Shay Hazan was born on November 22, 1989 and works out of Tel Aviv as a bassist, composer, producer and mixing engineer. He came to music on the electric bass at twelve, playing rock, and moved into jazz through a local conservatory. In 2007 he took up the double bass and went on to study jazz and improvisation at the Jerusalem Academy of Music and Dance. Soon after finishing there he was working in three ongoing groups at once: the New Albert Beger Quartet, the Stephen Horenstein Sextet, and the trio Bones.

Bones, with the Amsterdam-based bass clarinetist Ziv Taubenfeld and drummer Nir Sabag, is where his recorded career starts. The trio's self-titled debut was taped in May 2015 at Niels Brouwer's studio in Amsterdam and issued by Leo Records in February 2016. Haberdashery followed on the same label in September 2017, recorded live at the Bimhuis in Amsterdam on October 1, 2016, and Reptiles came out on the Lithuanian label NoBusiness Records in November 2019, cut at Splendor in Amsterdam on November 14, 2017 and pressed in an edition of 300 LPs. All three are built on Taubenfeld's writing, with Hazan on double bass throughout.

It was at a Bones performance that Hazan first saw William Parker play the guimbri, the three-stringed skin-covered bass lute of Moroccan Gnawa music. He bought one, worked from recordings of the Gnawa master Maleem Mahmoud Guinia, including Guinia's meeting with Pharoah Sanders, and folded the instrument into his own writing rather than trying to play repertoire Gnawa. The guimbri became the signature of everything he has released under his own name since.

His long partnership with the saxophonist Albert Beger, thirty years his senior and his teacher, produced four records. Freedom Is An Option (Jazzis Records 1033) put him in a quartet with pianist Milton Michaeli and drummer Adam Cohen. Black Mynah (Creative Sources CS 473 CD) is a duo, recorded at the Mishkanot Sha'ananim Studio in Jerusalem in January 2017 and issued in a limited edition later that year, with Beger on tenor saxophone and bass clarinet and Hazan on double bass and guimbri; every piece on it is improvised except track two, "Cycles," which Hazan wrote. The Gate (NoBusiness NBLP 126, 2019), billed to the Albert Beger Quartet, was recorded at Alt Studio in Afula on May 31 and June 1, 2017 and pressed as 300 LPs. Cosmic Waves (NoBusiness NBCD 167, 2024) is the quartet with Taubenfeld on bass clarinet and Hamid Drake on drums, taped at Levontin 7 and Kitcha Studios in Tel Aviv in July 2023, and the record where Hazan's guimbri and double bass sit side by side across four long pieces.

Two of his own leader dates appeared in 2018. Good Morning Universe, a 10-inch EP on NoBusiness in an edition of 300, was recorded at Levontin 7 on February 17, 2017 by a six-piece with two tenor saxophones (Beger and Eyal Netzer), two drummers (Haim E. Peskoff and Ofer Bymel) and Nadav Masel on a five-stringed custom cello called the Hamsa; every piece is Hazan's. Domestic Peace, on the New York label OutNow Recordings, introduced the Shay Hazan Quintet: Tal Avraham on trumpet, Netzer on tenor, Michaeli on piano, Peskoff on drums and Hazan on double bass, recorded at Levontin 7 on January 10, 2018 and mastered by Yoni Kretzmer. The same quintet returned in 2021 with the 7-inch single "Beber's Cha Cha" for the London label Jazz45 and the album Nuff Headlines for Chant Records, both drawn from a December 18, 2019 session at Haogen Studios.

From 2021 his output splits into two streams. The free jazz work continues, but the records under his own name moved to the London label Batov Records and to a studio-built music that puts the guimbri against horns, synthesizers and hip hop rhythm. Reclusive Rituals (2021) was assembled from parts recorded at home studios during the 2020 lockdowns, with Avraham, Netzer, Michaeli, Sabag and Doron Segal contributing. Wusul (2024) is bigger and more danceable, with Shahar Haziza and Sabag on drums, Netzer on tenor, Roy Zuzovsky and Avraham on trumpets and Nitai Hershkovits guesting on keyboards; its title is the Arabic word for arrival, chosen for the birth of Hazan's first child. When It Rains It Pours (2025) came out of a period when joint problems stopped him playing double bass and guimbri and pushed him back to the electric bass he had set aside; he plays guitars, synths, bass, guimbri, vocals, percussion and programming on it himself, with guest spots from the Ethiopian-Israeli saxophonist and singer Abate Berihun, Netzer, Zuzovsky, Haziza and Taubenfeld.

Alongside his own catalogue he has been a working sideman and studio hand on the Tel Aviv scene. He plays double bass on the Gal Atzur Trio's 2018 OutNow debut, on the free trio record New Sadness with the American tenor player John Dikeman and Croatian drummer Aleksandar Škorić (Klopotec, 2018, recorded at Zaal100 in Amsterdam on November 9, 2017), on Avocado Fields with alto saxophonist Michaël Attias and Haim Peskoff (self-released, 2019), and on Ziv Taubenfeld's Full Sun (Multikulti Project, 2020), an eight-piece taped at the Bimhuis on January 9, 2019. He appears on three tracks of the clarinetist Harold Rubin's Friends (Jazzis Records, 2022), mixed Rubin's Air Kiss Suite and mastered the Lior Milliger Free Improv Trio's Your Comfort Zone Will Kill You. Outside jazz he produces and plays for Israeli pop and hip hop artists, including the singles "Back to Afrika" with the Ethiopian-Israeli singer Gili Yalo (2023) and a Moroccan-language cover of Kaveret's "Yo Ya" with Haim Uliel (2023).

Hazan is one of the rare bassists who leads from the bottom of the band rather than from a front line, and the writing on his quintet and solo records is built so the bass carries the theme. The three musical sources he names for that music are the free jazz and civil rights era of 1960s Chicago, Moroccan Gnawa, and contemporary hip hop, and the guimbri is what holds them together: a bass instrument with a fixed, hypnotic, repeating function that suits a groove record and a free session equally. His listening runs to Albert Ayler, John Coltrane, Eric Dolphy, Charles Mingus, Sun Ra, David S. Ware, William Parker and Hamid Drake, and the spiritual free jazz strand in that list is the one critics pick out. Writing in the Free Jazz Collective, Eyal Hareuveni located Hazan's music in the spiritual free jazz of the sixties with strong North African Gnawa influence and singled out his ear for the individual voices of his players. As a bandleader he tends to write compact themes and let them stretch: the quintet records run to five and seven pieces, while the free dates with Beger, Dikeman and Bones open out into single tracks past twenty minutes. The Batov trilogy pulls the other way, into short, produced, layered tracks where he plays most of the instruments himself, and When It Rains It Pours moves the centre of gravity from guimbri to electric bass and synthesizer.