
Cristian Grigoras
Verified Expert in Engineering
Full-stack Developer
Bucharest, Romania
Toptal member since May 2, 2022
Cristian is a full-stack developer and software engineer with over eight years of experience in the banking and adtech industry. He focuses on using C#, .NET, and SQL while following the Agile and Kanban methodologies. As a results-oriented professional who is comfortable switching between various architectures and designs, Cristian enjoys challenges and finding innovative solutions that suit the clients' needs.
Portfolio
Experience
- Data Structures - 9 years
- .NET - 9 years
- Visual Studio - 9 years
- C# - 8 years
- MySQL - 7 years
- .NET Core - 5 years
- Algorithms - 5 years
- PostgreSQL - 2 years
Availability
Preferred Environment
MacOS, Visual Studio, .NET Core, PostgreSQL
The most amazing...
...thing I've created is an AI module to compute the complexity of a PDF file to see if it renders on the back end or front end.
Work Experience
.NET Developer
FlipGive Inc.
- Developed a package for .NET Core that encrypts and decrypts messages (payload to token) exchanged with the FlipGive platform.
- Publish the NuGet package on nuget.org so that any client can use it.
- Wrote clear documentation on how to install and use the library.
- Wrote unit tests for every case in which encrypting and decrypting might be needed.
.NET Full-stack Developer
Three Five Two, Inc.
- Developed a new award property in the system. A website where users can nominate companies and inventions at certain categories (integrated with a payment system).
- Developed a website where admins can see the entrants' entries and configure categories and other things.
- Created an audit page where judges can review nominees and select a winner.
- Fixed bugs on the system using Monday.com as the reporting tool.
.NET Developer
TBC Bank - Main
- Finished my work on the library that can be injected for authorization and authentication in any of its microservices.
- Migrated all routes in the transfer templates area to be used as a proxy to an old system.
- Created a lot of unit tests for the system in order to keep and get 80% coverage.
.NET Full-stack Developer
Three Five Two, Inc.
- Developed a two-factor authentication on a legacy .NET framework project.
- Added new reports to a .NET project using SQL database and entity framework.
- Implemented Google Sign-In feature to an existing application.
.NET Developer
Azavar Technologies Corp
- Worked on legacy C# application and developed new features for it. Added new pages for a specific role, secured so that only that role can see them. Added new reports for those roles.
- Tracked and fixed bugs using Jira as a reporting tool.
- Developed a new tool in the automation process where you can upload an excel file with addresses to be queried over an API to check the jurisdiction where they belong. Results were also saved to a database for a fast response the next time.
Senior Back-end Engineer
Invibes Advertising
- Contributed to various platforms, such as TCF module, geotagging that connects users with an ad, and a big data service that transforms attributes received from partners.
- Created a list of users (IDs) with some defined attributes using the Bloom filter algorithm for big lists and HashSet for small ones. Synchronized a list of IDs created by some defined features with the ad server.
- Merged IDs into the family if they had common identifiers.
- Contributed to the capping list service that can cap users, write IDs to files from the ad server, read ad event viewer, perform database shard, and create files for IDs.
- Monitored a suite of services to schedule and run database and Windows scripts and display results on each run.
- Wrote different scripts such as .NET scripts that needed to run on big DB, scripts to unmerge families of IDs on big sharded DB, scripts to modify attributes given by a particular provider, and scripts to clean only families made by identifiers.
- Built a new framework in .NET Core and worked on the core SFTP reader, email sender, and encryption.
- Integrated a test framework, changed communication between two apps from API to WebSocket, bundled enums to JavaScript, and organized workshops for a development team.
Senior Full-stack Developer
Intralinks
- Developed an application to view PDFs and other files online using WebViewer, WOPI protocol, Office 365, and SharePoint.
- Created an AI module to estimate the complexity of PDF documents through multiple linear regression with continuous learning.
- Optimized the application to save RAM and modified algorithms and patterns for GC to clean the memory.
Team Lead
Societe Generale
- Conducted regular meetings with people from the team, guided them, and managed projects between France and Romania.
- Supervised the eDirectory, a massive database with people worldwide working in SG, all subsidiaries, banks, and every entity involved in the company.
- Migrated the applications from virtual machines to Docker.
Senior Software Engineer
Societe Generale
- Created a web application where policies could be defined and assigned to a group of users.
- Built a Windows service that read, parsed, and sent logs to a database and a web application that read the database and displayed the results using a filter feature.
- Contributed to the AD provisioner and ISO connector projects with an active directory by creating, updating, or deleting different Windows and web services features.
- Performed mapping and worked on interfaces of CryptoManager—a WPF desktop application to manage crypto certificates from email—to send trades from the XOne system to MarkitWire API.
- Imported rules from an EMT file used to accept a trade-in MarkitWire.
Associate Software Engineer
Finastra
- Solved bugs in C++ and C# on the back-office servers of Sophis product, optimized algorithms, and debugged using Visual Studio.
- Acted as the main developer of the STP Omgeo server and developed an email module for the application.
- Moved the STP Omgeo server from C# hardcoded values to C# combined with XSLT to enable customers to change their values.
Experience
Ambiental Intelligence for Android Devices
https://github.com/andreiolaru-ro/AmIciTy-incubatorACCOMPLISHMENTS
Artificial intelligence scenarios based on the platform we developed:
• detection of the user's location based on a nearby wireless network
• communication between devices such as laptops, mobile phones, and computers
• detection of ambient noise levels and the users' movements sent to other devices
Tron Bot
https://github.com/grigoras/tron/blob/main/tron.cppThe main idea was to find the inflection points and fill the most significant room. When meeting an opponent, it tries to block it, using a classic minimax algorithm with a heuristic one.
Sync Service
The service works with three workers; each can have multiple parallel instances—reader, transformer, and writer. Workers communicate using the .NET channel.
Education
Bachelor's Degree in Computer Science
Politehnica University of Bucharest - Bucharest, Romania
Skills
Libraries/APIs
Entity Framework, Backbone.js, Node.js, React, Web API, REST APIs
Tools
Visual Studio, Dapper, MSBuild
Languages
C#, C#.NET, C++, Java, Kotlin, Python, SQL, XML
Frameworks
.NET Core, .NET 5, .NET, Entity Framework Core, AngularJS, Razor, Blazor, Angular, Windows Presentation Foundation (WPF), Bootstrap, ASP.NET Identity, IdentityServer 4, Ruby on Rails (RoR)
Paradigms
Microservices, CQRS, Design Patterns
Storage
PostgreSQL, MySQL, Redis Cache, MongoDB, Elasticsearch, JSON, Microsoft SQL Server
Platforms
MacOS, Linux, Docker, Oracle
Other
SFTP, Algorithms, Data Structures, Programming, Sharding, Big Data, Channels, Machine Learning, SDKs, Back-end, SDK Development
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
Share your needs
Choose your talent
Start your risk-free talent trial
Top talent is in high demand.
Start hiring