Iwona Sarna Cloud Support Engineer II (Databases)

“I had the pleasure of working with Dariusz in AWS database team, and I can confidently say he is one of the most knowledgeable and dedicated professionals I’ve met. Holding all AWS certifications, Dariusz brings an exceptional depth of expertise across the entire AWS ecosystem. He consistently stood out as a top resolver and best performer, always going above and beyond to deliver high-quality solutions for even the most complex challenges. His technical knowledge is truly outstanding, but what makes him even more remarkable is his professionalism, reliability, and willingness to share his expertise with others. Dariusz sets the standard for quality and excellence in every task he takes on. I would highly recommend him to any team or organization looking for someone with world-class AWS expertise and a proven track record of success.”

Kennedy Marques Cloud Support Engineer I - Databases

“Dariusz is one outstanding professional/engineer. I worked closely with Dariusz for over a year. He joined AWS as Level 1 Engineer. I had the pleasure to see him progressing as L2 engineer and I can say it was well deserved! He managed to achieve all available AWS certifications! That is a huge accomplishment! He won numerous AWS too. Dariusz is a live ecyclopedia! Extremely focused and an essencial asset to our team. The team would not be the same without him. He is a all around/complete engineer. I would not hesitate to recommend Dariusz to any role that requires MySQL, DMS, Networking, DevOPS, Linux, SQL Server, Lambda or pretty much most of the services we offer at AWS.”

Kübra Doğmuş System Engineer

“Working alongside Dariusz has been an incredibly rewarding experience, and I can confidently say he is among the finest engineers I've ever had the privilege to collaborate with. Dariusz's passion for his craft is not only inspiring but also uplifting. His exceptional ability to teach and mentor others sets him apart, creating an environment where everyone can thrive. I have gained invaluable knowledge from him, and I deeply appreciate the insights and guidance he has generously shared. I am excited to see the remarkable achievements that lie ahead for Dariusz. Thank you, Dariusz, for your outstanding contributions and for being such a positive influence in AWS!”

Arvind Tewatia Cloud Engineer Database

“I highly recommend Dariusz. I've had the pleasure of working alongside them at Amazon Web Services (AWS), where he have consistently provided me with invaluable expertise in cloud, network, and database technologies. Dariusz possesses a deep and robust knowledge of highly technical concepts and has an exceptional talent for explaining them clearly and effectively. Whenever I've faced a challenging problem, he have been generous with their time and insightful with their solutions. He has been a great trainer as well and has a tremendous asset to any team and one of the most knowledgeable professionals I've had the opportunity to learn from.”

Zohaib Qaiser Systems Development Engineer

“I had the pleasure of working with Darius on the AWS Database team, and he was an outstanding colleague. He’s sharp, reliable, and always ready to dive into complex problems without hesitation. Beyond his technical skills, Darius is a great team player, supportive, easy to work with, and genuinely committed to getting things done right.”

Dr. Fernando Perez Tellez Computing Lecturer & Researcher

“Dariusz is a passionate in the ICT area with lots of experience in several technologies. He is always finding the way of knowing more and sharing his experience.”

Krystian Kunowski Technical Support Engineer 2

“I had the pleasure of working with Dariusz Terefenko at Amazon Web Services, where we were in different divisions but had multiple opportunities to collaborate across teams. Each time we worked together, Dariusz impressed me with his deep technical expertise, strong communication skills, and his ability to solve complex problems under pressure. He consistently demonstrated a proactive and customer-focused mindset, which is critical in cloud roles. Whether it was troubleshooting high-impact issues, sharing knowledge, or driving improvements across processes, Dariusz always delivered with precision and professionalism. Beyond his technical strengths, Dariusz is a great teammate reliable, helpful, and easy to work with. He brings a great attitude to any project and is highly respected by colleagues across the organization. I’m confident that any company hiring Dariusz for a cloud-related role will gain not just a skilled engineer, but a trusted partner and valuable asset to their team.”

Sergio Manuel Molina Perez Senior Site Reliability Engineer

“A few years ago I had the chance to work with Dariusz when we were both Cloud Support Engineers at AWS, in the databases team. He's incredibly strong technically — earning all the AWS certifications (yes, even the golden jacket!) — but what really stands out is how well he explains things and helps others grow. He’s a great teammate, focused, hardworking, and always willing to jump in and solve problems. Anyone would be lucky to add his skill set and tech knowledge to their team!”

