Jozsa Istvan
Verified Expert in Engineering
Software Developer
Brașov, Romania
Toptal member since December 8, 2020
Jozsa is a software developer passionate about coding, doing it both professionally and as a hobby for the last 15 years. Throughout his career, he has worked for small and large companies, such as Siemens and Waters Corporation. He tries to perfect himself to get the most out of his time by automating repetitive tasks, self-analyzing, and focusing on eliminating detrimental habits. Jozsa is always eager to learn from others and integrate best practices into his work.
Portfolio
Experience
Availability
Preferred Environment
Visual Studio, Windows 10
The most amazing...
...project I've worked on is a massive multiplayer online (MMO) game server with over 200,000 new subscriptions per month.
Work Experience
Senior Software Engineer
VIAVI Solutions
- Handled massive network traffic ingestion (5-80 petabytes/rack).
- Generated real-time KPI and statistics on the ingested data (e.g., VOIP audio quality, video latency, packets lost, retransmissions, etc.).
- Stored statistical data in a time series database and linked the statistical data to the logged raw network traffic.
- Provided a query interface where customers could visualize statistical data (e.g., the people someone talked to over VOIP on a specific date interval).
- Generated visualizations (e.g., the network traffic of this workstation and interface with repeating daily interval patterns). Generated baseline values for a specific workstation to detect anomaly network traffic.
- Created a web REST API for customers to query data for their custom-made visualizations.
Senior Software Developer
Online Freelance Agency
- Designed, implemented, and tested the audio and video player using SDL and FFmpeg with cross-platform support.
- Designed and implemented security software for ATMs. It is a 2.5 GHz radar system to detect objects behind customers (all meteorological conditions, night and day) and alert them of potential safety issues.
- Developed, implemented, and tested accounting software using C# WPF and SQLite.
- Monitored the hard drive location for file changes. When text or document file changes were detected, I created automation for versioning snapshots that users can manage in a UI and revert to specific versions.
- Converted the LinkedIn AI search module from Go to C language. Extended capabilities, scalable sharding support, and features with over 50 filtering and scoring options for AI.
- Developed a YouTube downloader to find matching music for the sound fingerprint to detect copyrighted material. Used Node.js on AWS.
- Built an Amazon email processing Lambda function using AWS Route 53, SES, S3, DynamoDB, and SQS.
- Designed, implemented, and tested software for network traffic encryption using a custom network driver to redirect all traffic into the SOCKS5 proxy and encrypt connections, even if they don't support SOCKS5.
- Implemented human emotion detection and talk statistics for video conferencing using machine learning and AI.
- Worked on the load-balanced file server with hundreds of millions of files supported by a low latency API for fetching and updating data.
Windows Service Developer
Instacollect, Inc.
- Created a solution for the application group to circular report heartbeat and the ability to supervise other applications in the group for integrity. Instantly kill rogue applications and restore missing applications.
- Built a Watchdog service to monitor application setting integrity.
- Created a Watchdog service to monitor application status: uptime and integrity.
Software Engineer
David Redmon Inc. dba PCORP
- Broke Sentinel HASP protection and unpacked enveloped applications to access static data and code in both 32-bit and 64-bit applications.
- Broke encryption type below Sentinel; the data was protected by unknown encryption. The application was written to try out all encryption types supported by a microcontroller AES_CBC_256_noAuth encryption was identified.
- Used a disassembler to identify the encryption, data format, and hashing codes.
- Wrote a virus to hijack target application code and broke encryption key so when encryption happened to dump the encryption/decryption key.
- Wrote a program to emulate all hashing algorithms supported by a microcontroller and broke hashing used for data authentication, and found the one that validates data integrity.
- Broke data format to replicate robot control protocol, a specific static analog signal generation had to be implemented. On a premade clock front, status change events had to be emulated.
- Implemented motion calibration to make robot movement look like it's moving in Cartesian space. Due to the physical layout, the robot's arm movement was in a multi-curved space which distorted any command issued to him.
SQL Expert
CIP BVBA
- Listened to the client's requirements. An older CRM that used Microsoft SQL needed to be converted into the new Odoo CRM database format.
- Proposed a solution to meet the client's needs and consider his options. He picked C# with Windows Forms for fast project delivery.
- Planned the project. Designed an accessible, easy-to-use UI with SQL credentials and a simple interface with tokenized queries. Exported it to a new DB format to a specified path.
Senior Image Processing Engineer
REV3AL LLC
- Designed, developed, tested, and delivered an API for an image registrar service that can detect already registered images containing 80% matching content.
- Delivered the API mentioned above, which resulted in the first customer making an order of 10,000 API calls so that they could register their NFT images and prevent others from copying and registering them.
- Used Jira to track planned tasks and active task statuses.
C Expert
Upsider, Inc.
- Re-implemented search engine for LinkedIn. Convert GO code to C. Scalable, shard-able, in memory cached instances.
- Remade data caching for faster and more efficient storage and access.
