# Shellback (record producer)

Karl Johan Schuster (Swedish pronunciation:; born 1 February 1985), known professionally as Shellback, is a Swedish record producer and songwriter. He was listed as the No. 1 producer of 2012 on Billboard magazine's year end chart, and he also topped the list of their "Top 10 Songwriters Airplay Chart" the same year; he has won four Grammy Awards.
Shellback initially started his career as a heavy metal guitarist before transitioning into pop music production and songwriting.
Shellback regularly collaborates with songwriter Max Martin and together they have produced, written, or co-written songs for various artists such as P!nk, Taylor Swift, Adam Lambert, Britney Spears, Usher, Avril Lavigne, Ariana Grande, Adele and Maroon 5. Shellback has also collaborated with fellow producer Benny Blanco and has produced songs by himself, including "Want U Back" by Cher Lloyd and "Animals" by Maroon 5. He co-wrote and co-produced the song "Can't Stop the Feeling!" along with Martin and Justin Timberlake for the animated film Trolls (2016), earning a nomination for the Academy Award for Best Original Song in 2017.

## Life and career

Karl Johan Schuster was born and raised in Karlshamn, Sweden. He started as a drummer in local indie rock bands in Karlshamn, as well as recording all instruments on the 2003 Meriah demo ...Turn Him Your Other Cheek (a strictly black metal recording), before joining the hardcore-metal scene as a vocalist in 2004 for Blinded Colony, with whom he recorded 2005's Promo Demo and 2006's Bedtime Prayers, drawing comparisons to fellow Swedish melodic death metal band In Flames, before leaving in 2007. In 2005, he also performed as a guest musician on the Faith album Sorg.
At the age of 16, Schuster met Max Martin through a mutual friend. By that time, according to an interview in the Swedish music magazine Stim-magasinet, Schuster's taste in music was "too cool for school" and he had no interest in pop music whatsoever. Julius kept sending Schuster's indie rock-death metal demos to Martin, who became curious about what it would sound like if Schuster were to make pop music. So in 2006 Martin invited Schuster to his studio in Stockholm to record a demo with him, and since 2007 Schuster has been signed to Martin's production company Maratone.
Among the first songs Schuster co-wrote with Martin are Pink's 2008 single "So What" and Britney Spears' 2008 single "If U Seek Amy". In 2012 Schuster won the STIM Platinum guitar prize. In 2014, Schuster produced "Problem" alongside Martin and Ilya. In 2015, Shellback collaborated with Swedish hardcore punk band Refused, as he is both a fan of the band's music and friends with the band's drummer David Sandstrom. Sandstrom sent him the versions of the songs "Elektra" and "366" that Refused had recorded with producer Nick Launay, and Shellback replied with his own arrangements of the two songs. Refused frontman Dennis Lyxzen explained in June 2015 that Shellback's versions were "far more Refused than our versions" and "were better" than the Launay-produced versions. The two songs appear on Refused's comeback album Freedom—"Elektra" was released as a single on 27 April 2015—which was released on the label Epitaph Records on 26 June 2015.

## Discography
### With Meriah

* ...Turn Him Your Other Cheek (Demo) (2003)

### With Blinded Colony

* Promo Demo (2005)
* Bedtime Prayers (2006)

### As a guest musician

* Faith - Sorg (2005)
* Refused - War Music (2019)

