๐Ÿ”€Merger๐Ÿ”€, a schemaless strategic merge plugin - Kustomize

Kustomize is a great tool. I've been using Kustomize for almost 4 years and am happy with it. However, it's known for its strict merging methods, where it needs to have an OpenAPI schema to merge files properly.

There were many use cases where I needed a more flexible way to merge resources (away from Kustomize's strict merging). So, I've developed a new Kustomize generator plugin (Containerized KRM and Exec KRM) that extends Kustomize's merge strategies (schemaless StrategicMerge).

I wanted to:

  • Generate multiple resources from a single resource without the need to multi-import (you can patch multiple resources with a single patch but not the other way around)
  • An easy way to merge CustomResources without the need to provide the OpenAPI schema for it (that's actually a lot of work)
  • An easy way to merge non-k8s resources and put them in a ConfigMap.
  • A way to split long files into smaller ones.


Say Hi to ๐Ÿ”€Merger๐Ÿ”€

Merger is a generator provides schemaless merges with different strategies (StrategicMerge) like replace, append, and combine.

Here is an example:

apiVersion: generators.kustomize.aabouzaid.com/v1alpha1
kind: Merger
  name: merge
      config.kubernetes.io/function: |
          image: ghcr.io/aabouzaid/kustomize-generator-merger
          - type: bind
            src: ./
            dst: /mnt
  - name: example
      # Available options: overlay,patch.
      # - Overlay: Produce multiple outputs by merging each source with the destination.
      # - Patch: Produce a single output by merging all sources together then with the destination.
      method: overlay
        # The same as in the KRM container above, omit it if Exec KRM is used.
        root: /mnt
        - src01.yaml
        - src02.yaml
        destination: dst.yaml
      # Available options: replace,append,combine.
      # - Replace: All keys in source will merge and replace what's in the destination.
      # - Append: Maps from source merged with destination, but the lists will be appended from source to destination.
      # - Combine: Maps from source merged with destination, but the lists will be combined together.
      strategy: combine
      # Available options: raw.
      # In the next releases also ConfigMap and Secret will be supported.
      format: raw

For more details, check the common use cases section.


Some takeaways I learned while developing this project:

  • KubeBuilder markers could be used with the client side to auto-generate the OpenAPI YAML schema from the code.
  • Golang compression methods (like UPX and LZMA) can reduce the binary size up to 80% compared to the standard build method.
  • Cosign keyless artifacts sign is pretty easy to add to the CI pipeline (no need to manage any extra keys).
  • OpenSSF Scorecard offers a great integration assessing the security health metrics of open-source projects.

Enjoy :-)

Continue Reading »


My Master's Dissertation: Modern Data Platform with DataOps, Kubernetes, and Cloud-Native Ecosystem

Almost 3 years ago (September 2020), I enrolled in a part-time master's program in data engineering at Edinburgh Napier University. Finally, two weeks ago, I got an email informing me that I successfully completed my master's and the program board of examiners awarded me Master of Science with Distinction in Data Engineering ๐ŸŽ‰๐ŸŽ‰๐ŸŽ‰

My graduation ceremony would have been today, but I postponed it to October 2023 for some personal matters. So it's just a matter of time till the official graduation.

So today, I'd like to share my master's dissertation: Modern Data Platform with DataOps, Kubernetes, and Cloud-Native Ecosystem.

The dissertation builds a proof of concept for the core of Modern Data Platform using DataOps, Kubernetes, and Cloud-Native ecosystem to build a resilient Big Data platform based on Data Lakehouse architecture, which is the basis for Machine Learning (MLOps) and Artificial Intelligence (AIOps).

It was a super challenging topic, given the fact that Data Lakehouse architecture emerged just in 2020! But it was great to dive into it. I've been into data for years, and it's exciting to step up my skills from T-Shaped to Pi-Shaped (DevOps and DataOps) :-)

Continue Reading »


Your DevOps learning roadmap is broken! - Career

Can you read it? Probably not, it's already broken!

As of 2023, the DevOps Engineer role remains one of the top 10 most in-demand jobs across all industries (not just the tech field!) And that was the case for the last 5 years at least and is expected to continue for the foreseeable future.

While DevOps is a hot topic all the time, it's in particular hard to start DevOps engineer as your first job. Many engineers believe that it's not possible at all to begin as a DevOps professional without first working as a developer or in operations (I totally disagree with that!).

Almost every day, I see people struggling on their way to start as fresh/junior DevOps engineers. They usually follow some roadmap (typically roadmap.sh/devops). But still, they cannot land their first job, and sadly, many of them eventually give up!

This blog post explains why most of roadmaps don't work for DevOps roles and won't help you start your first job as a DevOps engineer. Also, the post discusses the best way to start in a DevOps role without prior work experience. While it might not work for everyone, I can say that it has been successful with all the people I have mentored in the last couple of years.



