Leonid N. Gruman, of Sudbury, MA, passed away on September 24, 2026 at age 87 surrounded by immediate family.

Born in Sevastopol, USSR, on August 25, 1939, he was the son of the late Natan Gruman and late Etya Grinberg.

When Leonid was 2, he fled his home region of Crimea from the advancing Nazi troops with his mother, older brother and paternal grandparents, while his father remained to fight the enemy as part of the Soviet Naval Command. The family found themselves in Siberia, and Leonid’s memories of that chaotic time were of trains and farm animals.

After the war ended, the family reunited in Sevastopol, where Leonid started school. In second grade, when an intense flu confined him to home and bed for about a month, in order to fight boredom, Leonid started reading the daily newspaper. A mediocre student before his illness, he came back to school reading so well that his teacher frequently tasked him with reading out loud to his class when she wanted a short break. Eventually, Leonid graduated from school as a gold medal recipient, awarded to students with perfect GPA.

In 1956, Leonid moved to Leningrad to study Electrical Engineering at the Leningrad Electronic Technical Institute: a new field at the time at the cutting edge of technological progress. After graduation, he began his career on a space research project at a closed facility near Moscow. He continued his career at an R&D lab in Leningrad, designing pioneering electronic devices. He was instrumental, not only in developing technologically advanced new products such as digital scales and calculators, but also in organizing the production resources to bring them to consumers. He won multiple awards of excellence for the products developed by him and his teams.

After moving to the US, Leonid continued his career as a circuit designer and tester at various electronics companies in Minnesota, Texas, and Boston, while developing commercial thermostats, cellular signal transmitters and receivers, among other projects.

Upon wrapping up his engineering career, he transitioned to working full-time as a grandpa, helping take care of his grandchildren Jacob, Lia, Daniel and Maxwell.

Leonid was a devoted husband to Zinaida, with whom he recently celebrated their 52-year wedding anniversary. Above all else in life, Leonid treasured his family. He was an intelligent, witty, charming, kind, generous man of strong spirit and keen interest in politics and sports (with American basketball having a special place in his heart). He read widely, quickly and with pleasure - much like he did all the things he took up.

Leonid was also proud of his Jewish heritage, even and especially at times when it was unwise or even dangerous to exhibit it. He instilled this pride in his children and grandchildren, showing by example what it means to be true to oneself under all circumstances.

Leonid was predeceased by his parents and older brother Saveliy. He is survived by his wife, Zinaida; his son, Mark, and his wife, Megan, along with their children, Daniel and Maxwell; his daughter, Sofya, and her husband Leon, along with their children, Jacob and Lia, and by his cherished nephew Dmitriy and his family.

Leonid will be laid to rest during a private burial service at Mount Pleasant Cemetery in Sudbury. Friends and Family are invited to join Leonid's Celebration of Life on Sunday, October 4th, from 6:30pm to 8:30pm in the Functional Hall of the Pompositticut Community Center in Stow, MA; in keeping with Jewish tradition, attendees are welcome to bring a small dish that they feel would bring comfort to the occasion.

In lieu of flowers, contributions in his memory may be made to Good Shepherd Community Care.

Arrangements have been entrusted to Dee Funeral Home & Cremation Service of Concord.