## Production discography

| Year | Title | Artist and album | Co-writer | Producer or co-producer |
| 2008 | "If U Seek Amy" | Britney Spears – Circus | Y | |
| 2008 | "I'm Gone I'm Going" | Lesley Roy – Unbeautiful | Y | |
| 2008 | "Boring" | Pink – Funhouse | Y | |
| 2008 | "It's All Your Fault" | Pink – Funhouse | Y | |
| 2008 | "So What" | Pink – Funhouse | Y | |
| 2009 | "Oxygen" | Living Things – Habeas Corpus | Y | Y |
| 2009 | "Bigger" | Backstreet Boys – This Is Us | Y | |
| 2009 | "3" | Britney Spears – The Singles Collection | Y | Y |
| 2009 | "Quitter" | Carrie Underwood – Play On | Y | |
| 2009 | "Friday I'll Be Over U" | Allison Iraheta – Just Like You | Y | Y |
| 2009 | "Just Like You" | Allison Iraheta – Just Like You | Y | Y |
| 2009 | "Outta My Head" | Leona Lewis – Echo | Y | Y |
| 2009 | "Naked" | Leona Lewis – Echo | Y | Y |
| 2009 | "Whataya Want from Me" | Adam Lambert – For Your Entertainment | Y | Y |
| 2009 | "If I Had You" | Adam Lambert – For Your Entertainment | Y | Y |
| 2010 | "Kiss n Tell" | Kesha – Animal | Y | Y |
| 2010 | "Hungover" | Kesha – Animal | Y | Y |
| 2010 | "Party at a Rich Dude's House" | Kesha – Animal | Y | Y |
| 2010 | "Dinosaur" | Kesha – Animal | Y | Y |
| 2010 | "DJ Got Us Fallin' in Love" | Usher – Versus | Y | Y |
| 2010 | "Raise Your Glass" | Pink – Greatest Hits... So Far!!! | Y | Y |
| 2010 | "Fuckin' Perfect" | Pink – Greatest Hits... So Far!!! | Y | Y |
| 2010 | "Time Machine" | Robyn – Body Talk | Y | Y |
| 2011 | "Can't Find Entrance" | Those Dancing Days – Daydreams & Nightmares | Y | Y |
| 2011 | "Loser like Me" | Glee cast – Glee: The Music, Volume 5 | Y | Y |
| 2011 | "Dancing Crazy" | Miranda Cosgrove – High Maintenance | Y | Y |
| 2011 | "I'll Survive You" | BC Jean – Single | Y | Y |
| 2011 | "Back 2 Life" | E-Type – Single | Y | Y |
| 2011 | "What the Hell" | Avril Lavigne – Goodbye Lullaby | Y | Y |
| 2011 | "Wish You Were Here" | Avril Lavigne – Goodbye Lullaby | Y | Y |
| 2011 | "Smile" | Avril Lavigne – Goodbye Lullaby | Y | Y |
| 2011 | "I Love You" | Avril Lavigne – Goodbye Lullaby | Y | Y |
| 2011 | "I Wanna Go" | Britney Spears – Femme Fatale | Y | Y |
| 2011 | "Criminal" | Britney Spears – Femme Fatale | Y | Y |
| 2011 | "Up n' Down" | Britney Spears – Femme Fatale | Y | Y |
| 2011 | "Light Up the World" | Glee cast – Glee: The Music, Volume 6 | Y | Y |
| 2011 | "Moves like Jagger" (feat. Christina Aguilera) | Maroon 5 – Hands All Over | Y | Y |
| 2011 | "Beggin' on Your Knees" | Victorious cast – Victorious | Y | Y |
| 2011 | "No More Secrets" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "Me and You" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "Beautiful People" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "King of Broken Hearts" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "Salvation" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "All That Comes Out of My Mouth" | Carolina Liar – Wild Blessed Freedom | Y | Y |
| 2011 | "Want U Back" | Cher Lloyd – Sticks + Stones | Y | Y |
| 2011 | "With Ur Love" | Cher Lloyd – Sticks + Stones | Y | Y |
| 2011 | "Beautiful People" | Cher Lloyd – Sticks + Stones | Y | Y |
| 2011 | "She Doesn't Mind" | Sean Paul – Tomahawk Technique | Y | Y |
| 2012 | "Payphone" (feat. Wiz Khalifa) | Maroon 5 – Overexposed | Y | Y |
