Roman Shevchenko
Verified Expert in Engineering
Full-stack Developer
Belgrade, Serbia
Toptal member since July 3, 2019
Roman is a full-stack developer and database designer with great attention to detail and team spirit. He takes the initiative to communicate ideas or architectural suggestions to maximize efficiency and minimize expense and effort, which is a win-win for everyone. Roman's areas of expertise include Node.js, TypeScript, .NET, Java (Kotlin), Go, PHP, Transact-SQL, MySQL, NoSQL, and interoperations between them, both on-prem and cloud deployment, design and implementation of APIs and protocols.
Portfolio
Experience
Availability
Preferred Environment
Visual Studio Code (VS Code), Visual Studio, IntelliJ IDEA, RStudio
The most amazing...
...project I've worked on is a private byteball fork, a blockchain or DAG that is confirmed by signatures of the majority of trusted nodes.
Work Experience
Cryptographic Engineer
Ribose
- Solved various technical issues of the RNP library and applications, including Unicode support on Windows.
- Added additional options for command-line interface (CLI) key generation, e.g., key expiration date.
- Adjusted RNP's CMake project for building with Visual Studio tools.
- Set up GitHub Action handlers for CI testing on various platforms, including Windows, Ubuntu, CentOS, and Debian.
TypeScript and Kotlin Developer
FlowCrypt
- Revamped the codebase related to the OpenPGP.js library, including key management, encryption, and decryption, for robust email security.
- Enhanced email security by implementing S/MIME message signing, encryption, and decryption using the PKCS #7 standard, bolstering data protection.
- Successfully upgraded the extension to OpenPGP.js v5, enabling vital library calls within Firefox content scripts for seamless operation.
- Improved message decryption support for incoming messages generated by various mail applications, including Thunderbird and ProtonMail.
- Elevated the development process by creating a streamlined framework for accessing Gmail and other servers, reducing errors, and promoting more efficient development based on the established framework.
- Overcame communication challenges between extension frames and Gmail pages, implementing secure messaging using window.postMessage and AES-GCM encryption for seamless and protected interaction.
- Expanded continuous integration (CI) capabilities by integrating Puppeteer-driven tests, significantly enhancing test coverage and automation. Also, contributed to Semaphore CI and Git Hooks automation, streamlining the build and deployment processes.
- Actively participated in peer code reviews for the FlowCrypt browser extension and the back-end projects (Kotlin, Java, jOOQ, and Javalin) that facilitated the extension's setup and functionality, ensuring code quality and collaboration.
- Contributed pull requests to repositories https://github.com/openpgpjs/openpgpjs and https://github.com/openpgpjs/web-stream-tools to facilitate seamless integration into the project I've been working on.
Lead Software Engineer
IX-7 Asset Management SA
- Designed and optimized an MS SQL database with triggers, custom CLR aggregate functions, and table-returning functions for efficient financial metric calculations. Maintained schema using SQL Server Data Tools (SSDT).
- Established heterogenous replication between MS SQL and MySQL using SymmetricDS, ensuring data consistency across platforms.
- Designed a MySQL database for a WordPress-powered website, implementing stored procedures and views to enhance data management.
- Developed a feature-rich WordPress website with PHP back-end, integrated FusionCharts, and seamlessly connected MySQL, MS SQL, and MongoDB databases.
- Enhanced a legacy ASP.NET Web Forms application by integrating single sign-on (SSO) through IdentityServer4 for improved security and user experience.
- Created a SOAP web service using .NET and developed a PHP client to enable efficient communication between systems.
- Led a team in successfully developing multiple Angular-powered sites with responsive design, seamlessly transforming them into progressive web apps (PWAs) for enhanced user engagement and mobile accessibility.
- Implemented single sign-on (SSO) using IdentityServer4 and incorporated two-factor authentication (2FA) with Twilio integration, providing enhanced security features as a team leader.
- Set up Azure CI/CD pipelines with on-premises server deployment via Azure agents, streamlining the development and deployment process.
- Developed a Saferpay payment system plugin and custom document templates for nopCommerce 3.90, contributing to eCommerce functionality and customization.
Developer
0chain
- Addressed and rectified bugs while implementing updates to enhance the efficiency and reliability of the Merkle Patricia Trie within the blockchain engine.
