🏭 Production Deployment: Docker & Kubernetes

Deploying Rust microservices to production environments requires minimal container sizes, high security isolation (non-root runtimes), fast CI build caching, and Kubernetes deployment manifests.

This guide provides production-ready Dockerfiles using cargo-chef and complete Kubernetes deployment manifests.

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1. Multi-Stage Dockerfile with cargo-chef

Compiling Rust dependencies on every Docker build can take 10+ minutes. Using cargo-chef, dependency layers are cached separately from application source code, reducing rebuild times to under 15 seconds.

# 1. Chef Stage: Compute dependency recipe
FROM lukemathwalker/cargo-chef:latest-rust-1.75-bookworm AS chef
WORKDIR /app

FROM chef AS planner
COPY . .
RUN cargo chef prepare --recipe-path recipe.json

# 2. Caching Stage: Build dependencies only
FROM chef AS builder
COPY --from=planner /app/recipe.json recipe.json
RUN cargo chef cook --release --recipe-path recipe.json

# 3. Application Build Stage
COPY . .
RUN cargo build --release --bin ferrox-showcase

# 4. Minimal Security Production Runtime (Distroless / Debian-Slim)
FROM debian:bookworm-slim AS runtime
WORKDIR /app

# Install SSL certificates & CA roots
RUN apt-get update && apt-get install -y --no-install-recommends \
    ca-certificates \
    libssl3 \
    && rm -rf /var/lib/apt/lists/*

# Create non-root user for security isolation
RUN useradd -ms /bin/bash ferroxuser
USER ferroxuser

# Copy release binary from builder
COPY --from=builder /app/target/release/ferrox-showcase /app/server

EXPOSE 3000 9000

ENV FERROX_SERVER_PORT=3000
CMD ["/app/server"]

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2. Kubernetes Production Manifests

2.1 Deployment & Horizontal Pod Autoscaler (HPA)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: ferrox-app
  labels:
    app: ferrox-app
spec:
  replicas: 3
  selector:
    matchLabels:
      app: ferrox-app
  template:
    metadata:
      labels:
        app: ferrox-app
    spec:
      containers:
      - name: ferrox-container
        image: registry.company.com/ferrox-app:v1.0.0
        ports:
        - containerPort: 3000
          name: http
        - containerPort: 9000
          name: metrics
        resources:
          limits:
            cpu: "1"
            memory: "512Mi"
          requests:
            cpu: "100m"
            memory: "64Mi"
        livenessProbe:
          httpGet:
            path: /healthz
            port: http
          initialDelaySeconds: 5
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /readyz
            port: http
          initialDelaySeconds: 5
          periodSeconds: 5
---
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: ferrox-hpa
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: ferrox-app
  minReplicas: 3
  maxReplicas: 20
  metrics:
  - type: Resource
    resource:
      name: cpu
      target:
        type: Utilization
        averageUtilization: 70

---

3. Container Optimization Metrics

Metric	Traditional Node.js Container	Ferrox Distroless Container
Image Size	900 MB	< 35 MB
Idle RAM Usage	120 MB	< 8 MB
Cold Start Time	3.5 seconds	< 0.05 seconds