Ankush Madha IT Operations Analyst @Alchemy Global Solutions

“Dariusz is one of the most knowledgable person I have worked with, a SME of his field. He is very organized and super efficient at meeting his delivery timelines and has a knack for future requirements insight.”

Pavol Pazitka Global Finance Operations | Global Payroll @Grant Thornton

"I would 100% recommend Dariusz to anyone who is looking to expand their team with a highly-skilled, educated, and experienced professional. He is reliable, responsible, motivated, and target orientated. Dariusz was always a helpful team player, with leadership skills who would take the extra mile to achieve team goals in addition he can work well on his own as well. In my opinion, Dariusz is also a “long-life learner” who is constantly upgrading his skills to keep up with the competitive market.”

Julian Alwandy DevOps | Blockchain @Crypto.com

“Dariusz was always fulfilling my expectation with explaining what we need and why we need it, allowing us to plan things ahead sprint wise and help with the growth of the business. Dariusz is a talented person, he always thrived and delivered what I expected out of him. A highly recommended hire. Though I recommend to put Dariusz in a challenging environment rather than just ad hoc as you'll be able to bring more out of him.”

Ning Ng Senior Solution Consultant @Microware Limited

“Dariusz is one of the most knowledgeable and skillful IT engineers I have ever met. I have witnessed his impressive abilities in solving difficult IT infrastructure problems and delivering top-notch work, from hands-on implementation to documentation. With an intrinsic motivation in pursuing the best, I have been positively influenced by his strong work ethic and immense passion in learning new technology, even in his free time–"the pursuit of knowledge for its own sake,". Despite his impressive technical expertise, Dariusz is a kind-hearted human being who genuinely cares about the well-being of his teammates.”

Paul McInerney Operations Director @Enterprise Imaging Systems Ltd

“Dariusz displayed a constant ambition to learn new technologies to benefit the company, primarily focused on Cloud Certifications for Azure / AWS / Google. Dariusz has strong determination to resolve issues in the best way possible and document the results which added a lot of benefit to his colleagues and new hires.”

David White Lecturer in Computing @Technological University Dublin

“Dariusz has an excellent combination of both the hard skills; deep understanding of the technologies (complex hands-on lab deployments and the soft-skills; an ability to clearly communicate these ideas (evaluate, synthesis & troubleshoot).”

Thomas Whelehan Implementation Consultant @Enterprise Imaging Systems Ltd

“Dariusz is never shy in sharing this knowledge with me and has helped my improve my knowledge drastically. Dariusz is an incredibly approachable person on all matters not just technical queries. He is very good with customers and has great relationship with them and also other members on the team. Along with this Dariusz is a very hard working individual and with this quality was able to manage and finish multiple projects. His skills in SQL and cloud computing are crucial to getting these projects done.”

Eoin Melly Software Development Team Leader @Enterprise Imaging Systems Ltd

“Key skills and talents that Dariusz holds include his attention to detail, his willingness to learn and improve his (already advanced) expertise in his field, his team leading abilities and first and foremost his willingness to work hard on and solve difficult problems. Dariusz’s natural industrious nature was essential to get multiple projects over the line, and he is always willing to help out a fellow colleague who may be struggling with an issue.”

Fabio Benko Project Lead Developer @Zurich Insurance

“Really high skills in Sql Database, Windows Server Administration and Security, team work and proactive.”

Orla Cafferty Chief Executive Officer @Datascan Redaction Services

“Dariusz developed and implemented internal processes for the successful processing of all such data. In addition to management of the Document Services Team, Dariusz was responsible for the company’s IT infrastructure, and provided first point of contact to our external monitoring providers. At all times, Dariusz was dedicated and interested in his role at Datascan, he has a love of process and procedure, and his ability to take a project from inception to conclusion means that he would be a very welcome addition to any organisation seeking a dedicated and organised professional.”

Padraic D. Cafferty Executive Chairman @Datascan

“He was totally focussed on delivering the ultimate solutions across a broad spectrum of advanced communication and storage systems and platforms where such qualities and skills are required.”

George Eager Property & Retail Partnership Manager @Tesco Ireland

“I have always found him to be professional, courteous, extremely diligent and hard working. Dariusz strengths are his organisational skills and his ability to multi task. His relentless drive to achieve perfection is admirable and he certainly does not lack energy, drive or enthusiasm.”