feat: Time for devcontainers!

.devcontainer/Dockerfile

@@ -0,0 +1,47 @@
+# Development container with all tools pre-installed including Docker and Kind
+# Extends the CI base image with Docker support for local development
+# This is NOT for production - see root Dockerfile for that
+# For local dev: builds CI base from local Dockerfile.ci
+# For CI: uses pre-built image from GHCR
+ARG CI_BASE_IMAGE=ci-base-local
+FROM ${CI_BASE_IMAGE} AS ci-base
+
+# Switch to noninteractive for Docker installation
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install Docker (for local development and Kind cluster management)
+RUN apt-get update \
+    && apt-get -y install --no-install-recommends \
+        apt-transport-https \
+        gnupg \
+        lsb-release \
+    && install -m 0755 -d /etc/apt/keyrings \
+    && curl -fsSL https://download.docker.com/linux/debian/gpg -o /etc/apt/keyrings/docker.asc \
+    && chmod a+r /etc/apt/keyrings/docker.asc \
+    && echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/debian bookworm stable" | tee /etc/apt/sources.list.d/docker.list > /dev/null \
+    && apt-get update \
+    && apt-get -y install --no-install-recommends \
+        docker-ce \
+        docker-ce-cli \
+        containerd.io \
+        docker-buildx-plugin \
+        docker-compose-plugin \
+    && apt-get autoremove -y \
+    && apt-get clean -y \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Kind (for local Kubernetes clusters)
+ENV KIND_VERSION=v0.30.0
+RUN curl -Lo /usr/local/bin/kind https://kind.sigs.k8s.io/dl/${KIND_VERSION}/kind-linux-amd64 \
+    && chmod +x /usr/local/bin/kind
+
+# Verify Docker and Kind installations
+RUN echo "=== Additional Dev Tools ===" \
+    && kind version \
+    && docker --version
+
+# Switch back to dialog for any ad-hoc use of apt-get
+ENV DEBIAN_FRONTEND=dialog
+
+# Default command
+CMD ["/bin/bash"]

.devcontainer/Dockerfile.ci

@@ -0,0 +1,83 @@
+# CI-focused base image with essential build tools
+# This is used in CI pipelines and as base for the full dev container
+FROM golang:1.25.1-bookworm
+
+# Avoid warnings by switching to noninteractive
+ENV DEBIAN_FRONTEND=noninteractive
+
+# Install essential packages (no Docker)
+RUN apt-get update \
+    && apt-get -y install --no-install-recommends \
+        git \
+        curl \
+        ca-certificates \
+        vim \
+        less \
+        jq \
+    && apt-get autoremove -y \
+    && apt-get clean -y \
+    && rm -rf /var/lib/apt/lists/*
+
+# Tool versions - centralized for easy updates
+ENV KUBECTL_VERSION=v1.32.3 \
+    KUSTOMIZE_VERSION=5.7.1 \
+    KUBEBUILDER_VERSION=4.4.0 \
+    GOLANGCI_LINT_VERSION=v2.5.0 \
+    HELM_VERSION=v3.12.3
+
+# Install kubectl
+RUN curl -LO "https://dl.k8s.io/release/${KUBECTL_VERSION}/bin/linux/amd64/kubectl" \
+    && chmod +x kubectl \
+    && mv kubectl /usr/local/bin/
+
+# Install Kustomize
+RUN curl -s "https://raw.githubusercontent.com/kubernetes-sigs/kustomize/master/hack/install_kustomize.sh" | bash -s ${KUSTOMIZE_VERSION} /usr/local/bin/
+
+# Install Kubebuilder
+RUN curl -L -o /usr/local/bin/kubebuilder "https://github.com/kubernetes-sigs/kubebuilder/releases/download/v${KUBEBUILDER_VERSION}/kubebuilder_linux_amd64" \
+    && chmod +x /usr/local/bin/kubebuilder
+
+# Install Helm
+RUN curl -fsSL https://get.helm.sh/helm-${HELM_VERSION}-linux-amd64.tar.gz \
+    | tar -xzO linux-amd64/helm > /usr/local/bin/helm \
+    && chmod +x /usr/local/bin/helm
+
+# Install golangci-lint
+RUN curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh \
+    | sh -s -- -b /usr/local/bin ${GOLANGCI_LINT_VERSION}
+
+# Set working directory
+WORKDIR /workspace
+
+# Install Go tools used by the project (using @version doesn't need go.mod)
+RUN go install sigs.k8s.io/controller-tools/cmd/controller-gen@v0.19.0 \
+    && go install sigs.k8s.io/controller-runtime/tools/setup-envtest@latest
+
+# Initialize golangci-lint cache by running it once on an empty directory
+# This downloads linter dependencies without needing source code
+RUN mkdir -p /tmp/golangci-init && cd /tmp/golangci-init \
+    && go mod init example.com/init \
+    && echo 'package main\n\nfunc main() {}' > main.go \
+    && golangci-lint run --timeout=5m || true \
+    && cd / && rm -rf /tmp/golangci-init
+
+# Pre-download Go modules for caching - placed AFTER tool installation
+# This layer will be cached and only rebuilt when go.mod/go.sum changes
+# Moving this down prevents tool reinstallation when dependencies change
+COPY go.mod go.sum ./
+RUN go mod download
+
+# Verify installations
+RUN echo "=== Tool Versions ===" \
+    && go version \
+    && kubectl version --client \
+    && kustomize version \
+    && (kubebuilder version || echo "Kubebuilder: not available (optional)") \
+    && helm version \
+    && golangci-lint version
+
+# Switch back to dialog for any ad-hoc use of apt-get
+ENV DEBIAN_FRONTEND=dialog
+
+# Default command
+CMD ["/bin/bash"]

