Amanda Tester Snyder is known for her paintings of birds, clowns, dolls, still life, houses, and barns as well as for her abstract compositions. Her works—which combine strong forms, vigorous brushwork, and rich color—align her with other early modern painters in Oregon, including her friends C.S. Price and Charles Heaney.

Amanda Tester was born near Mountain City, Tennessee, the oldest of the five children of William Jefferson Tester and Della Lee Hull Tester. When she was nine, the family moved to Roseburg, Oregon. In grade school, she showed aptitude for art, as did her younger brother Jefferson Tester (1899-1972), who also became an artist.

In 1916, Amanda married Edmund Snyder, an Aurora Colony descendant. They settled in Portland, where their son Eugene was born in 1918. She took classes at the Portland Museum Art School in 1917 and studied with Sidney Bell, a portrait painter from England, in 1925. Otherwise, she was self-taught, developing variations of Impressionism and Expressionism as she worked in relative isolation in the basement of her Portland home. She also made blockprints, sculptures, pottery, and collages. During her life, she exhibited in thirty-two solo and numerous group exhibitions.

Snyder's works are owned by the Oregon Historical Society, Portland Art Museum, Seattle Art Museum, Reed College, Jordan Schnitzer Museum of Art, Hallie Ford Museum of Art, and corporate and private collectors.