- Implemented an AI search feature. Generated search hit ordering based on user relevance scoring.
Windows Kernel Developer
Phase Five Systems LLC
- Implemented a virtual monitor driver to mimic a real monitor on which remote desktop data is rendered. 1:1 data rendering allows true font and data rendering without rescale distortion.
- Built an audio cable driver. It allows splitting input data streams to redirect part of them to a remote desktop connection.
- Gathered client requirements and translated them into technical solutions.
C Developer
Klever Thoughts Inc.
- Improved, maintained, and added features for cross-platform video inspection software. Rewrote the core engine to render 4K videos in real time. Improved Exif info extraction.
- Gathered customer requirements and translated them into technical solutions.
- Performed multi-platform 3rd-party library integrations, building, testing, and debugging of final software solution.
Senior Software Developer
Atos
- Wrote data replication, security layer, and licensing for the Nord Stream gas pipeline project.
- Upgraded the security layer between HFA phones and OpenScape 4000 servers.
- Rewrote a C++ MVC project into C# WPF to control the telephone connections.
- Created UI widgets in Qt for SCADA systems for oil and gas pipeline remote monitoring and management.
- Debugged real-time operating system issues on a custom hardware board to trace software issues.
Software Developer
Waters Corporation
- Provided a solution to reduce Pfizer login times from 15 minutes to 20 seconds, involving a workaround of Oracle SQL drivers.
- Improved SmartBear automated testing times by 50% by creating a plugin to cache object search results based on their hierarchy path. Reduced the testing times from seven to three hours.
- Created a demo solution to separate the back end from the front end to replace the old MVC technology stack with cross-platform solutions. The demo included PHP and Qt front end with a REST API back end.
Software Developer
Splash Software
- Maintained and updated MPEG4, H263, and H264 video decoders and encoders. Added multi-threading, GPU processing of data, different rate controls, CABAC, fade detection, and optional input of filters.
- Created a pilot project for the H265 encoder before the specification was fully released. It only included a baseline profile.
- Converted most encoders and filters to support DirectShow graphs, intending to fix constant issues with corrupted inputs and separate issues into multiple programs that could restart and resume separately in case issues arise.
- Developed a Google map overlay, which triggers a special offer popup to appear on the map as the users drive by different stores.
- Conducted a search engine comparison. This was a doctorate project where a custom search engine performance had to be compared with Google and Bing. The interface was created for human testers to rank the search result relevance.
- Performed a firewall modification. The firewall had to protect against SYN floods, DDoS attacks, service attacks, port exhaust attacks, and connection exhaust attacks. Hardware firewalls cost around $50,000 for such tasks.
- Set up raw video processing over the network. A large video stream had to be split over multiple processing PCs and combine results to be streamed due to memory bottleneck.
- Developed automation based on image recognition. Wrote the DLL in Assembly (ASM) for a C# project.
- Built a multiplayer online game server, including all development layers—planning, execution, testing, customer support, community management, forums, website, and payment platforms.
Experience
Massive Multiplayer Online 3D Game
https://github.com/Tudi/Descent-core• Infrastructure (find hosting, rent servers, use edge hosting, manage bandwidth, do statistics on latency, and rent connections between data centers)
• Security (firewalls, encryption, private networks, public networks, port forwarding, and auto banning)
• Load balancing (monitor service load, launch instances if needed)
• Server networking (public/custom protocols for data synchronization)
• Server DB (SQL, DBC, InMemory, and cold storage)
• Anti-cheating/security (private data protection, auto-detect cheating)
• Scripting (taking advantage of community contribution )
• External API (external guilds and chat integrations)
• Linking multiple products (websites, forums, payment systems, DB, firewalls, and content editors)
• Website (dedicated unique content)
• Payment (pay by phone, card, digital currency, and bank)
• Support (system to gather complaints, pinpoint issues, and create a traceable ticket)
• Community management (the heart of an MMO)
In the best months, it had 200,000 new users subscribed and gathered over $7 million in donations for upkeep.