- Undertook significant enhancements to the module responsible for persistently saving the currently computed state, optimizing its performance, and integrating it with RocksDB for efficient data management.
- Conducted intricate integration tests involving multiple nodes running within Docker containers, demonstrating proficiency in ensuring the seamless interaction and functionality of the blockchain system.
Freelance Web Developer
Toptal Clients
- Designed and implemented a Node.js and TypeScript-based REST API with Express.js, routing deployed as a Google Firebase function.
- Set up a Google Firebase hosting for a simple web front end.
- Used TypeScript-JSON-validator to generate DTO validation based on the TypeScript source code and annotations.
- Integrated Firebase Authentication into the plain REST API, specifically Firebase ID Token.
- Implemented persistence with Google Cloud Firestore featuring transactions, Batch writes, and partial updates.
Lead Software Engineer
Millix Foundation
- Contributed to a fork of the distributed blockchain system (https://github.com/byteball/ocore), utilizing Node.js for back-end development.
- Enhanced the network communication protocol, optimizing it for increased robustness and efficiency, resulting in a more lightweight operation.
- Redesigned SQLite and MySQL database schemas to improve the storage efficiency of the directed acyclic graph (DAG), significantly enhancing data retrieval and storage processes.
- Engineered a user-friendly web interface for streamlined transaction entry, facilitating efficient debugging and testing.
- Implemented client-side JavaScript for secure key derivation and ECDSA signing, bolstering system security and user data protection.
Collaborator
Aminal Open-source Project
- Made substantial improvements to the Aminal open-source project.
- Added support for various terminal modes to meet vttest requirements.
- Implemented underline and inverse rendering using OpenGL.
- Added support for numerous OSC and CSI control sequences.
- Implemented an extended mouse support using OpenGL.
Senior Software Engineer
Logican Solutions
- Participated in the design and development of a comprehensive financial management system, focusing on integrating advanced technologies and third-party services to enhance operational efficiency and data integrity.
- Contributed to the adoption of SQL Server Data Tools (SSDT) and Entity Framework, employing a database-first approach to enhance system architecture and maintainability.
- Helped centralize core functionalities by creating a robust business logic layer, enhancing system maintainability and clarity in separating concerns.
- Contributed to enhancing the application’s user interface by utilizing Kendo UI controls, improving user interaction through intuitive and appealing design elements.
- Assisted in the integration with external financial services, like Experian and Kontomatik, to automate critical data acquisition processes and expand system capabilities.
- Supported team efforts in adopting best practices in software development and project management, contributing to continuous learning and process improvements.
Software Developer
Atlas Labs
- Implemented Auto Configuration Server according to TR-069 specifications. MSSQL database is used for storing configuration parameters reported by the router devices and queuing configuration tasks like firmware upload, parameter updates, and others.
- Worked on the project where the transport agent was initially supposed to be built upon the WCF infrastructure, but as the protocol occasionally uses non-SOAP empty body POST requests, another solution was needed.
- Solved the problem by building the agent upon the WebAPI framework from Microsoft.
Lead Software Engineer
A1 Media Research, Inc.
- Designed Couchbase buckets and Elasticsearch indexes. Created queries to Elastic, including aggregate queries. Adapted .NET client using Elasticsearch.Net and NEST libraries.
- Improved a scraper written in C# used to scrape the whole range of international media, blogs, and microblogs.
- Developed C# Web API back end for the internal website and some updates to the AngularJS front end.
- Improved a legacy Windows Presentation Foundation (WPF) application by adding new forms and reports.
Lead Software Engineer
Global Consulting Group, JSC
- Developed a brokerage database and back end consisting of various nodes communicating via Protobuf-based protocol.
- Built a WPF MVVM front end and parts of a Kendo UI web client.
- Integrated the brokerage system with Moscow Interbank Currency Exchange (MICEX) and the Russian Trading System (RTS) stock exchange.
- Implemented conditional orders, specifically stop loss, stop limit, and one-cancels-the-other (OCO) groups.
- Designed and implemented a high-throughput signature verification server with caching for each order placed.
- Implemented the Internet Explorer add-on for cryptographic keypair generation and certificate signing request submission using a page.
Software Developer
Rambler Internet Holding
- Took part in developing a FreeBSD/C++ internet indexer, with indexes divided into shards.