.devcontainer/README.md

@@ -0,0 +1,49 @@
+# Development Container
+
+Quick-start development environment with all tools pre-installed.
+
+## Quick Start
+
+### VS Code
+1. Install [Dev Containers extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers)
+2. Open project in VS Code: `code .`
+3. Press `F1` → `Dev Containers: Reopen in Container`
+4. Wait for initial build (~5-10 min first time)
+
+### Verify
+```bash
+go version        # 1.25.1
+kind version      # v0.30.0
+kubectl version   # v1.32.3
+golangci-lint version  # v2.4.0
+```
+
+### Run Tests
+```bash
+make test         # Unit tests
+make lint         # Linting
+make test-e2e     # E2E tests (creates Kind cluster)
+```
+
+## Architecture
+
+Two containers:
+- **`Dockerfile.ci`** - CI base (Go tools, no Docker) - Used in GitHub Actions
+- **`Dockerfile`** - Full dev (extends CI base, adds Docker+Kind) - Local only
+
+Local dev builds CI base automatically (`initializeCommand`), no GHCR pulls needed.
+
+## Files
+
+- `Dockerfile.ci` - CI base container
+- `Dockerfile` - Full dev container  
+- `devcontainer.json` - VS Code configuration
+- `README.md` - This file
+
+## Troubleshooting
+
+**Container won't build** → Ensure Docker is running  
+**E2E tests fail** → Check `docker info` works  
+**Slow rebuild** → Normal, only rebuilds when tools/deps change
+
+See [`docs/COMPLETE_SOLUTION.md`](../docs/COMPLETE_SOLUTION.md) for details.

.devcontainer/devcontainer.json

@@ -1,25 +1,47 @@
 {
-  "name": "Kubebuilder DevContainer",
-  "image": "golang:1.25.1",
+  "name": "GitOps Reverser DevContainer",
+  "build": {
+    "dockerfile": "Dockerfile",
+    "context": "..",
+    "args": {
+      "CI_BASE_IMAGE": "ci-base-local"
+    },
+    "target": ""
+  },
+  "initializeCommand": "cd .devcontainer && docker build -f Dockerfile.ci -t ci-base-local ..",
   "features": {
-    "ghcr.io/devcontainers/features/docker-in-docker:2": {},
-    "ghcr.io/devcontainers/features/git:1": {}
+    "ghcr.io/devcontainers/features/docker-in-docker:2": {
+      "moby": false,
+      "dockerDashComposeVersion": "v2"
+    }
   },
 
   "runArgs": ["--network=host"],
 
   "customizations": {
     "vscode": {
       "settings": {
-        "terminal.integrated.shell.linux": "/bin/bash"
+        "terminal.integrated.shell.linux": "/bin/bash",
+        "go.toolsManagement.checkForUpdates": "local",
+        "go.useLanguageServer": true,
+        "go.gopath": "/go",
+        "go.goroot": "/usr/local/go"
       },
       "extensions": [
+        "golang.go",
         "ms-kubernetes-tools.vscode-kubernetes-tools",
-        "ms-azuretools.vscode-docker"
+        "ms-azuretools.vscode-docker",
+        "kilocode.kilo-code"
       ]
     }
   },
 
-  "onCreateCommand": "bash .devcontainer/post-install.sh"
+  "postCreateCommand": "docker network create -d=bridge --subnet=172.19.0.0/24 kind || true",
+
+  "remoteUser": "root",
+
+  "mounts": [
+    "source=/var/run/docker.sock,target=/var/run/docker.sock,type=bind"
+  ]
 }
 

.dockerignore

@@ -11,3 +11,7 @@
 !cmd/
 !api/
 !internal/
+
+# Additional files needed for dev container build (.devcontainer/Dockerfile)
+!.golangci.yml
+!hack/