Robert Lehmann, Developer in Berlin, Germany
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Robert Lehmann

Verified Expert  in Engineering

Full-stack and Unity3D Game Developer

Location
Berlin, Germany
Toptal Member Since
September 13, 2022

Robert is a passionate gamer, experienced director of engineering, and blockchain enthusiast with 10+ years of professional experience and a bachelor's degree in game design. He has developed two multimillion-dollar-grossing games in Unity3D, published on Google Play and the App Store: Solitaire Showtime and Mahjong City Tours, which has over 25 million downloads. Robert has also developed unique smart contracts and dApps across different blockchains.

Availability

Part-time

Preferred Environment

Unity, React, Amazon Web Services (AWS), Gaming, Unity3D, Virtual Reality (VR), Unity SDK, Technical Design, Technical Architecture, Payment APIs, CTO, Full-stack, Firebase, Mobile Development, Analytics, Google Analytics, Python, C#, .NET, Bots, Discord Bots, Telegram Bots, AWS Lambda, WebGL, MMORPGs, Serverless, Back-end, Source Code Review, Code Review, AWS Cloud Architecture, 3D Games, C++, Games, Amazon DynamoDB, Amazon S3 (AWS S3), Web Security, Web Scraping, Unity2D, Mobile Games, Unity3D Native Plugin Interface, JSON, DevOps, Mobile Apps, 2D, WebView, User Authentication, Cryptocurrency Wallets, MetaMask, Blockchain, API Integration, Integration, C#.NET, Lambda Functions, Game Development, Gameplay Development, Mobile App Development, Google Play Store, Non-fungible Tokens (NFT), Smart Contracts, RPG, Gamification, Mathematics, Cross-platform App Development, Vercel, Rust, Crypto, Apache Kafka, OpenAI GPT-3 API, OpenAI GPT-4 API, OpenAI, ChatGPT, Character Rigging

The most amazing...

...thing I've developed is Mahjong City Tours, a mobile game with over 25 million downloads on Google Play and the App Store.

