Here is a small confession from many years of working with engineering teams: the tasks I trusted least were the ones I did most often. Building and shipping a container image is a perfect example. You do it weekly, it feels easy, and you are certain you remember the order. Then you hand it to a colleague and discover three steps you never mentioned. In this how-to, we will write a Docker release runbook together, step by step, so that anybody on your team can ship an image correctly, and so that you leave a visible trace of professional habits that helps your career.
No special tools needed. A text editor and one recent release are enough.
Step 1: Do the task once while taking notes
Pick your next real release and do it as usual, but with a notes file open beside you. Write down every action as it happens. Include the boring ones: which branch you check out, which tag format you use, which registry you log in to, which environment you test in. If you pause to think “wait, which one was it?”, write down the answer. That pause is exactly where your memory is carrying weight that the page will need to carry later.
Step 2: Turn the notes into numbered, verb-first steps
Rewrite your notes so that each line is one action starting with a verb. A rough draft for an image release might begin like this:
- Confirm the main branch is green in the pipeline.
- Choose the version number following the team’s tagging pattern.
- Build the image from the release branch.
- Scan the image with the team’s chosen scanner and note any serious findings.
- Push the image to the registry under the new tag.
- Deploy to the staging environment and open the health page.
- Deploy to production during the agreed window.
- Watch the logs and health page for ten minutes.
Resist the temptation to explain why each step exists. Those explanations belong in a separate background note. Under pressure, a reader wants actions.
Step 3: Add the expected result to every step
This small change transforms a list into a procedure. After each action, say what you should see: “the build finishes without errors and prints the image ID”, “the registry shows the new tag within a minute”, “the health page returns a normal status”. When reality differs, the reader knows immediately that something is off, without needing years of instinct.
Step 4: Write the way back
Every release page needs a rollback section. State where the previous image tag can be found, the command to redeploy it and the check to confirm the old version is running again. Also state the point of no return, such as a database change that cannot be undone, and flag it clearly. A runbook that explains how to go forward but not how to retreat is half a document.
Step 5: Name the common traps
Add a short “watch out” box listing the mistakes beginners make. Teams that handle containers every day tend to share a few: forgetting to pin a base image version, leaving secrets inside an image layer, or pushing the wrong tag. The advice in this roundup of frequent Docker mistakes for beginners is a good source for that section, and each item can become a single-line warning next to the relevant step.
Step 6: Link to the deeper material, don’t repeat it
A runbook should stay short. If you want to explain how your team manages image storage, cleanup and tagging, point to a longer article instead of pasting it in. For example, the ideas behind managing container images as an engineering team make excellent background reading, while your runbook holds only the actions.
Step 7: Test it on a colleague who has never done it
Now comes the step that separates a real runbook from a private note. Ask a teammate who has never shipped this image to follow the page in a safe environment, while you watch silently. Do not coach. When they hesitate, make a mark. When they guess, make two. Afterwards, fix the page for every mark, not the person.
Run the test a second time with someone else if the first one produced many edits. A page is ready when a stranger can complete it without a single question.
Step 8: Add an owner, a date and a home
- Owner. One named person keeps it current. They are not the only one who may use it.
- Last tested. A date and the tester’s name at the bottom.
- Home. A shared folder or wiki page named “Release a container image”, linked from the team chat topic.
Step 9: Make it part of your career story
This is where personal branding comes in, and it is easier than people think. A runbook you have written and tested shows several qualities at once: that you think in sequences, that you care about colleagues who come after you, and that you finish what you start. Employers hiring for DevOps and cloud roles tend to trust candidates who can describe their working habits concretely.
A few ways to put it to use:
- Describe it in one sentence on your résumé: “Wrote and tested a release runbook for container images, adopted by the whole team.”
- Share a cleaned-up, generic version in your portfolio, with company names and secrets removed.
- Write a short post about what you learned from testing it on a colleague.
- Bring it up in interviews when asked about teamwork or reliability.
Step 10: Improve it after every surprise
After any release that did not go to plan, spend five minutes on the page. Add a missing warning, correct a command, tighten a step. Log the change with two short lines at the bottom. After a few months, you will have a document that reflects real experience, and that is what makes it valuable.
Step 11: Grow it into a small library
Once the release page works, the next ones come quickly because you already know the shape. Good follow-ups for a container workflow are the image cleanup routine, the base-image update, the registry access request and the rollback drill. Keep the same headings on each page so a reader who has used one can find their way around the others in seconds.
Try to resist the urge to perfect the first page before writing the second. A rough library of four pages that people actually open is worth much more than one beautiful page that nobody has tested. Momentum is the whole game here, and a conversational check-in at the weekly team meeting, asking “did any page let you down this week?”, keeps it going without much effort. Over a few months the habit becomes part of how the team talks about releases, and nobody remembers it ever being optional.
A tip on reading widely
It pays to look at how adjacent fields manage the same discipline. Data engineers, for example, write procedures for keeping pipelines healthy, and TheDataOps.org is one blog where you can see how that world thinks about repeatable operations. Borrowing a good habit from a neighbour is one of the cheapest ways to grow.
A ready-to-copy skeleton
- Title: Release a container image
- Purpose: one sentence
- Before you start: access, tools, window, approvals
- Steps: numbered, verb-first, each with an expected result
- Watch out: three or four common traps
- Rollback: where the previous tag lives, the command, the check
- If stuck: who to call
- Owner and last tested: name, date, tester
Do the notes this week, the draft tomorrow and the colleague test by Friday. By next Monday you will have something small and real that makes your team stronger and says something good about you. That combination is hard to beat for the price of a couple of hours.
