About us.

Celeg Hannas is a consultancy focused on improvements in software quality.

Celeg Hannas was born from a realization that the testing approaches in practice did not fit in well with the fast-changing methodology of software development and the customers’ special needs. In 2010, Oliver Vilson founded Celeg Hannas to provide tailored software testing services to clients of all types and sizes.Our focus is mainly on testing web-based enterprise applications.Our vision is to be in a position where we have long-lasting partnerships with customers who can trust the quality of our work unconditionally.

Core philosophy

Team spirit - We understand and acknowledge that the synergy created by a team working together seamlessly is much more likely to give good results than individual efforts alone.

Competence - We strive to perfect our skills, both through constant self-learning and by regularly attending various events and trainings. We focus on learning something new every day. We challenge each other.

Drive - We are passionate about what we do. Testing is not just a job for us - it is our way of living and thinking. Testing is a state of mind.

Customer Satisfaction - Your success is our goal. As each customer is different we strive to find the settings and solutions that fit Your needs. We steer away from one-size-fits-all thinking because each software product is unique and should be treated accordingly.


Prove Expertise

Prove Expertise is considered to be one of the leading performance testing providers in Scandinavia. As a proof, they are the only company in Finland whose testers have won the "Finnish Tester of the Year" award twice.Combined with Celeg Hannas' expertise in Exploratory Testing, Test Analysis and Test Management we intend to offer more efficient testing service packages.


Codelight is web application development company located in Tartu. Their dedication to provide quality software development has created synergy between our companies


Helena Jeret-Mäe

Lead Consultant helena.jeret-mae@hannas.ee

Helena is the mastermind behind quality and process improvements, test management and strategy, team coaching, recruiting and many other topics. She loves to learn from people, improves what she can, and is passionate about outdoing herself every time.

Elo Eilonen

Lead Tester elo.eilonen@hannas.ee

Elo does hands-on testing in various software projects belonging to many different industries. She spends most of her time creating large scale modulated automated test setups to lessen the effort put into regression testing. She helps teams define their test automation needs, coverage and takes care of the implementation as well as training. A well worked out automation strategy enables human testers to focus on finding more complicated bugs.

Oliver Vilson

CTO oliver.vilson@hannas.ee

Oliver manages and spearheads testing projects, trains and coaches team members, consults customers in different Testing and QA topics and provides external training.

You seek quality...

...work with us and you shall find it. Together we can find a solution fitting your needs, so go ahead and get in touch.

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