Work Experience

Associate Director, Engineering

2016 - 2022
Jam City
  • Built client applications for Mahjong City Tours and Solitaire Showtime in Unity3D, including native-level requirements, such as ads and mobile notifications.
  • Developed the back end for Mahjong City Tours and Solitaire Showtime as a serverless application within AWS (Lambdas, DynamoDB, etc.) combined with other services like Firebase.
  • Set up the overall pipeline for the Berlin Studio, including automated client builds per merged Git patch sets with distributions to test users and a simple interface for engineers to deploy personal back ends using AWS CloudFormation.
  • Identified and fixed memory leaks across the front end and back end (Node.js) to decrease user-facing issues and reduce the overall costs of services.
  • Developed an in-house solution for LiveOps, including an easy-to-use interface for the PM and handy ways for artists to deploy on-demand assets into the LiveOps pipeline for later use, such as offers.
  • Built analytical tracking mechanisms and dashboards to analyze the overall performance of any product using Databricks and SQL.
  • Implemented 3D Secure 2.0 authentication for MasterCard to increase the security of online transactions and comply with industry standards.
  • Oversaw a split system where the client (mobile app) was doing transactions. Fetched the challenge data per HTTPS request and sent it to our back end for further validation, where we checked it with the 3D secure vendor data.
  • Implemented various Visa APIs like Visa Payments Processing APIs to enable direct credit card payments for both mobile and web applications.
  • Demonstrated hands-on experience with character rigging, encompassing the creation and optimization of character skeletons, setting up inverse kinematics, and ensuring the seamless movement of 3D models.
Technologies: C#, JavaScript, Unity, CI/CD Pipelines, Amazon Web Services (AWS), SaaS, Architecture, SQL, Photon, Gaming, Unity3D, Virtual Reality (VR), .NET Core, Azure, iOS, Android, HTML, CSS, Node.js, MongoDB, APIs, Swagger, User Interface (UI), Unity SDK, Technical Design, Technical Architecture, React, Figma, CTO, Full-stack, Firebase, TypeScript, Swift, Mobile Development, Objective-C, Analytics, Google Analytics, Heatmaps, NoSQL, Database Design, Databases, .NET, Front-end, Next.js, Bots, Discord Bots, Telegram Bots, Memory Leaks, Proof of Concept (POC), AWS Lambda, Webhooks, WebGL, MMORPGs, Networking, Serverless, Back-end, OAuth 2, OAuth, Security, Source Code Review, Code Review, Project Consultancy, PHP, MySQL, AWS Cloud Architecture, Augmented Reality (AR), ARKit, LiDAR, Back-end Architecture, ASP.NET MVC, 3D Games, C++, Games, Amazon DynamoDB, Amazon S3 (AWS S3), Web Security, Web Scraping, Unity2D, Mobile Games, Unity3D Native Plugin Interface, JSON, Zapier, Python, DevOps, Data Visualization, Charts, Interactive Maps, Interactive UI, Remix IDE, Firebase Realtime Database, Mobile Apps, React Native, Scrum, Payment Gateways, Express.js, Sass, Live Chat, 2D, Mobile, WebView, Progressive Web Applications (PWA), User Authentication, REST, Amazon RDS, AWS Elastic Beanstalk, Amazon CloudFront CDN, jQuery, Headless Software, Virtual DOM, Cryptocurrency Wallets, MetaMask, Blockchain, API Integration, Integration, Leadership, SQL Anywhere, SAP, C#.NET, Team Leadership, Lambda Functions, Exports, MERN Stack, Technical Leadership, Mobile Game Development, Software Architecture, REST APIs, Cron, CSV, Company Databases, Calendars, Smart Homes, Amazon Alexa, Google Assistant, Google Calendar API, Smart Devices, MUI (Material UI), Kotlin, Unreal Development Kit (UDK), Unreal Engine, Unreal Engine 4, Unreal Engine 5, Game Development, Gameplay Development, Decision Trees, Twilio API, Lottie, HTML5, GraphQL, AWS Amplify, Amazon Cognito, Flutter, NestJS, DataRobot, Snowflake, PostgreSQL, Machine Learning, Artificial Intelligence (AI), Cross-platform, Internet of Things (IoT), Responsive Web Apps, Adaptive Design, Web Design, SSL Certificates, Cloud Firestore, Angular, Ethereum, Google Cloud, BigQuery, Mobile App Development, Microsoft Excel, Spreadsheets, Apple Numbers, Multiplayer, Microsoft Visual Studio, Web Development, Design, WebRTC, Ruby on Rails (RoR), Discord, Desktop App Development, Windows Desktop Software, Android SDK, Java, Model View Viewmodel (MVVM), Gradle, Google Play Store, Non-fungible Tokens (NFT), Smart Contracts, Data Analysis, Web 3.0, GitHub, Firebase Cloud Functions, Front-end Development, ASP.NET, ASP.NET Core, Reverse Engineering, Software Design, Scalable Architecture, PixiJS, Back-end Development, 3D Rendering, 3D, Django, Groovy, Responsive Layout, Grails, Amazon EC2, Redis Cache, WebSockets, Amazon CloudWatch, AWS IoT, .NET MAUI, Blueprint, RPG, Mobile UX, Object-relational Mapping (ORM), iOS SDK, Mobile App Design, Git, Responsive Web Design (RWD), User Experience (UX), Cryptocurrency, Laravel, SDKs, Xbox, PlayStation, Windows, Tailwind CSS, Dart, Axios, OpenAPI, Redux, Postman, Application Engineering, Vue, Gamification, XML, Card Payments, 3D Secure, 3D Secure 2.0, Authentication, Near-field Communication (NFC), Bluetooth LE, Secure Storage, Joomla, IIS SQL Server, Visual Basic, Azure SQL Databases, Mathematics, C++/CX, Chrome Extensions, Casino Games, ECMAScript (ES6), Generative Pre-trained Transformers (GPT), Natural Language Processing (NLP), GPT, Natural Language Understanding (NLU), Dialogflow, Cross-platform App Development, UI Components, Jest, Single Sign-on (SSO), D3.js, Social APIs, Graph Databases, Amazon Neptune, Web UI, Chatbots, Accessibility, Location Services, Mobile Architecture, Audio, Video Streaming, Data Architecture, Data Integration, Microservices, Cloud Architecture, Amazon API Gateway, AWS IAM, Amazon SageMaker, Amazon Simple Queue Service (SQS), Mobile Game Design, Android Game Development, Chart.js, Google Cloud Platform (GCP), Crypto, Plaid, Plaid API, Jira, Confluence, Algorithms, Twitter API, Database Architecture, Agile, Data Structures, Agile Software Development, Online Payments, Web Platforms, Elasticsearch, MEAN Stack, Azure SQL, Azure Functions, Unit Testing, Apollo, SVG, Bootstrap, Amazon ElastiCache, AWS Simple Notification Service (SNS), gRPC, Azure Data Lake, Azure Queue, AWS Fargate, Data Engineering, ETL, PlayFab, Unity Game Assets, Photon Unity Networking (PUN), In-app Purchases, Cloud, Microsoft, Minimum Viable Product (MVP), Early-stage Startups, Game AI, Slack App, Slackbot, Docker, Svelte, AWS CloudFormation, Amazon Cognito User Pools, AWS AppSync, Google Sheets, Test-driven Development (TDD), Full-stack Development, LangChain, Server Security, Shopify API, Redis, AppSheet, Data Analytics, 360° Video, Photogrammetry, State Machines, Character Animation, Puppet, Oculus, VR Interfaces, QA Testing, OpenAI, ChatGPT, Video Gaming, Autodesk FBX SDK, Maya, Character Rigging

