Company lists · Data refreshed September 2026

Top 25 Legacy system modernization companies based in Ireland

Name: Legacy system modernization companies based in Ireland
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 20, 2026 86 companies tracked

RevenueBase identified 86 legacy system modernization companies headquartered in Ireland as of September 2026 and tracks 3,984 professional contacts across them, including 2,201 with verified work emails. Dublin is the largest hub.

This list covers legacy system modernization companies headquartered in Ireland, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 20, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 20, 2026 86% judged on-target in blind review

86Companies

3,984Contacts tracked

2,201Verified emails

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The 25 largest legacy system modernization companies based in Ireland

Ranked by team size

Top 25 of 86 legacy system modernization companies based in Ireland, ranked by team size, largest first. Data refreshed Sep 20, 2026. RevenueBase Smart Search rates how each company's information relates to legacy system modernization companies: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Version 1	Indirect evidence	Dublin 1, IrelandHQ checked Sep 20, 2026	1,001-5,000	3,105 contacts →
	Indirect evidence “Version 1 is a leader in AI and digital transformation, partnering strategically with global organisations to transform and adopt technology and drive innovation in a responsible…” Source: RevenueBase Database · checked Sep 20, 2026
2	Presidio Europe & Asia Pacific	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	201-500	102 contacts →
	Indirect evidence “Welcome to the official EMEA & APAC page for Presidio.” Source: RevenueBase Database · checked Sep 20, 2026
3	JET BI	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	51-200	64 contacts →
	Indirect evidence “Jet BI is a certified software engineering and consulting company headquartered in Dublin, Ireland.” Source: RevenueBase Database · checked Sep 20, 2026
4	E-Celtic Limited	Indirect evidence	Dublin 8, IrelandHQ checked Sep 20, 2026	51-200	47 contacts →
	Indirect evidence “e- Celtic is a leading ICT company headquartered in Dublin, Ireland.” Source: RevenueBase Database · checked Sep 20, 2026
5	Sidero	Indirect evidence	Athlone, IrelandHQ checked Sep 20, 2026	51-200	44 contacts →
	Indirect evidence “GlobalLogic is a leader in digital engineering.” Source: RevenueBase Database · checked Sep 20, 2026
6	Client Solutions	Indirect evidence	Dublin 12, IrelandHQ checked Sep 20, 2026	201-500	39 contacts →
	Indirect evidence “Client Solutions is the Irish enterprise technology partner of choice.” Source: RevenueBase Database · checked Sep 20, 2026
7	Impact Engineering	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	23 contacts →
	Indirect evidence “Mission Statement: Impact Engineering Ltd strives to operate as a trusted automation partner, utilising a customer centric focus to combine our technical and business expertise…” Source: RevenueBase Database · checked Sep 20, 2026
8	Swappsi Software	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	17 contacts →
	Indirect evidence “Swappsi is an Irish-based software development company that specialises in Digital Transformation and dedicated to creating interactive solutions tailored to each client’s unique…” Source: RevenueBase Database · checked Sep 20, 2026
9	Tier3tech Support	Indirect evidence	Dublin 2, IrelandHQ checked Sep 20, 2026	1-10	11 contacts →
	Indirect evidence “Grow your business with Tier3Tech Give your business a more streamlined approach to growth by investing in technology that fits your business needs.” Source: RevenueBase Database · checked Sep 20, 2026
10	DAYNT	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	9 contacts →
	Indirect evidence “At Daynt, we are a boutique technology and professional services firm dedicated to helping startups, SMEs, and growing enterprises navigate their digital transformation journeys.” Source: RevenueBase Database · checked Sep 20, 2026
11	Wolf And OAK	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	9 contacts →
	Indirect evidence “We help companies achieve their goals by identifying the gap between where they are and where they need to be, by ensuring the deployment of best-fit technologies, the first time…” Source: RevenueBase Database · checked Sep 20, 2026
12	GPS IT Services LTD	Indirect evidence	Celbridge, IrelandHQ checked Sep 20, 2026	11-50	9 contacts →
	Indirect evidence “Imagine an IT partnership that transcends conventional service providers – one that prioritizes your business growth over short-term gains.” Source: RevenueBase Database · checked Sep 20, 2026
13	Zing Technology	Indirect evidence	Dublin 1, IrelandHQ checked Sep 20, 2026	11-50	9 contacts →
	Indirect evidence “Specialising in financial services and government agencies, Zing Technology transforms your existing software applications into more usable formats.” Source: RevenueBase Database · checked Sep 20, 2026
14	Tetra Technology	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	8 contacts →
	Indirect evidence “Tetra Technology stands at the forefront of the technology services industry, offering innovative solutions that drive business transformation and growth.” Source: RevenueBase Database · checked Sep 20, 2026
15	Dovetail Technologies LTD	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	7 contacts →
	Indirect evidence “Dovetail is a specialist provider of custom IT solutions.” Source: RevenueBase Database · checked Sep 20, 2026
16	Purpledecks	Indirect evidence	Longford, IrelandHQ checked Sep 20, 2026	11-50	6 contacts →
	Indirect evidence “We help Unlock your organisation's potential and bring your vision to life with our comprehensive end-to-end digital services, seamlessly transforming your core technology and…” Source: RevenueBase Database · checked Sep 20, 2026
17	Squarebreed	Indirect evidence	Dublin 10, IrelandHQ checked Sep 20, 2026	1-10	6 contacts →
	Indirect evidence “We are a full-fledged IT Services, Consultancy, Software, web application, Mobile app development company.” Source: RevenueBase Database · checked Sep 20, 2026
18	Move Forward	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	1-10	5 contacts →
	Indirect evidence “We empower businesses to speed up and showcase their digital transformation.” Source: RevenueBase Database · checked Sep 20, 2026
19	Diatom Technologies	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	1-10	5 contacts →
	Indirect evidence “Consulting and delivering organisational transformation programmes and operating services for large portfolios of applications and platforms with a speciality in IT Service…” Source: RevenueBase Database · checked Sep 20, 2026
20	HCS	Indirect evidence	IrelandHQ checked Sep 20, 2026	11-50	4 contacts →
	Indirect evidence “HCS: Your Complete IT Partner for Security, Support, and Transformation Welcome to HCS, your trusted IT partner with over 20 years of experience.” Source: RevenueBase Database · checked Sep 20, 2026
21	Iconnect101	Indirect evidence	Dublin City, IrelandHQ checked Sep 20, 2026	11-50	4 contacts →
	Indirect evidence “iConnect101 Limited helps banks, financial institutions, and enterprises move AI from hype to measurable implementation.” Source: RevenueBase Database · checked Sep 20, 2026
22	Cogo Consulting	Indirect evidence	Kinsale, IrelandHQ checked Sep 20, 2026	1-10	4 contacts →
	Indirect evidence “COGO is an Irish business transformation company with global reach.” Source: RevenueBase Database · checked Sep 20, 2026
23	Webyourmind Limited	Indirect evidence	Dublin 3, IrelandHQ checked Sep 20, 2026	1-10	4 contacts →
	Indirect evidence “We are software development professionals with an unconventional entrepreneurial mindset.” Source: RevenueBase Database · checked Sep 20, 2026
24	Servixon	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	3 contacts →
	Indirect evidence “Servixon builds on the Servixon Technology Platform (STP) – our unified foundation for creating enterprise tech solutions.” Source: RevenueBase Database · checked Sep 20, 2026
25	Dublin Tech Solutions Limited	Indirect evidence	Dublin, IrelandHQ checked Sep 20, 2026	11-50	3 contacts →
	Indirect evidence “Dublin Tech Solutions is an IT consulting firm based in Dublin.” Source: RevenueBase Database · checked Sep 20, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: legacy system modernization companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names legacy system modernization companies.
Partial evidence: Its own public description names part of legacy system modernization companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name legacy system modernization companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 86 legacy system modernization companies based in Ireland

