As a Freelance Full-Stack Software Engineer and former CTO, I am passionate about building scalable platforms, distributed systems, and impactful user experiences. With a strong foundation in software engineering, AI, and leadership, I bridge business needs and technical execution across diverse industries—from insurance and telecom to real-time media and deeptech AI. I specialise in designing and managing high-performance systems, mobile and web applications, and machine learning pipelines. I thrive in fast-paced environments and enjoy mentoring cross-functional teams while driving product innovation from ideation to launch. Hard skills: NodeJS, Python, Flutter, JavaScript, AWS, GCP, AI/ML, Agile/Scrum and many more

Csongor Keller

PRO

As a Freelance Full-Stack Software Engineer and former CTO, I am passionate about building scalable platforms, distributed systems, and impactful user experiences. With a strong foundation in software engineering, AI, and leadership, I bridge business needs and technical execution across diverse industries—from insurance and telecom to real-time media and deeptech AI. I specialise in designing and managing high-performance systems, mobile and web applications, and machine learning pipelines. I thrive in fast-paced environments and enjoy mentoring cross-functional teams while driving product innovation from ideation to launch. Hard skills: NodeJS, Python, Flutter, JavaScript, AWS, GCP, AI/ML, Agile/Scrum and many more

Available to hire

As a Freelance Full-Stack Software Engineer and former CTO, I am passionate about building scalable platforms, distributed systems, and impactful user experiences. With a strong foundation in software engineering, AI, and leadership, I bridge business needs and technical execution across diverse industries—from insurance and telecom to real-time media and deeptech AI.

I specialise in designing and managing high-performance systems, mobile and web applications, and machine learning pipelines.
I thrive in fast-paced environments and enjoy mentoring cross-functional teams while driving product innovation from ideation to launch.

Hard skills: NodeJS, Python, Flutter, JavaScript, AWS, GCP, AI/ML, Agile/Scrum and many more

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Experience Level

Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
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Language

English
Fluent
Hungarian
Fluent
German
Intermediate

Work Experience

CTO at Syntric AI - Netherlands
December 31, 2023 - July 9, 2025
At Syntric AI, we generated 3D-based synthetic datasets to enhance the face recognition systems of our clients (border control, law enforcement, VR/AR). As the CTO, my responsibilities included developing a distributed data generation pipeline, synthesizing photorealistic facial expressions, hair, lighting, reflection changes, aging, and area-based mesh morphing variations among virtual humans to create diverse facial structures. Additionally training facial recognition AI models for data validation (VGG16 and AdaFace). Building a hyper-scalable infrastructure management pipeline with auto-scaling capabilities and custom alerting integrations. This system operated on cloud platforms such as AWS and GCP, managing over 50 GPU instances concurrently and dynamically adjusting resources to optimize cost-efficiency and rendering speed. Leading a cross-functional team of artists, software, and AI engineers, implementing agile processes. I built a product team from zero to four 3D artists, two
CTO at Octopus Visuals - Netherlands
December 31, 2021 - July 9, 2025
Octopus Visuals operated as a boutique web and mobile development agency with a core focus on enhancing the online presence of businesses struggling with limited visibility. As the CTO and lead developer my duties were: Frontend development in React and Flutter for web, Flutter native app development for Android and iOS, iOS native app development, Backend development in Laravel, NodeJS, and Python. Some of my projects: IPTV-EPG: IP-TV streaming native app for iOS and Android, XClass: Video-based learning native app for students in Ghana, HULI: Routing and navigation native app for cyclists in the UK, Dynalogic: Warehouse scanning native app for faster parcel deliveries, ItsCoastal: Luxury yacht and property rental platform in CA (app + web app) and many more.
Project manager, Scrum master at Angry Bytes / Ex Machina Group - Netherlands
December 31, 2019 - July 9, 2025
At Angry Bytes, we were building a live-streaming platform for TV channels and big corporates such as PWC and NatGeo. My daily activities covered a wide range of tasks such as leading an 11-member scrum team, made sure that we operated as data-driven as possible, leading native mobile (iOS and Android) and web app backend-frontend development, daily project management of multiple projects that have 2 million users worldwide, researching the best UX solutions and making sure the design and development teams are well briefed.
Mobile and webapp development manager at Generali Insurances - Hungary
December 31, 2019 - July 9, 2025
During my time at Generali, I led both the maintenance and development processes for customer-facing native apps and admin panels. My duties were: ensuring a high level of user-friendliness as output in the implementation of features for both native apps and customer-facing admin panels; focusing on customer needs while developing the online contract management system; overseeing the development of native applications; writing clear specifications for UX design and development teams, thoroughly testing and documenting any issues; actively participating in the planning of native apps and websites; contributing to the company's efforts in going more and more digital; maintaining the online analytical system and channeling insights back to the development.
Data scientist at Planet of the Apps mobile agency - Hungary
December 31, 2018 - July 9, 2025
I worked as a data scientist here, collaborating with partners in the telco and banking sectors. My primary responsibilities involved analyzing their data to uncover valuable insights and identify opportunities for enhancing their mobile applications. My daily tasks included leading data-driven development efforts for native Android and iOS apps, conducting data mining activities using the Count.ly mobile app analytics system, which involved writing queries and creating data visualizations to support my hypotheses, and strategizing for cross-platform development across various devices, including Android, iOS, AppleTV, AndroidBox, and Chromecast apps.

Education

Bachelors in Electrical Engineering at Obuda University - Budapest
January 1, 2016 - January 1, 2018

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Professional Services, Government, Education, Transportation & Logistics, Telecommunications, Financial Services, Media & Entertainment
    uniE621 Workforce management app used by 200.000+ users
    Managing user rosters for public sector employees, this app has become the 1 workforce solution in the Netherlands. Available on Android and iOS.
    uniE621 IPTV mobile app
    Flutter app — complete design and full development for Android and iOS.
    uniE621 GPS tracking app for creating a greener environment
    Picking up litter as you go — a great way to help clean nature while enjoying a beautiful walk in the Benelux. Available on Android and iOS.
    uniE621 GPS routing app for cyclists in the UK
    Create custom routes to discover hidden gems along your ride. Simply mount your device on your bike and enjoy the adventure. Available on Android and iOS.
    uniE621 Mindfulness app to get a fresh pair of eyes
    Need a Break is your go-to companion for breaking out of negative thought loops — offering small, thought-provoking challenges to shift your focus and reset your mind.
    uniE621 Mindfulness app to manage anxiety
    Stress, anxiety, and panic attacks can disrupt daily life — but you don’t have to face them alone. Rootd offers guided meditations and practical tools to help you stay calm and in control, right from your pocket. Available on Android and iOS.
    uniE621 Property management app
    A unique platform designed for co-living communities to share events, stay updated with news, and build their own social environment. Available on Android and iOS.
    uniE621 E-learning app for students and teachers
    Students can instantly enroll in classes, watch video materials, download articles, chat, post, share content, and more — all in one place. Tutors can upload videos, share learning materials, and answer student questions in real time. Available on Android and iOS.