Mahjong City Tours

https://www.jamcity.com/game/mahjong-city-tours/
A multimillion-dollar-grossing game on Google Play and the App Store. As the director of engineering, I led a capable team of several engineers and personally developed most of the client, back end, and related pipelines for the project.

Solitaire Showtime

https://www.jamcity.com/game/solitaire-showtime/
A multimillion-dollar-grossing game on Google Play and the App Store. As the director of engineering, I led a capable team of several engineers and personally developed most of the client, back end, and related pipelines for the project.

Equity Token

https://equitytoken.finance/
Equity is a decentralized finance project that provides passive income and storing value while being peer-to-peer (P2P) payment friendly.

The Equity dashboard provides easy, user-friendly options to review or change contract-related data based on the connected wallet.

Vault

https://www.vault.technology/
Vault is a service that lets users easily and securely deposit their tokens within a special smart contract. There is an option to add multi-user authentication, and withdrawals are free. Developers can securely utilize it to manage liquidity pools and move them to different pairs without releasing them from a secure endpoint.

Languages

C#, JavaScript, SQL, HTML, CSS, TypeScript, Swift, Python, C#.NET, Kotlin, HTML5, Java, Groovy, RPG, XML, ECMAScript (ES6), Objective-C, PHP, C++, Sass, GraphQL, Snowflake, Dart, Visual Basic, C++/CX, Solidity, Rust

Frameworks

Unity, Unity3D, .NET Core, .NET, Next.js, ASP.NET MVC, Unity2D, React Native, Express.js, MUI (Material UI), Flutter, NestJS, Angular, Android SDK, ASP.NET, ASP.NET Core, PixiJS, iOS SDK, Photon Unity Networking (PUN), Photon, Swagger, OAuth 2, ARKit, Unreal Engine, Unreal Engine 4, Django, Grails, Blueprint, Laravel, Tailwind CSS, Redux, Jest, gRPC, Ruby on Rails (RoR), Bootstrap, Svelte

Libraries/APIs

React, Node.js, WebGL, REST APIs, Google Calendar API, AWS Amplify, D3.js, Social APIs, Exchange API, jQuery, Twilio API, WebRTC, Web3.js, Binance API, OpenAPI, Vue, Chart.js, Plaid API, Twitter API, Shopify API

Tools

Unity SDK, Figma, Google Analytics, WebView, Amazon CloudFront CDN, MetaMask, Cron, Amazon Cognito, Microsoft Excel, Spreadsheets, Microsoft Visual Studio, Gradle, GitHub, Amazon CloudWatch, Git, AWS IAM, Amazon Simple Queue Service (SQS), Jira, Confluence, Amazon ElastiCache, AWS Simple Notification Service (SNS), AWS Fargate, PlayFab, AWS CloudFormation, Google Sheets, Remix IDE, Google Assistant, Unreal Development Kit (UDK), DataRobot, BigQuery, Postman, Dialogflow, Amazon SageMaker, Plaid, AWS AppSync, Puppet, Zapier, Autodesk FBX SDK, Maya

Paradigms

Serverless Architecture, Mobile Development, Database Design, Back-end Architecture, DevOps, Scrum, REST, Cross-platform, Model View Viewmodel (MVVM), Responsive Layout, Object-relational Mapping (ORM), Mobile App Design, Gamification, Microservices, Mobile Game Design, Agile, Agile Software Development, Test-driven Development (TDD), Desktop App Development, Responsive Web Design (RWD), MEAN Stack, Unit Testing, ETL