- Tweaked search results, mapped search queries to shards, and reduced the results.
- Developed extra features like adult content filtering.
Software Developer
JC System Integration
- Developed a multi-user video and audio manipulation software for TV broadcasts.
- Implemented custom controls using C++ (1st version) and C# (2nd version).
- Designed an MS SQL database for concurrent project editing with optimistic locks and update notifications.
Lead Software Developer
Intechform System Integration
- Developed software for ICPDAS micro-controllers running the MiniOS7 operating system for collecting data from several electronic volume converters (flow computers) measuring gas consumption, including SEVC-c/Corus.
- Built modules to collect data in real-time or periodically via RS-232 or RS-485 ports using Modbus and similar protocols and stored the collected data in the EVC's flash memory.
- Developed a module to send the collected data to the head office upon incoming connections using a custom protocol.
Software Engineer
X5 Retail Group
- Developed a 3-tier architecture for a high-load online discount system.
- Designed database, protocols, and transport agents for mobile top-ups using C++ and Oracle. The turnaround time between POS and mobile operators was under two seconds.
- Developed a thin client for PalmOS barcode scanners using CodeWarrior and server-side Java scripts for stock control.
- Developed a thin client with HTML and JavaScript and the server-side Java scripts for Symbol micro-kiosks, specifically price-checkers.
- Integrated data collection from work-time control devices using C++.
Software Engineer
FlexTel Service
- Designed and developed a high-reliability text message delivery system for sending to pagers, mobile phones, and email.
- Created and developed the database, accompanied by delivery agents, sending messages over UCP, POCSAG, and SMTP protocols.
- Developed an inbound SMTP server for automatic message redirection to mobile devices.
- Participated in the PBX telephony server development for its E1 line and Dialogic card.
Experience
AI-powered Messaging Assistant
For the front-end, I utilized React Native to support multiple platforms efficiently. Also, TypeScript was used to enhance development efficiency and maintainability. The back-end was built on a robust Node.js/Express.js framework, ensuring fast and efficient server-side operations. TypeScript is used to unify development practices with the front end, reducing complexity and cost. Additionally, I integrated TypeORM for flexible and reliable database connectivity and incorporated OAuth for secure user authentication, safeguarding user data and interactions.
A cornerstone of the application is its commitment to user privacy. It is designed to ensure that neither messages nor ChatGPT inputs and outputs are stored in the back-end database.
Progressive Web Apps for Customers and Company CRM
1. A fintech customer portal PWA: The objective was to enhance customer experience and provide insights into investment portfolios and performance charts. Its key include are a display of investment portfolios with a robust, user-friendly interface for tracking and analyzing financial assets and dynamic performance charts for a visually appealing representation of investments
2. CRM system PWA for managers. The objective was to streamline client management for efficient account handling. Its key features are a fine-tuned system to streamline the organization and tracking of potential clients, effectively converting them into customers, and Financial transaction entry— the CRM PWA allows manual entry of financial transactions
My key contributions:
Front-end: Oversaw Angular front-end development, ensuring a user-friendly interface for both PWAs.
• Web API: Led the design of the web API tier, optimizing communication for a smooth user experience.
• Database design
• SSO: Led a security upgrade with SSO via IdentityServer4 and 2FA using Twilio, enhancing protection.
• CI/CD: Streamlined tests and deployments to on-premise IIS servers with Azure pipelines.
Flowcrypt Browser Extension
https://flowcrypt.comMy key contributions:
• Established an efficient framework for accessing Gmail and other servers, minimizing code redundancy and promoting effective development.
• Restructured the codebase to utilize the latest version of the OpenPGP.js library.
• Added a feature to use X.509 family keys for S/MIME message signing, encryption, and decryption using the PKCS #7 standard.
• Significantly improved Puppeteer-driven tests to enhance continuous integration (CI) capabilities.
• Enhanced message decryption support for incoming messages from various mail applications, including Thunderbird and ProtonMail.
• Actively participated in peer code reviews for the FlowCrypt browser extension and associated back-end projects, ensuring high-quality code and collaboration.
My contributions are publicly available in the Github.com repository.
Media Research Project
A sophisticated scraper aggregated posts and comments from national social networks, streamlining data collection. Users could group posts by events and assess audience sentiment through a positive/negative response ratio.
