There is a wide mix of expertise within the team at ITSS to ensure that we have the knowledge to provide complete end to end software solutions in the financial space. The team consists of  tax consultants, software developers, business analysis’s, test engineers, UAT specialists and customer services personnel.

John Twomey

Managing Director

I co-founded the company in 2008 with Finbarr & Orla. Together we strive to provide first class products and services. I head up training and sales of the tax software and most likely will be the one you will meet at one of these events.

Finbarr O Connor


Hey! I analyse and specify the legislative changes to ensure the software is continuously up to date. If you’re looking to challenge our opinion on Tax legislation then I will be the one to deal with your query

Orla O Shea


If you are considering a project or wondering how to streamline a process within your firm, then talk to me. While we are tax experts first, we also work on many other projects, from software integration, rewrites of legacy software to simple applications to help streamline processes within your firm.

Paul Flynn

Software Developer

I’m the guy who heads up development on the Personal & Corporation tax software. I have worked on the tax products for almost 10 years. As an unintended consequence I have built up 10 years of tax software knowledge along with understanding of the needs of accountants and tax advisors, this allows me to adapt the software quickly to meet the needs of the user.

Eoin Prout

Software Developer

Leading the development on new projects, I have extensive experience in green field as well as legacy software development. I initially started working on tax compliance software back in 1999 and since then have gained in-depth knowledge across various sectors.

Mark O Sullivan

Software Developer

With many years software development experience in the UK, I joined ITSS in 2011. While I work on various projects my expertise lies in ixbrl and web-services.

Airton Esmerio

Software Developer

While living in Brazil I developed and regionalised financial software. Since moving to Ireland, I have worked with ITSS on various projects for the accountancy sector.

Flora Weiler

Test Engineer / User Acceptance Testing

My role covers UAT and testing on the products. As well as accuracy I also ensure that you will have the best user experience.

Tim Hervey

UK Compliance Analyst

I have worked in the tax profession for over 40 years. I qualified and became a member of the Chartered Institute of Taxation (CIOT). I progressed to a Tax Manager role at Arthur Andersen with a predominantly corporate client portfolio. Since March 1996, I have worked in the tax software industry – providing my tax knowledge and experience into tax software products. Since its inception, I have been the lead tax professional working on the Sage Corporation Tax product.

Rose Castro

Senior Test Engineer

I have always loved the testing area and feel very lucky to be able to work with it. Every day I think about how I can be better in every way to maintain the high standard of our products and services.

Micheal O Brien

Customer Services

I’m Micheal, I am sure I have spoken to many of you over the years. I cover the phone and email support for the the Personal and Corporation tax products. If you need any help, I am more than willing to take your call and assist.