Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
Testing in the Pipeline: Fast Feedback, Quality Gates and Flaky Tests
Ordering tests in the pipeline from cheap to expensive (formatting, unit, integration with Testcontainers, e2e with Playwright) and adding quality gates such as warnings, coverage and bundle budgets gives fast, trustworthy feedback; a flaky test needs its root cause fixed rather than a retry. How a test without assertions inflates coverage, a real flaky test failing 2 of 30 runs, and an empty Playwright shard.
Build Once, Deploy Many: Artifacts, Versioning and Immutable Packages
Building an artifact once and carrying that same artifact, by tag or digest, from staging to production guarantees that what was tested on staging is what reaches production; even building the same commit twice yields different images. Reproducible builds with lock files and npm ci, stamping versions with the commit SHA, the :latest trap, and a runtime config.json for Angular.
Pipeline Anatomy: Triggers, Stages, Jobs, Steps and Failing Fast
A pipeline starts with triggers and is made of dependent jobs (stages in Jenkins) and steps that run in order; putting the build logic in a script that runs locally, letting the pipeline only orchestrate, moving cheap checks first and failing fast across parallel branches all speed up feedback. A GitHub Actions, Jenkins and Azure DevOps term mapping, with real output from act and Jenkins.
CI, Continuous Delivery and Continuous Deployment: The Differences and Why They Matter
CI means everyone integrates into the mainline every day and every push runs an automated build and tests; continuous delivery keeps every commit releasable and leaves going to production as a decision, while continuous deployment removes that button too. An integration hell scenario, Fowler's 2024 practices, a CI workflow run with act, and the MinimumCD checklist.
Preparing for Git 3.0: What Changes, What Goes, What to Do Today
We separate the official status of Git 3.0 (BreakingChanges.adoc: no date yet) from the plan reported by GitLab and LWN. We try the main, SHA-256 and reftable defaults, safe.bareRepository, mandatory Rust, the commands being removed and why git checkout stays on Git 2.54, and end with a preparation checklist.
Git 2.50–2.56: git history, Config-Based Hooks and git add --resolved
We go from Git 2.50 to the current 2.56: git history reword and split (fixup in 2.55, drop in 2.56), config-based and parallel hooks, stash export/import, pull.autostash and what happens on a conflict, git last-modified, git repo info, reflog drop, branch --delete-merged, add --resolved and the -h exit code change.
Git 2.40–2.49: reftable, SHA-256, git replay and the New git config
We look at the 2.40–2.49 period, when the foundations of Git 3.0 were laid, with real output: the reftable ref store and git refs migrate, where SHA-256 repos stand today, git config's get/set/unset/list subcommands, worktree add --orphan, git replay, safe.directory prefixes, git backfill and Rust's first step.
Git 2.23–2.39: From checkout to switch and restore, Old Habits to New Ones
We put old and new side by side for what arrived between Git 2.23 and 2.39: the move from checkout to switch and restore, init.defaultBranch, pull's divergent branches error, sparse-checkout, maintenance, fsmonitor, ort and remerge-diff, rebase --update-refs, force-if-includes, safe.directory and SSH signing.
Git Hooks and Commit Signing: From pre-commit to SSH Signatures
We write pre-commit and commit-msg hooks with real output, share them with the team through core.hooksPath, and try Git 2.54's config-based hooks and git hook list. Then we sign commits with an SSH key, verify them with an allowed signers file and look at what GitHub's Verified badge requires.
Git bisect and git worktree: Finding the Bad Commit and Two Branches at Once
We find the commit that introduced a bug with git bisect's binary search: marking good and bad, bisect log and reset, automatic search by exit code with git bisect run, and exit 125. Then we use git worktree to make a hotfix in a separate folder without disturbing unfinished work, and look at worktree list/remove/prune and when it beats stash.
Git Tags and Releases: Marking Versions, git describe and GitHub Releases
We mark releases with git tag: lightweight versus annotated tags, the tag object, semver, why push doesn't send tags, --tags versus --follow-tags, reading git describe output, GitHub Releases, deleting tags and why moving a published tag is dangerous.
Git reflog: Bringing Back Lost Commits and Deleted Branches
We bring commits back with git reflog after an accidental reset --hard: HEAD@{n} versus HEAD~n, undoing the last merge with ORIG_HEAD, finding a deleted branch in the reflog, backing out of a rebase with the branch's own reflog, and why the reflog is local and expires.