During the phase-out, I provided crucial support and hotfixes for a legacy WPF/MS SQL project, ensuring a smooth transition between systems. This project showcases my proficiency in diverse technologies, from data aggregation to sentiment analysis, emphasizing efficiency and continuity throughout the lifecycle.
IVA & Debt Management Software
https://www.logican.co.uk/iva-debt-management-software/My participation included:
• Database design and deployment: Leveraged the power of a well-structured database built using SQL Server Data Tools (SSDT), ensuring optimal performance, scalability, and maintainability.
• Entity framework model generation and fine-tuning (database first): Utilizing the efficiency of Entity Framework, the project implemented a database-first approach to simplify model generation. Subsequently, the model was manually fine-tuned for complex reports and data manipulations.
• Various Kendo UI controls: Elevated the user interface with a rich set of Kendo UI controls, including implementing a hierarchy grid, providing an intuitive and visually appealing experience.
• Integration with 3rd-party services: Seamlessly integrated with third-party services such as Experian and Kontomatik, expanding the functionality and scope of the financial management system by automating debt and bank account data acquisition.
Back End for a Dating Application
In addition, I established Google Firebase hosting to support a straightforward web front end connected to the API. To ensure smooth collaboration with iOS and Android developers, I provided them with comprehensive specifications on how to consume the API efficiently.
For robust data validation, I employed the typescript-json-validator tool, generating data transfer object (DTO) validation based on TypeScript source code and annotations.
Moreover, I seamlessly integrated Firebase authentication, specifically Firebase ID Token, into the plain REST API. This enhances the security and integrity of the application.
On the persistence front, I implemented a sophisticated solution using Google Cloud Firestore. This includes advanced features such as transactions, batch writes, and partial updates, ensuring a resilient and scalable foundation for the dating application.
An Online Tiered Loyalty System for a Large Grocery Store Chain
Additionally, I engineered the entire database, incorporating complex and high-performing queries to enhance system efficiency. This involved a deep dive into optimizing data storage and retrieval processes, ensuring the system could handle large datasets without compromising speed or accuracy. This comprehensive approach underscores my skills in creating a robust and efficient system, spanning from architecture to database design.
Developing a monitoring application using MFC technology was also critical to this project, allowing for real-time system performance tracking and issue resolution.
Mobile Top-ups Infrastructure for a Large Grocery Store Chain
To further enhance operational efficiency, I developed a specialized tool. This tool empowered accountants to complete or roll back stuck transactions manually and featured advanced capabilities, including signing, encrypting, and sending daily reports to operators for streamlined reconciliation processes.
Online Trading System
A standout feature was the real-time data delivery with minimal latency. Back-end modules cached critical data, enabling effortless live quotes for users. This empowered traders to monitor equity balances and access up-to-date chart data for informed decisions in dynamic market environments.
Strategically leveraging Entity Framework, we ensured rapid development and synchronized complex queries with the evolving database structure.
Beyond the core modules, a high-throughput cryptography service revolutionized order verification, delivering security and speed within milliseconds. Additionally, a browser plugin facilitated client-side key pair and certificate signing request (CSR) generation, streamlining private key cryptography for a seamless and secure trading experience.
Byteball Fork
In translating functional requirements, I implemented codebase changes, strategically rearranged node interactions, and executed meticulous test plans. Team-led algorithm and architecture optimization ensured scalability and speed, ensuring efficient blockchain operation in various scenarios.
We extended protocol functions into REST API functions, maintaining a consistent approach to security. To uphold code quality, we thoroughly analyzed open-source contributions. I focused on hierarchical deterministic key generation using the Bitcore library, adjusting it to meet our project's specific needs.
Adhering to rigorous security policies, we identified potential attack vectors and vulnerabilities. All work underwent checks for grammatical, structural, organizational, and thematic consistency to integrate seamlessly within the entire codebase.
Power BI-driven Financial Dashboard with Custom Authentication
The dashboard's strength lies in its custom security extension, a solution I developed. This allows users to use credentials from our own authentication system to access the reports. Our on-prem SQL server hosts financial data and user information with access scopes and hashed passwords, ensuring data confidentiality.
