library paths.
-# Remove unnecessary build artifacts (headers, static libs, pkgconfig) to minimize image size.
-RUN <<'EOF'
-set -eux
-
-# Step: install runtime dependencies required by Ruby, OpenSSL, jemalloc
-apt-get update
-apt-get install -y --no-install-recommends \
-    libffi8 \
-    libgdbm6 \
-    libncurses6 \
-    libreadline8 \
-    libyaml-0-2 \
-    zlib1g \
-    ca-certificates
-
-# Step: remove build artifacts from copied Ruby and OpenSSL
-rm -rf /usr/local/include \
-       /usr/local/lib/pkgconfig \
-       /usr/local/lib/*.a \
-       /usr/local/share/doc \
-       /usr/local/share/man \
-       /opt/openssl/include \
-       /opt/openssl/lib/pkgconfig \
-       /opt/openssl/lib/*.a
-
-# Step: register compiled library paths for Ruby and OpenSSL at runtime
 ldconfig /opt/openssl/lib /usr/local/lib
-
-# Step: clean apt caches and temporary files
-rm -rf /var/lib/apt/lists/* /var/tmp/* /tmp/*
-
-EOF
+__ruby__
 
 CMD ["irb"]
diff --git a/Makefile b/Makefile
index 3c3dff8..047a7e1 100644
--- a/Makefile
+++ b/Makefile
@@ -38,10 +38,15 @@ lint:
 	pre-commit run --all-file
 
 build:
-	docker build --no-cache --progress=plain --platform "$(MULTIARCH_PLATFORMS)" --tag $(REGISTRY):latest .
+	docker build --progress=plain --platform "$(MULTIARCH_PLATFORMS)" --tag $(REGISTRY):latest .
+
+.PHONY: tags
+tags:
+	docker tag $(REGISTRY):latest $(REGISTRY):0.0.5
 
 push:
 	docker push $(REGISTRY):latest
+	docker push $(REGISTRY):0.0.5
 
 build-amd64:
 	docker buildx build --platform linux/amd64 --load -t ruby2.6-jemalloc:amd64 .
@@ -55,19 +60,8 @@ push-arm64:
 pull-arm64:
 	docker pull --platform linux/arm64 $(REGISTRY):latest
 
-build-release:
-	docker buildx build \
-	  --platform $(MULTIARCH_PLATFORMS) \
-	  --cache-from type=local,src=$(MULTIARCH_CACHE_DIR) \
-	  --cache-to type=local,dest=$(MULTIARCH_CACHE_DIR)-new,mode=max \
-	  --push \
-	  -t $(REGISTRY):$(MULTIARCH_TAG) \
-	  .
-	@rm -rf $(MULTIARCH_CACHE_DIR)
-	@mv $(MULTIARCH_CACHE_DIR)-new $(MULTIARCH_CACHE_DIR)
-
 verify: build
-	./scripts/verify-ruby-jemalloc.sh ruby2.6-jemalloc:local
+	./scripts/verify-ruby-jemalloc.sh ruby2.6-jemalloc:latest
 
 verify-amd64: build-amd64
 	./scripts/verify-ruby-jemalloc.sh ruby2.6-jemalloc:amd64 linux/amd64