MongoDB Certified Professional Spotlight: Konstantin Manchev

Eloise Giegerich


For this week’s spotlight we’re chatting with Konstantin Manchev, a DBA- and DEV-certified professional who works as a MongoDB Database Administrator at the European Patent Office out of the Netherlands. Konstantin has worked on several interesting telecom data analysis projects throughout his career; below, he shares how his MongoDB certification gave him the flexibility and freedom to grow these projects, and the confidence to approach future endeavors.

Eloise Giegerich: Hi, Konstantin! Thanks for taking the time to speak with me today. Let’s begin by diving into your tech background. When did you first become interested in tech, and where do you currently work?

Konstantin Manchev: My tech career started back in 2001 when I began working as a telecom support engineer at Mobiltel, the first Bulgarian mobile operator, which is now part of the Telecom Austria Group. With a strong focus on data analysis and automation, my time at Mobiltel allowed me to successfully contribute to different automation and development projects using the latest market technologies in the area.

I am currently working as a MongoDB DBA in the European Patent Office (EPO). It’s an exciting place to work because we face new and multiple administration and development challenges every day, including backups, restoration, upgrades, housekeeping, and performance optimization for huge databases.

EG: How did you first discover MongoDB? Can you share any projects you’ve worked on with the database?

KM: In 2010 I was assigned to automate a telecom data analysis project; this involved collecting all prepaid systems event logs from an online charging system and identifying incorrectly charged subscribers, as well as generating statistics for specific charges per minute in real time. It was through this that I had the opportunity to test and compare suitable database storage systems that would best fit my and my team’s needs. I did some research and experimenting, and discovered the many advantages offered by MongoDB. To meet the requirements of specific use cases, some databases just took too much time and effort, or made tasks impossible to complete all together; with MongoDB, I could get the job done easily and efficiently.

MongoDB attracted me with its schemaless structure, easy scalability and deployment, availability across the majority of operating systems, clear documentation, customizable performance/reliability, and free of charge training courses. The database allowed me to focus more singularly on my application development, as I no longer needed to worry about scalability and high availability – functions that are expected by default in any real-time telecom application use case.

In late 2014, I started working at Cisco Systems, supporting one of the best mobile packet core policy applications on the market at that time, CPS (Cisco Policy Suite, formerly QPS – Quantum Policy Suite), which used MongoDB as a backend. Troubleshooting customer problems in real time with MongoDB allowed me to gain invaluable hands-on experience with the product, which is what first got me interested in pursuing certification.

In addition to working with the database itself, MongoDB’s community support has really helped my team advance our projects. At the moment, we are facing issues switching to the new storage engine, WiredTiger, which has some big advantages over mmapv1 (such as compression and document level concurrency control), but also smaller drawbacks. For example, it is currently impossible in WiredTiger to run offline database folder backups inside dbPath. As we face these drawbacks, we are happy and grateful to work with the MongoDB support team in Dublin, as they are very responsive, and always helping us with ongoing queries.

EG: What other databases have you worked with, and how does MongoDB compare?

KM: I have developed a few projects for specific telecom applications using MySQL, Postgres, and Oracle. But, as I mentioned earlier, what I like about MongoDB is the freedom it gives developers and the built-in scaling possibilities, like sharding and replication. These latter capabilities really helped me when I was developing my SMS Center events parsing, collection, and analysis project (mentioned above). Another project I worked on with MongoDB involved parsing a daily snapshot of prepaid mobile subscriber profiles, collecting and analyzing the data, and tracking changes in identification and problem analyses.

EG: You mentioned troubleshooting with MongoDB as a catalyst for your interest in certification. Was there anything else that inspired you to become certified?

KM: It was mainly that troubleshooting experience; after having significant exposure to different sizes and types of MongoDB deployments, I decided to improve my skills and try learning the technology in-depth. The way to prove that I had improved my skills and mastered the technology was to see that acknowledgement through MongoDB’s DBA and DEV certification exams.

EG: Which MongoDB University courses did you take?

KM: To prepare, I took: M310: MongoDB Security, M101J: MongoDB for Java Developers, M123: Getting Started with MongoDB Atlas, M101P: MongoDB for Developers, M202: MongoDB Advanced Deployment and Operations, and M102: MongoDB for DBAs. All the trainings were very helpful and offered great practical exercises to strengthen my confidence in the material.

EG: Since becoming certified, have you experienced any benefits, personal or professional?

KM: Personally, I now feel more confident in my skills having been DBA- and DEV-certified. Professionally, these skills are officially recognized with the certification title, which makes me a much more competitive player in job markets across the world!

EG: How have you applied, or how can you apply your certification skills to future projects?

KM: MongoDB allows you to focus on a specific project task, removing the whole complex SQL abstraction data access layer that exists in relational databases. With my certification knowledge, I’ve been able to easily use MongoDB as a backend, which makes projects move along much faster than they would’ve with a SQL system.

EG: Can you offer any advice or tips to those about to take, or retaking, their exam(s)?

KM: The good thing about MongoDB is that you don't need expensive hardware to learn. You can install your test (practice) sharded clusters in any test virtual machine of your choice and break, fix, and simulate any kind of activity. To get a hands-on experience with the database, try creating from scratch; simulate any kind of errors and try to fix them. By doing this, you will learn how MongoDB behaves in different situations and gain valuable preparation for the exams. Of course, if during the troubleshooting process you face any issues, you can always check the online documentation and forums for fresh ideas.

EG: And finally, what advice or encouragement do you have for those considering pursuing certification?

KM: It will be difficult, but be brave, face the challenges, and never give up following your dreams!

Thanks again to Konstantin for taking the time to share his story! If you’re interested in getting professionally certified, you can Learn more about the MongoDB certification process. If you’re already certified and would like to be featured in a blog post, let us know at