Mary Coombs

She married John Coombs, a co-worker at LEO. The couple had a daughter, Anne, who became disabled as a toddler and died at the age of six. They adopted three children, Andrew, Paul and Gillian. John Coombs predeceased her in 2012. Coombs died on 28 February 2022, at the age of 93, survived by her three children, three grandchildren, and her sister, Ruth.

In 1969, when she realised that she would not be able to work full-time, Coombs left the LEO team and briefly worked for Freelance Programmers, a company founded by Stephanie Shirley. After three years at home looking after her children, she returned to work, firstly as a primary school teacher in a private school and then – following a year working for a post-graduate Certificate in Education – about 10 years in primary schools in Buckinghamshire. In retirement, she taught piano, and ran the church choir.

Coombs was transferred to English Electric Leo Computers in 1963, a company jointly created by the merger of J. Lyons and Co. and English Electric. In 1968, she was transferred to International Computers Limited (ICL) when they bought out English Electric Leo Computers. In 1964, because of family commitments, she moved from working full-time to part-time. She continued to work in the computing field, mainly editing manuals. She briefly taught a computer programming course at Princess Marina Centre at Seer Green for disabled residents.

After gaining her degree, Coombs spent a year teaching English in Lausanne, Switzerland. Returning home in 1952, she began work at J. Lyons and Co. as a temporary clerical worker, a job she reluctantly accepted while searching for a better alternative. Coombs' mathematical skills soon allowed her to transfer from the Ice Cream Sales department to the Statistical Office, where she heard that the division working on LEO computers had been looking to hire additional programmers.

Once Coombs began officially working with LEO in 1952, she was taught how to program by John Grover, one of the first LEO programmers. Initially, she was the only woman on the team and worked alongside Leo Fantl, John Grover, and Derek Hemy, using LEO to automatically calculate payroll for employees at J. Lyons and Co. The team later did payroll work for the Ford Motor Company using LEO. Coombs also worked on programs for early LEO customers such as the Met Office, the British Army and the Inland Revenue. Coombs is recognised as the first woman to work on a commercial computer.

Mary Clare Coombs (née Blood, 4 February 1929 – 28 February 2022) was a British computer programmer and schoolteacher. Employed in 1952 as the first female programmer to work on the LEO computers, she is recognised as the first female commercial programmer. The National Museum of Computing documents her contribution.