Profile image of yianniss
Flag of Greece Athens, Greece
Member since April 20, 2016
3 Recommendations


Online Offline
I am a results-oriented person with diverse set of skills. I have significant experience in MS Windows and Office technologies (VBA/Excel/Visual Studio/C++/COM/ATL/C#). I have also focused on linux and web technologies (Ubuntu/Eclipse/HTML/CSS/Javascript) and have developed for Android using both Java and the NDK.
$20 USD/hr
16 reviews
  • 88%Jobs Completed
  • 97%On Budget
  • 85%On Time
  • 31%Repeat Hire Rate

Portfolio Items

Recent Reviews

  • image of Daniele B. Project for Ioannis S. -- 2 $150.00 USD

    “Personal problems, didn't finish all the project. Very good released part, with his usual good quality code and expertise, can't give best ratio because project is incomplete for my purpose. Daniele”

  • image of Daniele B. REAL Angular expert to refactoring code (only Fixed Price, only suitable and quickly engagable) $440.00 USD

    “I believe Ioannis is between the best freelancer I ever found. Professional, attention to details, able to understand quickly the requirements or existing code, and last but not least, very high quality of code, different from many freelancers that simply produce something just works but without maintenance in long time. I suggest Ioannis over all. Great job!”

  • image of Jh O. vba logic & c# -- 2 $150.00 USD

    “A real expert. The job was quite tricky and subtle one. There was no problem with the communication. He worked in great detail and very well understood what was required. I would definitely recommend!”

  • image of Sorin G. Project for Yiannis S. $160.16 USD

    “I am 100% happy. Yiannis was fast, prompt, professional, knowledgeable. This was a small project but I will definitely ask for his help in the future. I recommend him. Thank you Yiannis!”

  • image of Federico M. Project for yianniss €450.00 EUR

    “Great job. He had to face some unexpected problems but everything works great right now.”

  • image of Alexander W. Components for web services access from Microsoft Office VBA apps €600.00 EUR

    “All aspects above were delivered as indicated. The pre-project phase was easy and simple to get to an agreement, the project-phase was very pragmatic and prethinking and the post-project phase continues with availability for questions in case such arise.”



Nov 2012

- Developed Dynamic RibbonX (now rebranded as Ribbon Commander). An MS Office dynamic UI framework for the Office Ribbon. (Core in C++11/COM/ATL, services on MS Azure in C++/Casablanca, proprietary graphics framework based on Win32/GDI/GDI+/WTL, .NET projections) - Worked extensively in Ubuntu Linux, focusing on C++ and web development (HTML/CSS/Javascript/Apache2/FastCGI) - Worked on several electronics projects (Arduino, Esp8266, ATMEL)

FO Tactical Developer

Aug 2011 - Nov 2012 (1 year)

- Developed libraries in C++, C#, VBA to extend the company's Excel platform focusing on performance, reliability, security and low-level control where necessary as well as client applications in VBA (Excel), C# (Winforms) and C++ (WTL). - Supported and enhanced add-ins both in C++ (COM, RTD servers, XLLs) and C# (VSTO, RTD, Managed XLLs). - Focused on security/auth infrastructure development for the excel platform, extending the existing VBA stack with C++/C# components where appropriate.

FO RAD Developer, Equities Desk (AVP)

Jul 2010 - Jul 2011 (1 year)

- Worked on the trading floor and directly interacted with traders/quants. - Developed and maintained applications in VBA (excel), C# and C++ (COM/ATL). - Paricipated in the migration of analytics libraries, and re-engineered a number of spreadsheets (including several mission-critical applications) with very good results/feedback. - Maintained and extended the existing VBA infrastructure focusing on reliability and good programming practices

Quantitative VBA Developer, FI Exotics

Nov 2009 - Jul 2010 (8 months)

-Developed and supported various exotics trade templates as well as other templates related to pricing and market data, which plugged into the C++ quant libraries through COM interfaces in VBA. - Developed / worked on the improvement of spreadsheets across the whole range of M+ templates, some of which were complex/heavy - enough to bring excel to its limits, with a focus on performance and reliability. - Delivered significant code/ spreadsheet performance improvements.

Financial Analyst, Risk & PnL team, FI Exotics MO

Apr 2008 - Nov 2009 (1 year)

- Delivered risk & PnL reports to the EUR desk in a timely fashion, often under significant time pressure, as part of a rotating shifts scheme. - Successfully developed key spreadsheet solutions aimed to improve team efficiency during the volatile period of late 2008. - Supported and enhanced complex and mission-critical Excel/VBA solutions. - Worked with a variety of exotic products from various perspectives (life cycling, trade reviews & bookings, maintenance, risk reporting etc).

Risk Management Consultant

Jul 2007 - Jan 2008 (6 months)

- Worked as a management consultant (EMEA region, commercial banks and building societies) - Dealt mostly with vanilla FI instruments such as bonds, swaps, futures, FRAs & vanilla options. - Used Excel extensively as a reporting tool & got exposure to classic risk management practices (VaR, stress testing, gaps, durations, hedging)


BSc in Statistics

2000 - 2005 (5 years)

MSc Banking & International Finance

2006 - 2007 (1 year)

MSc Computer Science

2015 - 2016 (1 year)


  • US English Level 1


  • Facebook Connected
  • Preferred Freelancer
  • Payment Verified
  • Phone Verified
  • Identity Verified
  • Email Verified

My Top Skills

Browse Similar Freelancers

Recently Published Community Articles