Joe Siller

It is with great sadness that we announce the passing of Joe Siller, age 95, on July 30, 2025. He departed this life peacefully at his home surrounded by his loving wife, Emma and their devoted children.

Joe was born September 2, 1929 in San Antonio, Texas to Sabas and Manuela Siller. He was one of six siblings. A graduate of St Mary's University with a B.S. degree in Physics and Mathematics, he joined the civil service and was a proud veteran with the rank of First Lieutenant.

He first worked in Biloxi, Mississippi at Keesler Air Force Base. In the early days of the space program he worked in Huntsville, Alabama at Red Stone Arsenal, then in Washington, DC as a civil servant, he was invited to speak at the Hague in the Netherlands. In 1962 Joe moved his growing family back to Texas and worked at NASA in Clear Lake as a Systems Analyst for IBM. A brilliant computer programmer, he was part of the team that put the first man on the moon. Joe was one of the foremost developers using the APL computer programming language, ultimately inventing his own interactive program called APDT. He also taught Engineering at the University of Houston Main Campus.

He is survived by Emma Siller née Rodriguez, his wife of 73 years, his daughter Sylvia Salinas and her son Ariel, his daughter Laura Siller and her wife Rebecca, his son Michael and his husband Larry, his daughter Roxanne and her husband Justin, along with their daughter Blythe and her husband Matthew.

They all lovingly remember vacations to California, Colorado and New York, road trips to San Antonio, trips to the library every Monday night and to the beach in Galveston, hikes in Memorial Park, swimming, and walking in the rain. He, and his wry sense of humor, will be greatly missed.

He is also survived by his sister Teresa and many nephews, nieces and in-laws in a large extended family.

There will be a service at American Heritage Funeral Home on August 22, 2025 at 11:00 am and internment at Houston National Cemetery at 12:30pm. In lieu of flowers you may donate to AmericanBrainFoundation.org.