Gideok Moon (문기덕) is a South Korean drummer and improviser, born in Seoul in 1996 (MusicBrainz gives the date as March 12) and now based in Bern, Switzerland. His own site describes a drummer who works in the space between acoustic and electronic sound, rooted in jazz and widened by free improvisation. He has made one solo album, Alla Prima (Mung Music, 2022), co-leads the duo Life and Sound, whose live album Mealworm appeared in 2025, and is the drummer on Seongmin Ahn's The Lake (2023). He is billed Gideok Moon on the covers of those records, on streaming services and on Discogs; the Jarasum Jazz Festival's pages print the name in Korean order as Moon Gideok.

In Seoul he took a Bachelor of Music in Post-Modern Music at Kyung Hee University, where his own biography says he trained in jazz drumming; the CD listing for The Lake carries the same degree and says he and the other three players had worked together since their university days. He became active in Korea's free-improvisation scene and describes himself as a founding member of MoIM, a Seoul collective of improvisers. The collective's own release notes say it was founded in 2024 by Jiyun Song and Taekjoon Kim and meets monthly, so he is better described as an early participant than as its founder. He is credited on its first compilation, Galpi (Mung Music, July 23, 2025), in a duo track with the saxophonist Sangbeom Kim, and his site lists a MoIM concert with the sound-art group Liquid Sound at the Oil Tank Culture Park in Seoul on November 20 and 21, 2024.

The relationship that shaped his first record was with the saxophonist Sunjae Lee, whose Seoul label Mung Music issues improvised and original music recorded mostly on a vintage Tascam 424 cassette four-track. Alla Prima came out there on September 8, 2022: seven drum improvisations recorded to cassette at Stellive in Seoul in the summer of 2022, with Lee credited for the recording, mixing, mastering and artwork. The seven pieces run 32 minutes 48 seconds, under the titles "End and Start" (끝과 시작), "Double" (더블), "Stone" (돌멩이), "Maybe Tomorrow" (아마도), "Beyond the Winter" (겨울을뛰어넘어), "Once Broken, It Becomes Harder" (부서지고나면 더 단단해진다) and "the REAL". In the album's liner text he says the title comes from the painting technique of finishing a canvas in one sitting with no sketch underneath, that he drew on the Fluxus movement's disregard for the borders between art forms, and that he improvised on the feelings left by particular books, among them Milan Kundera's The Unbearable Lightness of Being. Discogs files it under Free Improvisation and Free Jazz, and a video for "Maybe Tomorrow" is on his YouTube channel.

Life and Sound is his duo with Sangbeom Kim, a drums and saxophone pairing that his site describes as re-identifying the trivial and overlooked moments of daily life, moving across textures from subtone to chaos. A concert billed Life and Sound Vol. 1: "Again, Being" took place at the Yeonhui Art Theater in Seoul on October 1, 2023. Mealworm (2025) is a live album of eight untitled pieces, named on streaming services only by their start times in the recording (00'00'' to 41'36''), which run about 49 minutes in all; Apple Music dates it May 2, 2025 and gives the copyright to Sori-e Naite Music Company, the same company that distributed The Lake. The guitarist Seongmin Ahn is listed in the CD biography of The Lake as a guitarist who took part in Life and Sound.

Much of his Seoul work was as a sideman. On The Lake, Seongmin Ahn's nine-track quartet album made through the Jarasum Jazz Festival's Searching for Jazzmen programme, the cover prints his name beside those of the saxophonist Kim Sangbeom and the bassist Hong Seungmin, and the quartet played the festival's showcase on October 9, 2023; the festival's text calls him a drummer skilled at calm, restrained playing and at drawing on a variety of sound sources. The biography printed with that CD also lists a single by the guitarist Kim Tae-guk titled "윤회" (Yunhoe), the EP Kind Warmth (다정한 온기) by Seo Bo-kyung, a 2021 Jazz Korea Festival appearance in Germany with the Yi Yunseon Trio, and the Hanseong Kang album Go for Launch. His site adds the Yoonhwa Choi Trio's SOund RE;search LAB (2024) and lists dates at Seoul clubs and venues including Club Evans, Dotolim and Mudaeruk between 2024 and 2026. A concert with the saxophonist Sunjae Lee, the saxophonist Sangbeom Kim and the drummer Junyoung Song, billed Double Duo, took place at Mudaeruk on July 29, 2025.

In Bern he is studying for a Master of Arts in Music Performance (Jazz and Contemporary Music) at the Bern University of the Arts (HKB), by his own account. His site lists him in a concert of the music of Alice Coltrane at HKB on September 29, 2025, and Marians Jazzroom's Jazzzelt series, which presents HKB jazz students, listed him as the drummer of the quartet In Walked Indigo (trumpeter Louis Waeber, pianist Anton Martinez, bassist Benjamin Jaton) for March 31 to April 4, 2026, during the BernJazzfest. He works there in two groups: the trio i!i!o, formed with the vocalist Jessie Chen and Tobias Rüetschi, who plays a no-input mixing board (a mixer whose outputs are patched back into its inputs so that it generates feedback), and the quartet EDGE with Lukas Mohl, Nil Flückiger and Mattia Facchini, which he describes as working the border between written material and open improvisation. He has also played in Berlin, at Cocoon on July 3, 2026.

His solo work is Ieum (이음), a Korean word that can mean both "different sounds" and "connection". In it a resonance speaker rests on the drumhead and sends electronic sound through the head, the shell and the snare wires, so that the sound comes from the drum itself and no microphones, mixer or external speakers are needed; the electronic parts are Pure Data patches he builds himself and runs as phone apps. By his own account he first played the setup at Mudaeruk in Seoul in August 2026, and a filmed solo set from Mudaeruk is on his YouTube channel. He was back in Seoul for several dates that month, and his site lists further concerts still to come: i!i!o at Dotolim in Seoul on December 23, 2026, and in Bern on January 24, 2027, and a Colin Vallon and Patrice Moret project at PROZESS in Bern on January 28, 2027, during the PLAYTIME Festival.

Nationality is South Korean on the evidence of birth in Seoul and a Korean career: a Korean university degree, a first album on a Seoul label, and dated concerts and recordings in the Seoul improvised-music scene from 2021 to 2025 before his move to Switzerland. No source states his citizenship, and his Korean base and Swiss base are both current, since his site gives it as Bern and Seoul.

His own text puts the work between acoustic and electronic sound and between the familiar and the unfamiliar, with jazz as the root and free improvisation as the extension. Alla Prima is solo, single-take drumming shaped by the alla prima painting method and by Fluxus; Mealworm is a live saxophone and drums dialogue; Ieum makes the drum itself the loudspeaker; i!i!o hands the drums, voice and a feedback mixer to each other in real time and treats the result as something between composition and improvisation. The sources do not name teachers or favourite drummers, and none are asserted here.