John Bostock was born January 9, 1954, in Sydney, Australia. He trained at the New South Wales State Conservatorium of Music, studying piano with Evelyn Blanche, composition with Ross Edwards, and jazz piano with pianist Roger Frampton, graduating in 1980 and performing with the Conservatorium Big Band and the John Neeme Ensemble. That same year he appeared on the Contemporary Jazz Ensemble's As Is One (EMI Custom Records), a Sydney Conservatorium student recording directed by Ants Neeme that also carries an early credit for saxophonist Dale Barlow, who went on to a major international career including a stint with Art Blakey's Jazz Messengers. Bostock also recorded as a leader on "Temple Bells" for the various-artists Jazz Action Sessions Vol. 1 (MBS Jazz, 1983) and played keyboards on percussionist Devendran "Dev" Gopalasamy's You're Kidding (recorded 1981, released 1986). In 1983-84 he spent a year in New York, studying contemporary writing and arranging with Don Sebesky and jazz piano with Hal Galper.

Bostock relocated permanently to Israel in 1987, settling for a period at Kibbutz Matsuba. He joined saxophonist Albert Beger's quartet from its founding in 1994, beginning a long-running partnership as the group's pianist and keyboardist. With Beger, bassist Gabi Maier (later billed Gabriel Meir/Gabriel Meyer), and drummer Asaf Sirkis, he appeared at the Israel Festival in Jerusalem (1996) and Jazz at the Red Sea in Eilat (1997), and recorded two studio albums with the group: The Primitive (NMC, 1995), on which he plays piano, and This Life (NMC, 1997; also issued in Europe by Sony), on which he plays keyboards, both credited album-wide on the original release documentation. The same working relationship produced an unreleased 1998 trio session with Sirkis and Meyer, two tracks from which ("Chicken or beef?" and "The ant and the elephant") Bostock issued digitally in 2022 as the EP What Else?, dedicating it to "Albert Beger and my bandmates in those days."

In 1998 Bostock completed a Master of Music, magna cum laude, at the Rubin Academy of Music, Tel Aviv University, studying composition with Leon Schidlowsky, and that year appeared at Tel Aviv's Jazz, Blues and Videotapes Festival. His concert-music career developed in parallel with his jazz playing: he was a finalist in the Israel Philharmonic Orchestra's 1996 60th-anniversary composition competition with "In Memoriam for Symphony Orchestra," became a Represented Composer of the Australian Music Centre in 1997, and won ACUM's "Golden Feather" Prize twice, in 2000 for his String Quartet No. 1 and in 2004 for "When Thou My Love Who." He completed a PhD in composition at the University of Sydney in 2004, studying under Arie Shapira and Anne Boyd, and that same year recorded his first jazz-trio leader album, Journey to Gythia, with bassist Guy Levy and drummer Danny (Dani) Benedikt at Ha'Ogen Studio, self-released on CDr. In 2003 he performed at the Jazz for Peace Festival in Pescara, Italy.

Bostock continued to move between jazz and composed concert music through the 2000s. He guested on piano on the Kadima Collective's White Night Festival release, drawn from a live recording made June 29, 2006, at Tel Aviv's White Night marathon, where he also performed that year alongside Danish avant-garde saxophonist John Tchicai; the same year he led a piano trio with bassist Ora Boazson-Horev and drummer Dani Benedikt at the Tel Aviv Jazz Festival, reviewed warmly by Ha'aretz critic Ben Shalev. Seeing Sky, a self-released collection of solo-piano improvisations recorded over roughly a decade beginning in 1998, followed in 2007-08. His concert works have since been performed by the Israel Contemporary Players, Ensemble Meitar, the Israel Philharmonic Orchestra, the Israel Contemporary String Quartet, the Musica Nova Ensemble, the Arko Symphonic Project, and, in Australia, the Tasmanian Symphony Orchestra.

Bostock's more recent jazz recordings have appeared through his own Bandcamp pages. T.A.Cat (2022), made with guitarist Aharoni Ben-Ari, grew out of a home-recording project during COVID-era isolation in the summer of 2021. Chill About Chill Out followed in 2024, and later that year he returned to the trio format on In Three (recorded live at HaTeiva, Tel Aviv, in August and September 2024), with bassist Gonn Shani and drummer Dani Benedikt.

Bostock's jazz playing sits at the intersection of his two long-running disciplines: a conservatory-trained, harmonically detailed composer's ear and a trio pianist's instinct for swing and interplay. Reviewing Journey to Gythia, critic Adam Baruch drew comparisons to Bill Evans for its "absolute technical brilliance and fluidity" and called it "one of the best Jazz albums ever recorded in Israel," while Ha'aretz's Ben Shalev noted that Bostock draws on roughly five centuries of musical tradition rather than the several decades typical of jazz players, a range audible in Journey to Gythia's arrangement of the 16th-century John Dowland song "Flow My Tears" alongside his own originals. Shalev also praised his ability to be "lyrical, even romantic" without lapsing into cliche, and summarized his output overall as "sketches of feelings and emotions, based on patient observation and profound attentiveness." On Albert Beger's quartet albums, by contrast, Bostock's role was more textural, supplying keyboard color inside Beger's freer, saxophone-led group sound alongside Asaf Sirkis and Gabriel Meyer.