In 2023 starting a DevOps engineer role is challenging because the DevOps model has various implementations and patterns. It's even more complicated (but still possible) if that's your first job without previous software industry experience. Yet, many learning roadmaps like roadmap.sh/devops still follow a linear path (i.e., learn some topic to the end, then move to another, and so on) which doesn't work well with the DevOps role because a skilled DevOps engineer is a T-Shaped skilled. Adopting a dynamic MVP learning roadmap increases your chances of entering the market and starting your first job as a DevOps engineer without previous software hands-on experience.

DevOps Topologies

First, let's start with the DevOps model itself. Being a high-level methodology that can be implemented in various ways makes it super challenging. Hence, the DevOps engineer role has no unified definition or standard requirements.

I will not delve into the clichรฉ DevOps is not a role, it is a culture (because in reality, it doesn't work like that! DevOps is not just a culture, and it is also a role), but here I want to emphasize that not all DevOps engineers are the same!

Here I want to mention "DevOps Topologies" which covers different team structures that implement DevOps. It shows many bad and good DevOps patterns.

Given that no one-size-fits-all team topology works for every organization, it's wrong to say it's not possible to start your career as a DevOps engineer. But there are situations where it's extremely challenging to do so, such as being the sole DevOps engineer in a team or even in a company.

So, what can you do to increase your chances of landing your first job as a DevOps engineer? You should have T-shaped skills and leave no stone unturned in your learning journey!

T-Shaped Skills

The "T-Shaped skills" helps DevOps engineers to efficivtly handle various challanges.

The T-shaped skills refer to combining broad and deep skills in a specific field. The horizontal bar of the "T" represents a broad range of general knowledge and skills across different disciplines or areas, and the vertical stem of the "T" represents deep expertise in a specific area. It's simply a mix between being a specialist and generalist at the same time!

The T-shaped skills will help you to work in companies with different DevOps patterns. You can easily transition between different areas in the DevOps spectrum. Not only that but also it will help you to handle new challenges effectively. In fact, the best DevOps engineers I have come across possessed T-shaped skills.

Does it mean there's no I-shaped DevOps engineer who specializes in certain areas and no little knowledge in other areas? I would say it's possible, but it may limit the available opportunities and companies you can work with.

Actually, as you progress in your career, it's better to develop more specialization (i.e., more vertical stems), and after a couple of years in the industry, your next step should be Pi-Shaped skills (search also for M-Shaped and Comb-Shaped skills, but it's a topic for another post).

To summarize this section, you should aim to gain exposure to various areas of DevOps practices and technologies without delving too deep into each one, yet, you need to dive in-depth into some of them (according to the market or organizations your target). And due to that, your roadmap shouldn't be linear but follow the MVP-style approach!

MVP Learning Roadmap

You probably heard before about the "Minimum Viable Product" or MVP, a basic version of a product with enough features to satisfy early users and gather feedback for further development, which's commonly associated with Agile methodologies. Interestingly, this approach can also be applied to learning roadmaps too!

Over the years, I saw people want to start their career as DevOps but completely lost! That's probably because they try to progress in a linear fashion. Typically they will follow some roadmap like roadmap.sh/devops and start learning the topics one by one top down. I.e., they spend a couple of weeks with Linux, then a month learning programming language, then some time with the containers, and more time with Kubernetes. And several months passed, and they found themselves stuck in the middle of the roadmap but still unable to get any job because many topics were untouched!

The truth is that the linear vertical learning path DOES NOT WORK in the DevOps field! You need to follow an MVP-style learning roadmap where you learn in iterations and touch multiple parts at the same time (not necessarily equally). Each iteration should focus on a primary topic while exploring related side topics. So after a month, you already know about each topic in the roadmap, and after the 2nd month, you have the basics, and after the 3rd month, you have a good base, and so on.

By adopting an MVP-style learning roadmap, you can ensure that you cover various aspects of DevOps while continuously building upon your knowledge. This approach allows for a more well-rounded understanding and a better chance of landing your first job as a DevOps engineer.

3 different high-level roadmaps models with different approaches to learning, the first two from the left follow the MVP-style, and the last one is linear.

  • The model on the left iterates horizontally in equal chunks over each area (good). It's simple and straightforward, each area (e.g., OS and code, containers and cloud, etc) has a fixed weight based on importance in the daily work. You don't need to think a lot about the next step, from the left to the right, you learn about each area and reach basic knowledge in all of them.

  • The model in the center iterates horizontally in dynamic chunks over each area (better). It's the same as the previous one but a bit more advanced, where it needs hands-on knowledge to decide the right weight for each area (based on many factors like targeted market or learner skills or background). This approach is more efficient; however, it requires guidance from an experienced DevOps engineer (e.g., a mentor or career coach) to define the weights correctly. It's even more critical when you have some sort of constraints like time or so (they are usually there in career shifts).