Upon logging into the report server, data queried for reports is restricted based on the user's access scope. The security framework, implemented by me in conjunction with Power BI's row-level security feature, guarantees a robust and tailored access control system.
Efficient Financial Data Computation and Integration Project
A significant challenge arose in computing intricate financial metrics using standard SQL queries, leading to the creation of a resource-efficient CLR-based aggregate function. Further optimizations focused on adjusting table indexes for peak performance.
Financial metrics were then distributed using SymmetricDS to isolated databases supporting .NET and WordPress sites using MySQL. I honed my MySQL programming skills to craft user-centric queries for the WordPress site.
Additionally, I guided developers in query construction and database structuring, ensuring a smooth integration process. Collaboration with database administrators resulted in a successful email-sending integration, using triggers to initiate communications under specific conditions.
Fintech Service Landing Page Customization
https://ix-7.com• Spearheaded the customization of a WordPress-based landing and showcase site for a fintech client, focusing on personalized investment portfolio generation.
• Implemented an innovative feature allowing anonymous users to input investment preferences, generating tailored recommendations through dynamic visualizations using the FusionCharts library.
• Integrated a sophisticated user interaction bot, enhancing customer engagement by capturing preferences through conversational inputs. Preferences were stored in MongoDB, which also supported request throttling to ensure system
reliability.
• Leveraged MySQL for robust back-end data management, supporting the core functionality of investment recommendation generation.
• Enabled seamless user transition from the landing page to the main subscription-based platform, utilizing SOAP services to transfer portfolio data efficiently.
• Developed multilingual promotional pages equipped with an unsubscription feature to broaden market reach and enhance user experience.
Retail Compliance Application
https://www.retailguardian.comMy role in its development included creating a subsystem for managing staff schedules, covering holidays, sick leaves, and more. Despite the library's early development stage, the application took advantage of the Syncfusion library for scheduling UI controls and PDF report generation.
By directly communicating with the library's developers, I overcame challenges and implemented workarounds to enhance functionality. Additionally, I integrated the MessageBird library for SMS communication, further expanding the application's capabilities by enabling automated messaging features. This experience not only sharpened my technical skills but also provided valuable insights into handling library limitations and integrating third-party APIs.
Aminal (Now Darktile) – GPU Rendered Terminal Emulator
https://github.com/liamg/darktileAt the heart of this endeavor was a deep dive into OpenGL intricacies, where I honed my skills in graphics programming. My contributions were made in collaboration with a highly professional team, ensuring that every enhancement aligned with the project's goals.
As a valued contributor, my focus spanned from implementing support for the emulation of various terminal modes to integrating Sixel rendering and ensuring cross-platform compatibility, addressing a range of issues.
Auto Configuration Server (ACS) for Router Devices According to TR-069
https://en.wikipedia.org/wiki/TR-069The database stores configuration parameters from the devices and efficiently queues various tasks. Initially planned on WCF infrastructure, it was later discovered that the TR-069 protocol occasionally uses an empty body POST request (to enable bidirectional requests over HTTP), not strictly conforming to SOAP specifications. To address this, the transport agent was redesigned using Microsoft's Web API framework in C#.
This transition successfully addressed the challenge posed by the protocol's occasional use of empty body POST requests. The transport agent ensures reliable and compliant communication with the devices, enhancing the ACS performance and adaptability. The MS SQL database remains instrumental in managing configurations and queuing tasks, providing a comprehensive solution for remote router configuration.
Rambler Internet Search Engine
https://www.rambler.ru/The choice of C/C++ and STL for node development reflected a commitment to performance and efficiency. These languages, known for their low-level capabilities and optimization opportunities, allowed Rambler to create nodes that could handle the substantial computational demands of crawling, indexing, and serving search results.
Deploying on FreeBSD servers highlighted a preference for a robust and Unix-like operating system known for its stability and scalability. The choice of FreeBSD showcased a dedication to providing users with a reliable and efficient search experience.
AWS Lambda Development
The Serverless Framework was used for easier deployment of the project to AWS and potentially to other platforms.
SaferPay Payment Plugin for nopCommerce 3.90
Beyond providing a straightforward payment option, the plugin supports recurring payments. This feature allows my client to offer subscription services, membership plans, and other recurring billing models effortlessly. The implementation of recurring payments enhances the versatility of the plugin, catering to businesses with subscription-based revenue models.