Platforms

Amazon Web Services (AWS), Azure, iOS, Android, Firebase, AWS Lambda, Mobile, Blockchain, Ethereum, Amazon EC2, Windows, Google Cloud Platform (GCP), Azure Functions, Microsoft, AWS Elastic Beanstalk, Amazon Alexa, AWS IoT, Xbox, PlayStation, Bluetooth LE, Joomla, Docker, Oculus, Apache Kafka

Storage

MongoDB, NoSQL, Databases, MySQL, Amazon DynamoDB, Amazon S3 (AWS S3), JSON, PostgreSQL, Cloud Firestore, Redis Cache, Azure SQL Databases, Graph Databases, Database Architecture, Azure SQL, Azure Queue, Redis, Firebase Realtime Database, Company Databases, Google Cloud, IIS SQL Server, Data Integration, Elasticsearch, SQL Anywhere

Industry Expertise

Security, Web Design

Other

Programming, Game Design, Computer Science, CI/CD Pipelines, Architecture, Gaming, APIs, User Interface (UI), Technical Design, Technical Architecture, Full-stack, Analytics, Front-end, Memory Leaks, Proof of Concept (POC), Serverless, Back-end, Source Code Review, Code Review, Project Consultancy, AWS Cloud Architecture, AWS Certified Developer, 3D Games, Games, Web Security, Mobile Games, Unity3D Native Plugin Interface, Data Visualization, Interactive UI, Mobile Apps, 2D, User Authentication, Amazon RDS, Headless Software, Virtual DOM, Cryptocurrency Wallets, API Integration, Integration, Leadership, Team Leadership, Lambda Functions, Exports, MERN Stack, Technical Leadership, Mobile Game Development, Software Architecture, CSV, Calendars, Smart Homes, Smart Devices, Game Development, Gameplay Development, Adaptive Design, Mobile App Development, Apple Numbers, Web Development, Design, Discord, Google Play Store, Smart Contracts, Ethereum Smart Contracts, Firebase Cloud Functions, Front-end Development, Reverse Engineering, Software Design, Scalable Architecture, Back-end Development, 3D Rendering, 3D, .NET MAUI, Mobile UX, User Experience (UX), SDKs, Application Engineering, Authentication, Cryptography, Decentralized Applications, Mathematics, Casino Games, Cross-platform App Development, UI Components, Single Sign-on (SSO), Amazon Neptune, Web UI, Chatbots, Mobile Architecture, Data Architecture, Cloud Architecture, Amazon API Gateway, Android Game Development, Crypto, Algorithms, Data Structures, Trading, Azure Data Lake, Data Engineering, Unity Game Assets, In-app Purchases, Cloud, Minimum Viable Product (MVP), Early-stage Startups, Game AI, Slack App, Slackbot, Amazon Cognito User Pools, Full-stack Development, AppSheet, State Machines, Character Animation, Video Gaming, Scalability, IT Infrastructure, SaaS, Virtual Reality (VR), CTO, Heatmaps, Bots, Discord Bots, Telegram Bots, Webhooks, MMORPGs, Networking, OAuth, Augmented Reality (AR), LiDAR, Web Scraping, Charts, Interactive Maps, Payment Gateways, Live Chat, Progressive Web Applications (PWA), Unreal Engine 5, Decision Trees, Lottie, Machine Learning, Artificial Intelligence (AI), Internet of Things (IoT), Responsive Web Apps, SSL Certificates, Multiplayer, Windows Desktop Software, Non-fungible Tokens (NFT), Data Analysis, Web 3.0, Tokenomics, WebSockets, Cryptocurrency, Axios, Card Payments, 3D Secure, 3D Secure 2.0, Near-field Communication (NFC), Secure Storage, Chrome Extensions, Natural Language Processing (NLP), Natural Language Understanding (NLU), GPT, Generative Pre-trained Transformers (GPT), Accessibility, Location Services, Audio, Online Payments, Web Platforms, SVG, OpenAI GPT-3 API, OpenAI GPT-4 API, Server Security, WebAuth, Secure Multi-party Computation, Data Analytics, 360° Video, Photogrammetry, VR Interfaces, QA Testing, OpenAI, ChatGPT, Visual Effects (VFX), Character Rigging, Payment APIs, SAP, Video Streaming, Vercel, Apollo, LangChain

2012 - 2015

Bachelor's Degree in Game Design

Mediadesign Hochschule - Berlin, Germany

NOVEMBER 2018 - NOVEMBER 2021

AWS Certified Developer Associate

AWS