| 2012 | "One More Night" | Maroon 5 – Overexposed | Y | Y |
| 2012 | "Doin' Dirt" | Maroon 5 – Overexposed | Y | Y |
| 2012 | "Scream" | Usher – Looking for Myself | Y | Y |
| 2012 | "We Are Never Ever Getting Back Together" | Taylor Swift – Red | Y | Y |
| 2012 | "I Knew You Were Trouble" | Taylor Swift – Red | Y | Y |
| 2012 | "22" | Taylor Swift – Red | Y | Y |
| 2012 | "Slut Like You" | P!nk – The Truth About Love | Y | Y |
| 2012 | "Your Body" | Christina Aguilera – Lotus | Y | Y |
| 2012 | "Let There Be Love" | Christina Aguilera – Lotus | Y | Y |
| 2012 | "Kiss You" | One Direction – Take Me Home | Y | |
| 2012 | "Heart Attack" | One Direction – Take Me Home | Y | Y |
| 2012 | "Nobody Compares" | One Direction – Take Me Home | Y | Y |
| 2012 | "All That Matters (The Beautiful Life)" | Kesha – Warrior | Y | Y |
| 2013 | "Release You" | Megan & Liz – Look What You Started | Y | Y |
| 2013 | "Easier To Lie" | Cassadee Pope – Frame by Frame | Y | Y |
| 2013 | "On a Roll" | Icona Pop – This Is... Icona Pop | Y | Y |
| 2013 | "That High" (feat. Kelly Rowland) | Pitbull – Meltdown | Y | |
| 2014 | "Air Balloon" | Lily Allen – Sheezus | Y | Y |
| 2014 | "I Wish" (feat. T.I.) | Cher Lloyd – Sorry I'm Late | Y | Y |
| 2014 | "Just Be Mine" | Cher Lloyd – Sorry I'm Late | Y | Y |
| 2014 | "Dirty Love" | Cher Lloyd – Sorry I'm Late | Y | Y |
| 2014 | "Blind Your Love" | Cher Lloyd – Sorry I'm Late | Y | Y |
| 2014 | "Killing It" | Cher Lloyd – Sorry I'm Late | Y | Y |
| 2014 | "I'm in Love" | Ola Svensson – Carelessly Yours | Y | Y |
| 2014 | "Tonight I'm Yours" | Ola Svensson – Carelessly Yours | Y | Y |
| 2014 | "Jackie Kennedy" | Ola Svensson – Carelessly Yours | Y | Y |
| 2014 | "Problem" (feat. Iggy Azalea) | Ariana Grande – My Everything | | Y |
| 2014 | "Animals" | Maroon 5 – V | Y | Y |
| 2014 | "In Your Pocket" | Maroon 5 – V | Y | Y |
| 2014 | "Feelings" | Maroon 5 – V | Y | Y |
| 2014 | "Shoot Love" | Maroon 5 – V | Y | Y |
| 2014 | "Blank Space" | Taylor Swift – 1989 | Y | Y |
| 2014 | "Style" | Taylor Swift – 1989 | Y | Y |
| 2014 | "All You Had to Do Was Stay" | Taylor Swift – 1989 | | Y |
| 2014 | "Shake It Off" | Taylor Swift – 1989 | Y | Y |
| 2014 | "Bad Blood" | Taylor Swift – 1989 | Y | Y |
| 2014 | "Wildest Dreams" | Taylor Swift – 1989 | Y | Y |
| 2014 | "How You Get the Girl" | Taylor Swift – 1989 | Y | Y |
| 2014 | "Wonderland" | Taylor Swift – 1989 | Y | Y |
| 2014 | "New Romantics" | Taylor Swift – 1989 | Y | Y |
| 2014 | "Talking Body" | Tove Lo – Queen of the Clouds | Y | Y |
| 2015 | "Bad Blood" (feat. Kendrick Lamar) | Taylor Swift – Non-album single | Y | Y |
| 2015 | "Elektra" | Refused – Freedom | Y | Y |
| 2015 | "366" | Refused – Freedom | Y | Y |
| 2015 | "This Summer's Gonna Hurt like a Motherfucker" | Maroon 5 – V (reissue) | Y | Y |
| 2015 | "The Original High" | Adam Lambert – The Original High | Y | Y |
| 2015 | "Rumors" (feat. Tove Lo) | Adam Lambert – The Original High | Y | Y |
| 2015 | "Evil in the Night" | Adam Lambert – The Original High | Y | Y |
| 2015 | "Run Away with Me" | Carly Rae Jepsen – Emotion | Y | Y |
| 2015 | "Send My Love (To Your New Lover)" | Adele – 25 | Y | Y |
| 2015 | "Rest Your Love" | The Vamps – Wake Up | Y | Y |
| 2016 | "Just Like Fire" | Pink – Alice Through the Looking Glass | Y | Y |
| 2016 | "Can't Stop the Feeling!" | Justin Timberlake – Trolls: Original Motion Picture Soundtrack | Y | Y |
