Tightening a dev VM that was quietly living without a firewall
What a routine security audit found on a small always-on dev VM: passwordless databases, no host firewall, over-privileged jobs, and how it got fixed.
Tag: docker
Incus vs. Docker: System Containers vs. App Containers
A practical comparison of Incus and Docker: when system containers suit development environments better than single-process application containers.
Faster Rails Docker Feedback Loop: Runtime Deps and HMR
How I reduced Docker development friction across three Rails apps by removing rebuild-heavy steps, adding runtime dependency sync, and enabling webpack HMR.
Migrating a Rails App from Yarn + Webpacker to pnpm + Vite
A migration path from Webpacker and Yarn to pnpm and Vite in a Rails app, including the dependency, Docker, and asset-hash pitfalls we hit along the way.
Fixing the Asia/Rangoon Postgres Error on Alpine Linux
If you recently updated your Docker images and were greeted by a PG::InvalidParameterValue: ERROR: time zone "Asia/Rangoon" not recognized, you aren't alone.
localhost vs 127.0.0.1 vs 0.0.0.0: Network Binding Explained
Why localhost, 127.0.0.1, 0.0.0.0, and * behave differently for MySQL clients and services, and how to find and fix a local port conflict between Docker and SSH.
Speeding Up Docker: Fixing Slow Host-to-Container File Sync
Bind-mounted host directories make Docker Desktop file access painfully slow on macOS and Windows, and this covers volumes, docker-sync, Mutagen, and WSL 2 fixes.
Nokogiri vs libxml2: Debugging a Dynamic Library Conflict
Why Nokogiri XPath queries failed in Docker but not on an M1 Mac: a libxml2 version mismatch caused by indirect dynamic library loading in Ruby.
Build and Push Docker Images to Quay.io with GitHub Actions
A working GitHub Actions workflow that builds a Docker image and pushes it to Quay.io using a scoped robot account and repository secrets.
Kaniko: building container images without a Docker daemon
Kaniko builds and pushes container images without a Docker daemon, and the setup for it differs across GitHub Actions, Google Cloud Build, and CircleCI.
ARG, ENV, and BuildKit secrets: how each behaves in Docker
ARG, ENV, exported shell variables, and BuildKit secret mounts each persist differently in a Docker image, and only one of them is actually safe for tokens.
Linux kill signals: graceful shutdown in containerized workers
SIGTERM, SIGKILL, and grace periods control whether a containerized worker finishes its job before Kubernetes or Supervisord kills it outright.
Retry mechanisms for flaky CI and Docker builds
Wrapping curl, bundle install, and Docker builds in retry logic turns transient network failures in CI into automatic retries instead of full pipeline restarts.
Docker secrets: how layers leak them and how BuildKit fixes it
Docker's layer history persists secrets baked into ARG and ENV instructions, and BuildKit secret mounts are the practical fix that keeps them out of the image.
Docker Buildx --on-error: drop into a shell when a build fails
The --on-error flag in Docker Buildx drops you into a shell inside the failing build step so you can inspect state instead of guessing from logs.
How to Debug Docker Image Builds
Practical techniques for debugging Docker image builds: BuildKit output flags, inspecting intermediate layers, nsenter tricks, and multi-stage build targets.
Running Multiple Processes in a Single Container
Six ways to run multiple processes in one Docker container, from GNU Parallel and Foreman to a custom entrypoint script, Supervisord, and tmux, with trade-offs.
Self-Hosted Whisper: A Speech-to-Text API with Ruby and Kubernetes
How to run OpenAI's Whisper as a self-hosted speech-to-text REST API with Docker, a Ruby client, and a Kubernetes deployment for transcribing audio.
Building and Deploying pgpool Images with GitHub Actions
A GitHub Actions workflow that builds multi-architecture pgpool images for several versions in parallel and pushes them to GitHub Container Registry.
Rails in Kubernetes: Migrations, Jobs, and Puma
Running a Ruby on Rails app in Kubernetes means containerizing it correctly and handling migrations, background jobs, and Puma as separate concerns.
Config Approaches: Files, Env Vars, and Config Servers
A comparison of YAML config files, Rails encrypted credentials, environment variables, and centralized config servers, with the trade-offs of each approach.