diff --git a/Dockerfile b/Dockerfile
index 493e885..95062d7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,21 +1,56 @@
 FROM node:22-slim
 
-# Install runtime dependencies
+# System dependencies:
+#   - curl/ca-certificates: downloads (Claude Code installer, nvm, git-spice)
+#   - git + ripgrep: Claude Code requirements
+#   - build-essential, libssl-dev, libreadline-dev, zlib1g-dev: rbenv/ruby-build deps
 RUN apt-get update && apt-get install -y --no-install-recommends \
     curl \
     ca-certificates \
     git \
     ripgrep \
     bash \
+    build-essential \
+    libssl-dev \
+    libreadline-dev \
+    zlib1g-dev \
+    libffi-dev \
+    libyaml-dev \
     && rm -rf /var/lib/apt/lists/*
 
-# Create a non-root user with a real home directory
+# --- rbenv (installed into home volume on first run, via entrypoint) ---
+# RBENV_ROOT points into the home volume so the install persists across rebuilds.
+ENV RBENV_ROOT=/home/coder/.rbenv
+ENV PATH="$RBENV_ROOT/bin:$RBENV_ROOT/shims:$PATH"
+
+# Initialise rbenv shims for all bash sessions (no-op if not yet installed)
+RUN echo '[ -d "$RBENV_ROOT/bin" ] && eval "$(rbenv init - bash)"' >> /etc/bash.bashrc
+
+# --- nvm (installed into home volume on first run, via entrypoint) ---
+# NVM_DIR points into the home volume so the install persists across rebuilds.
+ENV NVM_DIR=/home/coder/.nvm
+
+# Source nvm for all bash sessions (nvm.sh is a no-op if not yet installed)
+RUN echo '[ -s "$NVM_DIR/nvm.sh" ] && . "$NVM_DIR/nvm.sh"' >> /etc/bash.bashrc
+
+# --- git-spice ---
+# Releases are named git-spice.Linux-<arch>.tar.gz; uname -m gives the right arch directly.
+RUN ARCH=$(uname -m) && \
+    GS_VERSION=$(curl -fsSL https://api.github.com/repos/abhinav/git-spice/releases/latest \
+        | grep '"tag_name"' | sed 's/.*"v\([^"]*\)".*/\1/') && \
+    mkdir -p /tmp/gs-install && \
+    curl -fsSL "https://github.com/abhinav/git-spice/releases/download/v${GS_VERSION}/git-spice.Linux-${ARCH}.tar.gz" \
+        | tar -xz -C /tmp/gs-install && \
+    find /tmp/gs-install -maxdepth 1 -type f -executable -exec cp {} /usr/local/bin/gs \; && \
+    chmod +x /usr/local/bin/gs && \
+    rm -rf /tmp/gs-install
+
+# --- non-root user ---
 RUN useradd -m -s /bin/bash -u 1001 coder
 
-# Ensure ~/.local/bin is on PATH (where the native installer puts the binary)
-ENV PATH="/home/coder/.local/bin:/home/coder/.claude/bin:${PATH}"
+# Claude Code native installer lands in ~/.local/bin or ~/.claude/bin
+ENV PATH="/home/coder/.local/bin:/home/coder/.claude/bin:$PATH"
 
-# Copy entrypoint (as root, then lock down)
 COPY --chmod=755 entrypoint.sh /usr/local/bin/entrypoint.sh
 
 USER coder
diff --git a/entrypoint.sh b/entrypoint.sh
index 24de07e..bc1d370 100644
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -1,15 +1,42 @@
 #!/bin/bash
 set -e
 
+# Install nvm if not already present in the home volume.
+if [ ! -s "$NVM_DIR/nvm.sh" ]; then
+  echo "nvm not found — running installer..."
+  curl -fsSL https://raw.githubusercontent.com/nvm-sh/nvm/HEAD/install.sh |
+    NVM_DIR="$NVM_DIR" PROFILE=/dev/null bash
+  echo "nvm installed successfully."
+fi
+. "$NVM_DIR/nvm.sh"
+
+# Install rbenv + ruby-build if not already present in the home volume.
+if [ ! -d "$RBENV_ROOT/bin" ]; then
+  echo "rbenv not found — installing..."
+  git clone --depth=1 https://github.com/rbenv/rbenv.git "$RBENV_ROOT"
+  git clone --depth=1 https://github.com/rbenv/ruby-build.git "$RBENV_ROOT/plugins/ruby-build"
+  echo "rbenv installed successfully."
+fi
+eval "$(rbenv init - bash)"
+
+# Install nvm if not already present in the home volume.
+if [ ! -s "$NVM_DIR/nvm.sh" ]; then
+  echo "nvm not found — running installer..."
+  curl -fsSL https://raw.githubusercontent.com/nvm-sh/nvm/HEAD/install.sh |
+    NVM_DIR="$NVM_DIR" PROFILE=/dev/null bash
+  echo "nvm installed successfully."
+fi
+. "$NVM_DIR/nvm.sh"
+
 # Install Claude Code if not already present in the home volume.
 # Because the home directory is a volume, this install persists across
 # container restarts and rebuilds.
 if ! command -v claude &>/dev/null; then
-    echo "Claude Code not found — running installer..."
-    curl -fsSL https://claude.ai/install.sh | bash
-    echo "Claude Code installed successfully."
+  echo "Claude Code not found — running installer..."
+  curl -fsSL https://claude.ai/install.sh | bash
+  echo "Claude Code installed successfully."
 else
-    echo "Claude Code $(claude --version 2>/dev/null || echo '(version unknown)') ready."
+  echo "Claude Code $(claude --version 2>/dev/null || echo '(version unknown)') ready."
 fi
 
 exec "$@"