Home Office CTO Denise McDonagh is set to take early retirement after three decades in public IT.

The department will replace the former director of G-Cloud with another CTO as well as creating the new role of chief digital officer (CDO) to help reshape its IT infrastructure.

McDonagh will step down in December, it was revealed yesterday, just a week after she appeared in a recorded webinar to announce plans to overhaul the Home Office’s IT systems.

The project, dubbed Reset4, aims to transform the department’s computer infrastructure by 2020.

McDonagh used the webinar to outline the Home Office’s intention to tender work to SMBs via the G-Cloud, as the department seeks to replace two large IT contracts with Fujitsu and Atos that expire in two years.

She said: "Between now and 2016, we will move away from being locked into massive end-to-end contracts, or tied to particular technologies, to a model in which we have far greater flexibility to change our IT in response to changing needs."

The two new roles are already being advertised, with the Home Office expecting the successful CTO candidate to oversee 1,000 technology professionals and allocate a combined capital and resource budget of £325m.

The new CTO would report to Home Office COO Mike Parsons and would be tasked with cutting dependence on legacy systems, according to the job advert.

It outlined two key responsibilities as: "Ensur[ing] that digitally driven solutions and services are fully supported by the right architectures and systems, and that dependence on existing legacy systems and contracts is dramatically reduced."

The CDO would take on a team of 300 IT digital professionals and have an annual budget of £29m.

The two roles seem to reflect the structure suggested by the Government Digital Service, which has cut the role of CIO from Whitehall. Interviews are earmarked for August and September.

McDonagh has spent 37 years in government IT roles, including overseeing G-Cloud, the cloud procurement framework, after a five-year run as deputy CIO at Defra and serving as head of IT for the Department of Health.

She was awarded a CBE last year for services to government IT.