| 2016 | "Hair Up" | Justin Timberlake – Trolls: Original Motion Picture Soundtrack | Y | Y |
| 2016 | "Still Falling For You" | Ellie Goulding – Bridget Jones's Baby | Y | Y |
| 2017 | "Bon Appétit" (feat. Migos) | Katy Perry – Witness | Y | Y |
| 2017 | "Roulette" | Katy Perry – Witness | Y | Y |
| 2017 | "Revenge" (feat. Eminem) | Pink – Beautiful Trauma | Y | Y |
| 2017 | "Whatever You Want" | Pink – Beautiful Trauma | Y | Y |
| 2017 | "Secrets" | Pink – Beautiful Trauma | Y | Y |
| 2017 | "...Ready for It?" | Taylor Swift – Reputation | Y | Y |
| 2017 | "Gorgeous" | Taylor Swift – Reputation | Y | Y |
| 2017 | "End Game" (feat. Ed Sheeran & Future) | Taylor Swift – Reputation | Y | Y |
| 2017 | "I Did Something Bad" | Taylor Swift – Reputation | Y | Y |
| 2017 | "Don't Blame Me" | Taylor Swift – Reputation | Y | Y |
| 2017 | "Delicate" | Taylor Swift – Reputation | Y | Y |
| 2017 | "So It Goes..." | Taylor Swift – Reputation | Y | Y |
| 2017 | "King of My Heart" | Taylor Swift – Reputation | Y | Y |
| 2017 | "Dancing with Our Hands Tied" | Taylor Swift – Reputation | Y | Y |
| 2018 | "Get Up and Fight" | Muse – Simulation Theory | Y | Y |
| 2019 | "I Don't Care" (with Justin Bieber) | Ed Sheeran – No.6 Collaborations Project | Y | Y |
| 2019 | ''Beautiful People'' (feat. Khalid) | Ed Sheeran – No.6 Collaborations Project | Y | Y |
| 2019 | ''Take Me Back to London'' (feat. Stormzy) | Ed Sheeran – No.6 Collaborations Project | Y | |
| 2019 | ''Remember the Name'' (feat. Eminem and 50 Cent) | Ed Sheeran – No.6 Collaborations Project | Y | Y |
| 2019 | ''Only Human'' | Jonas Brothers – Happiness Begins | Y | Y |
| 2019 | "(Hey Why) Miss You Sometime" | P!nk – Hurts 2B Human | Y | Y |
| 2019 | ''Glad He's Gone'' | Tove Lo – Sunshine Kitty | Y | Y |
| 2020 | ''X'' | Jonas Brothers – XV | Y | Y |
| 2020 | "Diamonds" | Sam Smith – Love Goes | Y | Y |
| 2020 | "Call Me Tonight " | Ava Max – Heaven & Hell | Y | Y |
| 2021 | "Wildest Dreams (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | Y |
| 2021 | "I Knew You Were Trouble (Taylor's Version)" | Taylor Swift – Red (Taylor's Version) | Y | Y |
| 2021 | "22 (Taylor's Version)" | Taylor Swift – Red (Taylor's Version) | Y | Y |
| 2021 | "We Are Never Ever Getting Back Together (Taylor's Version)" | Taylor Swift – Red (Taylor's Version) | Y | Y |
| 2021 | "Message in a Bottle" | Taylor Swift – Red (Taylor's Version) | Y | Y |
| 2021 | "Can I Get It" | Adele – 30 | Y | Y |
| 2023 | "Eyes Closed" | Ed Sheeran – - | Y | Y |
| 2023 | "Blank Space (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "Style (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "Shake It Off (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "Bad Blood (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "How You Get the Girl (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "Wonderland (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "New Romantics (Taylor's Version)" | Taylor Swift – 1989 (Taylor's Version) | Y | |
| 2023 | "Bad Blood (Taylor's Version)" (feat. Kendrick Lamar) | Taylor Swift – 1989 (Taylor's Version) | Y | |

## Awards

Grammy Awards
* Album of the Year - 1989
* Best Pop Vocal Album - 1989
* Album of the Year - 25
* Best Song Written for Visual Media - "Can't Stop the Feeling!"