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Legacy system modernization companies based in Ireland at a glance

As of Sep 20, 2026

55.2%Verified-email coverage

46.3Average contacts per company

11-50Median size (employees)

46.5%Largest-city concentration · Dublin

Sep 20, 2026Page data refreshed

Companies by employee count

1-10

11-50

51-200

201-500

1,001-5,000

Email recency for this list is measured worldwide rather than for Ireland, so it is reported there. Company counts and contact totals on this page are exact for Ireland, over 86 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among legacy system modernization companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies: Companies headquartered in Ireland whose own description of what they do matches “legacy system modernization companies”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names legacy system modernization companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among legacy system modernization companies, and records with no verified work email. Companies headquartered outside Ireland are excluded even when they keep an office there.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every listed company carries at least one verified work email, 2,201 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on September 20, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Legacy system modernization companies by metro

Legacy system modernization companies in Dublin40

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names legacy system modernization companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many legacy system modernization companies are there based in Ireland?

RevenueBase identified 86 legacy system modernization companies headquartered in Ireland as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Version 1, headquartered in Dublin, tops this list with the largest team on record.

Which city has the most legacy system modernization companies?

Dublin leads with 40 headquartered companies, followed by Dublin City (3) and Cavan (2).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 2,201 verified decision-maker contacts tracked across these 86 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 20, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.