Augmented Gaming
https://github.com/Tudi/GameOverlayMemory Profiler
https://github.com/Tudi/TempStorage/tree/master/HookMemoryAllocationsExecution Profiling
https://github.com/Tudi/TempStorage/tree/master/ProfileExecutionTimeQt Demo
https://github.com/Tudi/TempStorage/tree/master/QT_DemoAPIConsumeEducation
Master's Degree in Computer Science
Transilvania University of Brasov - Brasov, Romania
Certifications
Process Communication Model
PCM
Lean Six Sigma White Belt Certification
Lean Six Sigma Institute
UX Workshop
Mozaic Works
Certified WinCC OA Basic Training (ETM-WINCCO)
Siemens
Agile Software Development Using Scrum
Mozaic Works
Skills
Libraries/APIs
FFmpeg, REST API, DirectShow, Sockets, API, Standard Template Library (STL), Pthreads, Windows Development, API, Node.js, PayPal API, Microsoft Development, Google API, Azure Cognitive Services, Microsoft Development, Google Maps Development, Google Maps Development
Tools
ExifTool, C++, Visual Studio Development, Intel Parallel Studio, AMD uProf, Subversion (SVN), Intel Debugger, Git, GitHub, Apache, Excel Development, Windows Development, VPN, PuTTY, SmartBear Collaborator, WinCC Open Architecture, AWS, Amazon Simple Queue Service (SQS), Git, Valgrind, Makefile, Jira, Make, Tcpdump, Perforce, IBM Rational ClearCase, AWS IAM, CMake, Odoo, Interactive Disassembler (IDA), Sentinel, Windows Driver Kit (WDK), Wix Development, Docker Compose, VTune, Asterisk, FileZilla
Languages
C++, C, C++, C++, .NET, PHP, AutoIt, HTML, JavaScript, Pascal, C#, SQL, XML, Assembler x86, Lisp, VHDL, Java, Lua, Visual Basic, Flash ActionScript, Python, Visual Basic, CSS, Embedded C, Visual Basic, Python, Fortran, PHP 8, Assembly, Rust
Paradigms
Windows App Development, Desktop App Development, Object-oriented Programming (OOP), Concurrent Programming, Automation, REST, Automated Testing, Application Architecture, Socket Programming, Agile Development, Scrum Master Consulting, Microservices Development, Microservices Architecture, Unit Testing, Testing, ETL
Platforms
Microsoft Development, Windows Development, Windows Development, Windows Development, Win32, Windows Development, AWS IoT, Visual Studio Development, CUDA, AWS Lambda, Azure, AWS, Linux, Kubernetes, Docker, Software Design Patterns, Linux, Kernel, Amazon EC2, Cloud Engineering
Frameworks
ASM, Qt Development, Selenium, .NET, Windows Presentation Foundation (WPF), .NET Core, Realtime, Boost, Qt 5, Ghidra, Spring Boot, Flask
Storage
MySQL, JSON, MySQL, Amazon S3, AWS, Google Cloud Development, Database, PostgreSQL, SQLite, Relational Databases, Database, SQL Server
Industry Expertise
Lean Project Management
Other
Video Encoding, Performance Tuning, Debugging, Profiling, Data Structures, APIs, Screen Scraping, Performance, Debugging Tools, API Integration, Image Processing, Transmission Control Protocol (TCP), Windows Development, Serializer/Deserializer (SerDes), ASCII, Software Development, Computer Vision, Data Compression, Data Compression Algorithms, Video Processing, Software Development, Minimum Viable Product (MVP), Low-level Programming, DLL, Application Performance Monitoring, Application Performance Optimization, Optimization, Performance Optimization, Solution Architecture, Networking, Multithreading, Video Streaming, GUI Design, Streaming, Computer Science, Client/Server Networking, Computer Networking, Memory Management, Game Development, Runtime Debugging, SQL, Software Architecture, TCP/IP, IPC, Architecture, Bots, 3D, Scripting, UI Development, Windows 10, Web Scraping, UTF-8, Reverse Engineering, Web Development, Game Development, 3GPP, RTPEngine, RTP, Session Initiation Protocol (SIP), Networks, Video Compression, QA Testing, WebSockets, Back-end Developers, Back-end Developers, Full-stack, Remote Rendering, Gaming, Network Protocols, FTP, SFTP, VoIP, Anti-tampering, Task Scheduling, Mathematics, Linear Algebra, MMORPGs, MMO, Massive Multiplayer Online Games, SVG Design, Graphic Design, 3D Graphics, Computer Graphics, Hardware Design, Compilers, UX Development, SSL, Amazon Route 53, UI Development, Encryption, Windows Development, Front-end, Front-end Design, Machine Learning, Low Latency, Discord Bot, PayPal Development, Network Configuration, Memory Profiling, Distributed Systems, Load Balancers, Site Speed Optimization, OCR, Image Recognition, Pattern Matching, Algorithms, Game Development, Graphics Processing Unit (GPU), GPU Computing, Streaming Data, Telephony, Software Design, Oil & Gas, System Security, SCADA, Reporting, Shell Scripting, Device Drivers, System Security, Proxies, Amazon API, Tesseract, Options Trading, Trading, Stock Trading, CI/CD Pipelines, Embedded Software Engineering, UI Development, Crytographer, Augmented Reality, Communication Coaching, Games, AWS RDS, Perceptual Hashing, FPGA, Lambda Functions, Serverless, Discord, Scraping, Speech to Text, Microcontrollers, Embedded Systems Engineering, Lean Project Management, Data, PDF, Game Development, Robotics, Pd64, Sentinel HASP, SIP, Chatbot Development, Processing & Threading, Key Performance Indicators (KPIs), 3D Rendering, Intel Transactional Synchronization Extensions (TSX), Message Queues, Renewable Energy, RTOS, Payment APIs, MSI, OT Security, PBX, Data Loss Prevention (DLP), Windows Kernel Drivers, Security, Digital Forensics
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