Stripe Checkout Upgrade for SCA Compliance
https://yspi.ie/Fast and Reliable Alarm Transport and Conversion Module for Medical Devices
The module also provides status feedback on the link to the external system to the original sender, making the integration complete and reliable. An ASP.NET Core application was built to host the module.
Multithreaded Control Service for IoT Omni-based Scooters
Operating within a Mono environment on Amazon EC2, the service is designed to handle lock/unlock operations and firmware updates, all orchestrated through a PostgreSQL database.
My extensive experience in multithreaded architecture and diverse protocol knowledge proved instrumental. I identified some severe flaws in the thread interoperation of the codebase and implemented necessary updates to significantly enhance reliability, thereby making the product more competitive in the market.
Advanced Metering Infrastructure for Industrial Boilers
The head office server dispatches firmware updates to devices, managed adeptly by developed firmware code. Controller flash memory stores received data and updates, released after a successful head server session for efficient data management.
The head office software built in C#/.NET includes a communication module on a custom protocol and a WinForms GUI application.
Solidity to Go Transpiler PoC
Another challenge was to extract Solidity function modifiers to rebuild them in Go, preserving a possible chain of invocations in the correct order.
Thus, the transpiler Go code maintained the nuanced behavior of the original Solidity smart contract.
Custom IQFeed Order Management and Chart Analyzer Platform
Order Management Platform
Interactive Brokers Order Management Plugin
Crypto Exchange Plugins for NinjaTrader
C#/QuickFIX Plugin for NinjaTrader
C++/ACSIL Studies for Sierra Chart
TASKS
• Created tailored ATR and RSI indicators that are exactly equivalent to NinjaTrader's indicators in output.
• Implemented Kase CD and Kase Peak Oscillator, Volatility Stop, Momentum, Adaptive CCI, and DamianiVolatmeter indicators based on NinjaTrader's code.
• Implemented gapless versions of a dozen of indicators.
• Re-implemented MetaTrader4's SuperADX, SupportingADX, and Chopy Market Index (CMI).
Most of the implemented studies support inputs based on other indicators and tick data.
Custom Request Processor for DataStax (Student Assignment - Java)
https://github.com/rrrooommmaaa/datastax-java-driverA custom request processor was implemented to return the Producer row result for CQL-compatible requests.
The solution:
• Is thread-safe.
• Stores temporary items in a queue and drains them whenever the consumer requests more.
• Has a non-blocking, lock-free queue-drain pattern using atomic variables (https://akarnokd.blogspot.com/2015/05/operator-concurrency-primitives_11.html).
• Uses ForkJoinPool for lock-free data pumpin.
• Supports Producer cancel to avoid data pumping when no longer required.
• Implements filter, map, and reduce methods for producers that allow a data flow preserving the features mentioned above.
• Covered with unit and integration tests.
Education
Master of Computer Applications (MCA) Degree in Information Technology
Bauman Moscow State Technical University (BMSTU) - Moscow, Russia
Skills
Libraries/APIs
Node.js, ODBC, JSON API, NinjaScript, Microsoft Development, Interactive Brokers API, Windows Development, REST API, FusionCharts, API Development, Sockets, Entity Framework, Microsoft Development, Web API, Protobuf, React.js, Experian, Stripe Development, Stripe Development, Twilio Development, Web API 2, Puppeteer, jQuery, AES, Telegram Messenger API, Standard Template Library (STL), OpenGL, Java
Tools
Visual Studio Development, NinjaTrader, Git, Syncfusion, Stripe Development, GitHub, C#, Apache Maven, Plesk, Terminal, Ninject, Subversion (SVN), Mockups, Firebase Authentication, ANTLR 4, Mocha, IntelliJ IDEA, Business Intelligence Development, CryptoPro, GPG, Java, Microsoft Access Development, Azure, Gradle, Eclipse IDE, GoLand, Firebase Cloud Messaging (FCM), MongoDB, DataStax, Dapper, Docker Compose, Webpack 4, SemaphoreCI, MessageBird, TeamCity, ChatGPT, Webpack
