diff --git a/install.sh b/install.sh
old mode 100644
new mode 100755
index bc7a292..5b2ef16
--- a/install.sh
+++ b/install.sh
@@ -1,4 +1,11 @@
 #!/bin/bash
+set -e
+
+# Require root
+if [[ $EUID -ne 0 ]]; then
+    echo "This script must be run as root." >&2
+    exit 1
+fi
 
 # Installs bb64 on the local machine.
 
@@ -12,3 +19,45 @@
 
 # 5. prints a message to the user
 
+# 1. Determine architecture
+ARCH=$(uname -m)
+if [[ "$ARCH" == "x86_64" ]]; then
+    BIN=bb64.amd64
+elif [[ "$ARCH" == "aarch64" || "$ARCH" == "arm64" ]]; then
+    BIN=bb64.arm64
+else
+    echo "Unsupported architecture: $ARCH" >&2
+    exit 1
+fi
+
+# 2. Get latest release tag from Gitea API
+REPO_API="https://gitea.jde.nz/api/v1/repos/j/bb64/releases"
+if command -v jq >/dev/null 2>&1; then
+    TAG=$(curl -s "$REPO_API" | jq -r '.[0].tag_name')
+else
+    TAG=$(curl -s "$REPO_API" | grep -m1 '"tag_name"' | sed 's/.*"tag_name"[ ]*:[ ]*"\([^"]*\)".*/\1/')
+fi
+if [ -z "$TAG" ] || [ "$TAG" = "null" ]; then
+    echo "Could not determine latest release tag from $REPO_API" >&2
+    exit 1
+fi
+
+echo "Latest version of bb64 is: $TAG"
+
+# 3. Download the appropriate binary to a temp directory
+TMPDIR=$(mktemp -d)
+trap 'rm -rf "$TMPDIR"' EXIT
+URL="https://gitea.jde.nz/j/bb64/releases/download/$TAG/$BIN"
+echo "Downloading $BIN from $URL..."
+
+curl -L -o "$TMPDIR/bb64" "$URL"
+
+# 4. Make it executable
+chmod +x "$TMPDIR/bb64"
+
+# 5. Move to /usr/local/bin
+mv "$TMPDIR/bb64" /usr/local/bin/bb64
+
+# 6. Print success message
+echo "bb64 installed successfully to /usr/local/bin/bb64 (version $TAG, arch $ARCH)"
+