PostgreSQL Setup and Configuration

PostgreSQL Setup and Configuration#

Every PostgreSQL deployment boils down to three things: get the binary running, configure who can connect, and tune the memory settings.

Installation Methods#

Package Managers#

On Debian/Ubuntu, use the official PostgreSQL APT repository:

sudo apt install -y postgresql-common
sudo /usr/share/postgresql-common/pgdg/apt.postgresql.org.sh
sudo apt install -y postgresql-16

On macOS: brew install postgresql@16 && brew services start postgresql@16

On RHEL/Fedora:

sudo dnf install -y https://download.postgresql.org/pub/repos/yum/reporpms/EL-9-x86_64/pgdg-redhat-repo-latest.noarch.rpm
sudo dnf install -y postgresql16-server
sudo /usr/pgsql-16/bin/postgresql-16-setup initdb
sudo systemctl enable --now postgresql-16

Config files live at /etc/postgresql/16/main/ (Debian) or /var/lib/pgsql/16/data/ (RHEL).

Securing Docker-Based Validation Templates

Securing Docker-Based Validation Templates#

Validation templates define the environment agents use to test infrastructure changes. If a template runs containers as root, mounts the Docker socket, or skips resource limits, every agent that copies it inherits those risks. This reference covers the security patterns every docker-compose validation template must follow.

1. Non-Root Execution#

Containers run as root by default. A vulnerability in a root-running process gives an attacker full control inside the container and a much larger attack surface for container escapes.

Validation Path Selection: Choosing the Right Approach for Infrastructure Testing

Validation Path Selection#

Not every infrastructure change needs a full Kubernetes cluster to validate. Some changes can be verified with a linter in under a second. Others genuinely need a multi-node cluster with ingress, persistent volumes, and network policies. The cost of choosing wrong is real in both directions: too little validation lets broken configs reach production, while too much wastes minutes or hours on environments you did not need.

Container Build Optimization: BuildKit, Layer Caching, Multi-Stage, and Build Performance

Container Build Optimization#

A container build that takes eight minutes in CI is not just slow – it compounds across every push, every developer, every day. The difference between a naive Dockerfile and an optimized one is often the difference between a two-minute build and a twelve-minute build. The techniques here are not theoretical. They are the specific changes that eliminate wasted time.

BuildKit Over Legacy Builder#

BuildKit is the modern Docker build engine and the default since Docker 23.0. If you are running an older version, enable it explicitly with DOCKER_BUILDKIT=1. BuildKit provides several capabilities the legacy builder lacks.

Minikube with Docker Driver on Apple Silicon

Why the Docker Driver on ARM64#

When running Minikube on Apple Silicon (M1/M2/M3/M4), the driver you choose determines whether your containers run natively or through emulation. The Docker driver runs containers directly on the host architecture — ARM64 — with zero emulation overhead.

This matters because QEMU user-mode emulation, which kicks in when you try to run amd64 images on ARM64, cannot reliably execute Go binaries. The specific failure is a crash in lfstack.push, deep in Go’s runtime memory management. This is not a fixable application bug — it is a fundamental incompatibility between QEMU’s user-mode emulation and Go’s lock-free stack implementation.

Multi-Architecture Container Images: Buildx, Manifest Lists, and Registry Patterns

Multi-Architecture Container Images#

You can no longer assume containers run only on x86. AWS Graviton instances are ARM64. Developer laptops with Apple Silicon are ARM64. Ampere cloud instances are ARM64. A container image tagged myapp:latest needs to work on both architectures, or you end up maintaining separate tags and hoping nobody pulls the wrong one.

Manifest Lists#

A manifest list (also called an OCI image index) lets a single tag point to multiple architecture-specific images. When a client pulls myapp:latest, the registry returns the image matching the client’s architecture.