Languages
.NET, C#, JavaScript, T-SQL (Transact-SQL), XML, F#, VB.NET, TypeScript, C++, Java, SQL, Go, C++, Java, Visual Basic, PHP, Kotlin, YAML, Assembly, Pascal, VB.NET, Assembly Language, Solidity, R, Perl, Python, Java, C, MQL4, PHP
Frameworks
.NET, Web Development, ASP.NET, .NET, Kendo UI, ASP.NET, VB.NET, Express.js, Windows Presentation Foundation (WPF), Google Protocol Buffer, .NET Core, PEG.js, Swagger, Windows PowerShell, Serverless Framework, IdentityServer 4, JSON Web Tokens (JWT), Mockito, ASP.NET MVC, Mono, Divi, Jest, Boost, JUnit, Razor, Angular, Laravel, Symfony, ActiveX, ASP.NET Core 2, OAuth, Javalin, AngularJS, React Native
Paradigms
REST, MVC Design, Model View ViewModel (MVVM), Socket Programming, Database Design, Unit Testing, Asynchronous Programming, Database First, Model View Controller (MVC), Azure DevOps, Cross-Platform, DevOps, PKCS, Design Patterns, Database, Concurrent Programming, Business Intelligence Development, Code Refactoring
Platforms
Visual Studio Development, Telerik, Windows Development, WordPress Development, Oracle Development, Telerik, NetBeans, Azure, Ubuntu, Blockchain, Bitcore, Firebase, AWS Lambda, Cloud Engineering, Amazon EC2, Unix, Linux, Eclipse, RStudio, MetaTrader, FreeBSD, Docker, AWS, nopCommerce, MetaTrader 4
Storage
SymmetricDS, Database Modeling, SQL Server Data Tools (SSDT), SQL Server, Database Triggers, JSON, Database, Relational Databases, MySQL, SQL CLR, Couchbase, Elasticsearch, SQLite, PostgreSQL, Firestore, Database, SQL Server, NoSQL, IndexedDB, Oracle RDBMS, MongoDB, Firebase Realtime Database, AWS, Redis, RocksDB, Cassandra, MySQLi, XML, CQL, SQL Views
Other
Coding, Back-end Developers, APIs, RS485, RS-232, FIX Protocol, QuickFIX, Order Management, Windows Development, OpenPGP, Software Architecture, API Integration, Payment APIs, Payment Gateways, Integration, Multithreading, Open Source Development, Async/Await, TCP/IP, Protocol Design, 3D Secure, Open-source Software (OSS), Trading, Technical Leadership, Query Optimization, Code Review, Full-stack, FP&A, Database Schema Design, Software Requirements Specifications (SRS), Architecture, SSH, Modbus Protocol, SMPP, Windows Communication Foundation (WCF), SOAP, Cryptocurrency, SSL Certificates, Internet Information Services (IIS), Web App Deployment, Applied Cryptography, Web Development, PGP, Directed Acrylic Graphs (DAG), Serverless, Protocol Buffers, CLR, WebSockets, Chrome Extension Development, Distributed Software, CI/CD Pipelines, Asymmetric Encryption, SMS, Ajax, DOM, Advanced Encryption Standard (AES), Progressive Web Applications (PWAs), Back-end Developers, Smart Contract Development, Reconciliation, Byteball, PDF, Cross-platform App Development, SaferPay API, Authorization, System Security, Front-end Development, Backtesting Trading Strategies, Artificial Intelligence, IoT Protocols, GitHub Actions, Joi, OpenAI GPT-3 API, GPT-4, Crytographer, System Security, PWA, Full-stack, UI Development, OpenAI, Xamarin Studio, Dynamic Data Exchange (DDE), System Security, Firebase Hosting, TypeORM, Firefox Extensions, X.509 Certificates, S/MIME, Algorithms, Networking, SMTP, Protocol Development, Telephony, Paging, PBX, Firmware, Embedded Systems Engineering, Session Initiation Protocol (SIP), Data Communication, Algorithms, Apache Cassandra, Integration Testing, Fetch API, SIP, Optimistic/Pessimistic Concurrency Checks, Third-party Integration, Digital Signatures, Monorepos, System Security, Reporting, Charts, UX Development, Graphics Programming, Web Scraping, Dashboard, Plugin Development, Asynchronous I/O, Source Code Review, SSO Engineering, Landing Page Design, Medical Software, Bookkeeping, Stock Market Consulting, Chatbot Development
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