Mantas Stangvila

Apr. 2021 - Present Current

Pizza Hut Digital Ventures

Tech stack: Node.JS, C#, TypeScript, React, Redux, Redux Sagas, Kubernetes, AWS (SQS, SNS, DynamoDB, ECS, CloudFront, Lambda), Kubernetes, CircleCI, PostgreSQL, NestJS, JavaScript, NextJS, Redis, Tailwind CSS.

Led the development of a scalable restaurant data management microservice, enhancing platform efficiency and standardization across all Pizza Hut restaurants.

Uncovered and alerted management to a critical timing attack vulnerability, an exploit that could have enabled unauthorized free orders, safeguarding the company's revenue integrity.

Dramatically reduced fraud/chargeback rate, saving £15,000 monthly, by integrating 3D Security into the Google Pay system.

Automated and streamlined the update process for payment provider credentials, reducing error rates and potential downtime.

Enhanced customer engagement by integrating "Trivial Pursuit" lottery campaign into marketing emails.

Worked on a contactless delivery project improving Pizza Hut's delivery platform.

Played a key role in enhancing the contactless delivery system, improving customer service and operational efficiency.

Contributed to the successful integration of the "Qwikcilver" gift card platform, ensuring seamless API functionality and stakeholder communication.

Enhanced security and maintainability by migrating the HiPay payment provider to AWS Secrets Manager.

Feb. 2020 - Apr. 2021 1 year 2 months

HeadBox Solutions Ltd

Tech Stack: TypeScript, Node.js, React.js, AWS Lambda (Serverless), AWS SNS, AWS SQS, AWS S3, PostgreSQL, Docker, Argo CD.

Addressed a severe security flaw in the PostgreSQL database, preventing a potential exploit that could have erased all stored data.

Reduced manual account manager intervention by 31% through automating event organization processes using AWS Lambda.

Led the development and launch of two new projects, modernizing business management tools and user interfaces.

Trained and aided developers, occasionaly lead standups.

Optimized developer workflow, cutting project compilation time from 89 seconds to 0.5 seconds, significantly boosting productivity.

Directed the implementation of AWS SNS and SQS services to establish a robust message architecture for efficient communication between microservices.

Expanded and improved the AWS S3 document storage solution, adding robustness and scalability to the feature set.

Dec. 2018 - Jun. 2019 6 months

Vilnius IT Solutions, UAB

Tech stack: Node.JS, TypeScript, React, MobX, PostgreSQL, REST API, Redis.

Saved over 100,000 EUR by identifying and fixing a major bug in the giveaway system

Boosted website traffic by 20% through a complete overhaul of the affiliate system, enhancing both front-end and back-end.

Developed a peer-to-peer exchange system, achieving a drastic increase in platform liquidity.

Improved user experience by resolving front-end responsiveness issues, leading to better customer satisfaction.

Created and implemented new REST API endpoints to support website redesign and functionality enhancements.

2016 Mar. - 2018 Jan. 2 years

SkinHouse.lt

Tech stack: Node.js, React, MobX, WebSockets, PostgreSQL, RabbitMQ.

Founded and scaled a middleman service for Steam platform items, achieving over 50,000 users and 100+ daily transactions.

Architected and implemented a high-performance back-end in Node.js, achieving a rapid 0.10 seconds response time for user requests.

Developed a responsive and efficient front-end using React and MobX, achieving a 95% Google Pagespeed score.

Automated the trading of goods with bots, ensuring offers reached users within 0.5 seconds.

Implemented a convenient and diverse selection of payment gateways integrations for users: BitPay (Bitcoins), PaySera, Stripe, PayPal.

Engineered a custom CMS for user monitoring and management, streamlining administrative processes.

Sep. 2017 - Jun. 2018 9 months

CSGOSick.com

Tech Stack: React, Node.js, PostgreSQL, RabbitMQ, WebSockets.

Designed and developed a robust online casino back-end, attracting over 265,000 users and ensuring a stable daily profit.

Programmed backend systems for jackpot and coinflip games, affiliate programs, and giveaways.

Achieved system scalability and reliability, handling 250 requests per second with sub-0.15 second response times.

Built multi-purpose microservice for automating unreliable Steam platform trading system resulting in 20% fewer user complaints.

Implemented a blockchain-based provably-fair system in games, gaining user trust and increasing website traffic by 10%.

Automated deployment processes, reducing errors and downtime during software updates.

Jan. 2017 - Sep. 2017 8 months

Gambling Project - Hercus

Tech Stack: Node.js, PostgreSQL, WebSockets (Socket.io).

Developed a unique, real-time Titan gambling game-mode utilizing WebSockets for live player interactions.

Engineered a scalable architecture for both the front-end and back-end.

Designed a high-performance PostgreSQL database structure, achieving an average query response time of just 0.05 seconds.

2015 - 2016 1 year

CSGOMythos.com

Tech stack: JavaScript, WebSockets, jQuery, Node.js, PostgreSQL, HTML, CSS.

Architected and developed an engaging gaming platform, including levels, dice, roulette, and crash games.

Designed a comprehensive game and user management system, including a custom authentication system for Node.js.

Portfolio can be seen at https://FindMantas.dev

2014 - 2015 1 year

CSGOManiac.com

Tech Stack: JavaScript, WebSockets, jQuery, PHP, Node.js, MySQL.

Developed a pioneering Steam platform-based jackpot gambling website, the first of its kind, blending various technologies for a seamless user experience.

2014 - Present 10 years

Other

Developed game modifications through reverse engineering and assembly-level analysis, gaining deep understanding of low-level system architecture.

Built an operating system to explore low-level computer architecture implementing CPU instruction sets and memory management concepts.

Successfully identified and reported critical security vulnerabilities in major platforms including CSGOWild.com, CSGOLotto.com, and CSGOFast.com, earning bounties for bug hunting.

Managed a diverse cryptocurrency mining operation, including Bitcoin, Bitcoin Cash, and Litecoin.