  • The model on the right iterates vertically over each area (bad). Don't do that! It has several drawbacks. For example, it delays your market fit, where in most cases, you cannot work as a DevOps engineer until you have completed all areas. Additionally, there is no space to review your learning approaches or holistic feedback in general. Finally, it's missing the connection between different areas, at the end of the day at work, you don't use a single skill at a time. I actually saw many disappointed people in the middle of the roadmap because they still didn't get the full picture.

So to ensure a more effective learning journey, it's recommended to adopt an MVP-style learning roadmap that allows for iterative learning across multiple areas while also considering the relevance and importance of each area in real-world DevOps work.

The Solution!

A dynamic MVP-style learning roadmap is one of the best ways to start as a DevOps engineer.

Let's put everything together. Based on my experience mentoring people in different stages (starting their first job, career shift, moving to another work style or company), I have found that the approach of using a dynamic MVP-style roadmap with hands-on projects designed by an experienced DevOps engineer has been highly successful. That means each project will cover all DevOps areas used in the job. It's also essential to understand the targeted market and organizations because, with different DevOps topologies, the DevOps engineer role requirements vary.

In conclusion, to start working DevOps engineer, you don't need to know "everything" about the software development life cycle (SDLC), nor start as Dev or Ops and then switch to DevOps. In many DevOps topologies, you can secure your first job as a DevOps engineer if you invest enough time in learning (not only the technical aspects) and follow an MVP-style roadmap. Also, undoubtedly having a senior DevOps on both ends (during the learning and in the company where you apply) will make your start much easier.

Continue Reading »


KubeconformValidator, my first Kustomize validator plugin - Golang


In the past, Kustomize suggested using transformers to validate resources, but later, it introduced validators, which are like transformers but read-only.

Say Hi to KubeconformValidator, a plugin built around Kubeconform to validate manifests schema within Kustonize ๐Ÿš€


  • Kubeval is not maintained anymore, and their repo suggests using Kubeconform as a replacement.
  • The KRM model is used in the plugin, so no more Kustomize legacy plugins.
  • During the weekend, I did it in 5 short iterations (in hours) to discover different options and structures.
  • In the past, I used kpt-functions-sdk/fn to work with KRM, but I decided to try Kustomize's kyaml/fn/framework, and it's great ๐Ÿ˜
  • The kyaml/fn/framework saved a lot of work with KRM and let met to just focus on the plugin logic. For example, I don't need to deal with OpenAPI Schema validation, it does it perfectly.


apiVersion: validators.kustomize.aabouzaid.com/v1alpha1
kind: KubeconformValidator
  name: validate
    config.kubernetes.io/function: |
      # Exec KRM functions.
       path: ../dist/kubeconformvalidator

      # # Containerized KRM functions.
      # container:
      #   image: aabouzaid/kubeconformvalidator
      #   network: true
  # Configure Kubeconform.
    output: json
    - AlertmanagerConfig
  # Also, direct Kubeconform args could be used
  # but "spec.args" has lower priority over "spec.config".
  # https://github.com/yannh/kubeconform#Usage
  # args:
  # - -output
  # - json
  # - -skip
  # - AlertmanagerConfig

That's it! Enjoy, and don't forget to take a look at awesome Kustomize list! :-)

Continue Reading »


Awesome Kustomize list - Kubernetes

After 3 years of using Kustomize intensively to manage Kubernetes manifests, I just created a list of "Awesome Kustomize" resources ๐Ÿคฉ️

If you are using Kubernetes, this repo will be a pretty good starting point for Kustomize plugins, guides, tips and tricks, and more.

Kustomize is not a new tool, it started in 2018, and now it's built into "kubectl" (since v1.14), which means it's now considered the official method to deal with advanced Kubernetes scenarios (e.g., GitOps).

If you are SysOps, DevOps, SRE, or anyone working intensively with Kubernetes, you definitely should read more about Kustomize!

Also, if you just use "kubectl" or Helm, then consider using Kustomize. It could help you in many different ways (it's not a replacement for Helm, you can use both).

Follow the repo to get the updates ๐Ÿš€️


Continue Reading »
Powered by Blogger.

Hello, my name is Ahmed AbouZaid and this is my "lite" technical blog!

I'm a passionate DevOps engineer, Cloud/Kubernetes specialist, Free/Open source geek, and an author.

I believe in self CI/CD (Continuous Improvements/Development), also that "the whole is greater than the sum of its parts".

DevOps transformation, automation, data, and metrics are my preferred areas. And I like to help both businesses and people to grow.

Latest Post

๐Ÿ”€Merger๐Ÿ”€, a schemaless strategic merge plugin - Kustomize

Kustomize is a great tool. I've been using Kustomize for almost 4 years and am happy with it. However, it's ...

Popular Posts

Blog Archive