diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 000000000..b52fc61c3
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,63 @@
+# Heavy build outputs — must never reach the build context. `target/` alone is
+# >100 GB on a dev machine.
+target/
+node_modules/
+dist/
+runs/
+
+# Per-host scratch the pi codebase uses for parallel agents / worktrees.
+.fallow/
+.worktrees/
+.wt/
+.opencode/
+.pi_config/
+.omp/plugins/
+
+# VCS, editors, IDEs — irrelevant to the build, churn on every IDE keystroke.
+.git/
+.npm/
+.vscode/
+.zed/
+.idea/
+
+# OS + transient noise. Finder rewrites .DS_Store whenever you peek at a
+# folder; profilers drop `CPU.*` blobs at random times. Letting any of these
+# into the build context busts BuildKit's content hash and forces a full
+# native rebuild for no good reason.
+.DS_Store
+*.swp
+*.swo
+*~
+*.tmp
+
+# Logs + profiling artifacts.
+*.log
+*.cpuprofile
+*.heapprofile
+*.heapsnapshot
+CPU.*
+
+# Build / test side outputs.
+*.tsbuildinfo
+coverage/
+.nyc_output/
+__pycache__/
+compaction-results/
+changes/
+
+# Generated files (the in-image build regenerates them).
+packages/coding-agent/src/internal-urls/docs-index.generated.ts
+packages/natives/native/.build/
+packages/natives/native/pi_natives.darwin-*.node
+packages/natives/native/pi_natives.dev.node
+packages/ai/test/.temp-images/
+python/omp-rpc/src/omp_rpc.egg-info/
+
+# Scratch files the repo creates ad-hoc.
+syntax.jsonl
+out.jsonl
+out.html
+pi-*.html
+
+# Secrets. Should never be in the image regardless.
+.env
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 000000000..8634a9a07
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,100 @@
+# syntax=docker/dockerfile:1.7
+###############################################################################
+# oh-my-pi — build-artifacts image
+#
+# Produces, in `/out/`, the cross-host build outputs that downstream consumers
+# bake into their runtime images:
+#
+#   - pi_natives.linux-<arch>.node   — N-API addon compiled from `crates/pi-natives`
+#   - omp_rpc-<version>-py3-none-any.whl — Python RPC wheel from `python/omp-rpc`
+#
+# This image deliberately has no entrypoint and no apt-installed extras: it is
+# meant to be referenced as a `COPY --from=` stage by other Dockerfiles.
+#
+# Build:
+#     docker build -t oh-my-pi/artifacts:dev .
+#
+# Consume from another Dockerfile:
+#     ARG PI_ARTIFACTS_IMAGE=oh-my-pi/artifacts:dev
+#     FROM ${PI_ARTIFACTS_IMAGE} AS pi-artifacts
+#     COPY --from=pi-artifacts /out/pi_natives.linux-*.node /opt/bun/bin/
+#     COPY --from=pi-artifacts /out/*.whl /tmp/wheels/
+###############################################################################
+
+############################
+# 1) natives-builder — Rust + Bun → pi_natives.linux-<arch>.node
+############################
+FROM rust:1.86-slim-bookworm AS natives-builder
+
+ARG BUN_VERSION=1.3.14
+ENV BUN_INSTALL=/opt/bun \
+    PATH=/opt/bun/bin:/usr/local/cargo/bin:/usr/local/bin:/usr/bin:/bin \
+    CARGO_TERM_COLOR=never
+
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends \
+        curl ca-certificates pkg-config libssl-dev unzip git \
+    && rm -rf /var/lib/apt/lists/*
+
+RUN curl -fsSL https://bun.sh/install | bash -s "bun-v${BUN_VERSION}" \
+    && /opt/bun/bin/bun --version
+
+WORKDIR /pi
+
+# ─── Layer 1: workspace manifests + lockfiles only ───────────────────────────
+# Editing source files (under `packages/<x>/src/…` or `crates/<x>/src/…`) won't
+# bust the `bun install` layer below, because none of those globs match. Only
+# touching a `package.json`, `Cargo.toml`, or a root lockfile invalidates this
+# layer. `--parents` preserves the matched path under /pi/ (BuildKit 1.7+).
+COPY --parents \
+    package.json bun.lock bunfig.toml \
+    tsconfig.base.json tsconfig.json \
+    Cargo.toml Cargo.lock rust-toolchain.toml \
+    packages/*/package.json \
+    packages/tsconfig.workspace.json \
+    crates/*/Cargo.toml \
+    /pi/
+
+# ─── Layer 2: hydrate node_modules from the manifests above ──────────────────
+RUN bun install --frozen-lockfile --ignore-scripts
+
+# ─── Layer 3: full source ────────────────────────────────────────────────────
+# `.dockerignore` keeps `target/`, `node_modules/`, `dist/`, `runs/`, editor /
+# OS noise (`.DS_Store`, `CPU.*`, `*.cpuprofile`, …), and pre-built host-only
+# natives output out of the build context. node_modules from Layer 2 is
+# preserved across this COPY because it's never in the context to begin with.
+COPY . /pi/
+
+# ─── Layer 4: compile pi-natives to a Linux N-API addon ──────────────────────
+# Persistent caches make repeat builds incremental even when the source layer
+# invalidates: cargo's package index + git-deps + the workspace's target dir.
+RUN --mount=type=cache,target=/root/.cargo/registry \
+    --mount=type=cache,target=/root/.cargo/git \
+    --mount=type=cache,target=/pi/target \
+    set -eux; \
+    rustup show; \
+    bun --cwd=packages/natives run build; \
+    mkdir -p /out; \
+    cp packages/natives/native/pi_natives.linux-*.node /out/
+
+############################
+# 2) python-builder — omp-rpc wheel
+############################
+FROM python:3.12-slim-bookworm AS python-builder
+
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends git \
+    && rm -rf /var/lib/apt/lists/*
+
+RUN pip install --upgrade pip build
+
+WORKDIR /src
+COPY python/omp-rpc /src
+RUN python -m build --wheel --outdir /out
+
+############################
+# 3) artifacts — final image, nothing but the two outputs.
+############################
+FROM scratch AS artifacts
+COPY --from=natives-builder /out/pi_natives.linux-*.node /out/
+COPY --from=python-builder /out/*.whl /out/