diff --git a/scripts/download-roc.sh b/scripts/download-roc.sh
new file mode 100755
index 0000000..23fdd98
--- /dev/null
+++ b/scripts/download-roc.sh
@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROC_VERSION="${1:?Usage: $0 <roc-version> [target-arch]}"
+TARGETARCH="${2:-amd64}"
+
+# Map Docker buildx arch names to Roc tarball arch names
+case "$TARGETARCH" in
+  amd64)  ROC_ARCH="x86_64"  ;;
+  arm64)  ROC_ARCH="aarch64" ;;
+  *)      echo "Unsupported architecture: $TARGETARCH" >&2; exit 1 ;;
+esac
+
+TARBALL="roc-linux_${ROC_ARCH}-${ROC_VERSION}.tar.gz"
+URL="https://github.com/roc-lang/roc/releases/download/${ROC_VERSION}/${TARBALL}"
+
+echo "Downloading Roc ${ROC_VERSION} for ${ROC_ARCH}..."
+curl -fsSL "$URL" -o /tmp/roc.tar.gz
+
+echo "Extracting..."
+tar -xzf /tmp/roc.tar.gz -C /tmp/
+
+# The tarball contains a single directory with an unpredictable nightly name
+# e.g. roc_nightly-linux_x86_64-2025-09-09-d73ea109/
+EXTRACTED_DIR=$(find /tmp -maxdepth 1 -type d -name "roc_*" | head -1)
+if [ -z "$EXTRACTED_DIR" ]; then
+  echo "ERROR: Could not find extracted Roc directory in /tmp" >&2
+  exit 1
+fi
+
+echo "Installing to /opt/roc..."
+mkdir -p /opt/roc/bin /opt/roc/lib
+
+install -m 0755 "$EXTRACTED_DIR/roc" /opt/roc/bin/roc
+
+# LSP may or may not be present in older releases; install if found
+if [ -f "$EXTRACTED_DIR/roc_language_server" ]; then
+  install -m 0755 "$EXTRACTED_DIR/roc_language_server" /opt/roc/bin/roc_language_server
+fi
+
+# WASI libc is needed for some platforms
+if [ -d "$EXTRACTED_DIR/lib" ]; then
+  cp -r "$EXTRACTED_DIR/lib/"* /opt/roc/lib/
+fi
+
+# License
+if [ -f "$EXTRACTED_DIR/LICENSE" ]; then
+  cp "$EXTRACTED_DIR/LICENSE" /opt/roc/LICENSE
+fi
+
+# Cleanup
+rm -rf /tmp/roc.tar.gz "$EXTRACTED_DIR"
+
+echo "Roc ${ROC_VERSION} installed successfully."
+/opt/roc/bin/roc --version