Alex Tumay was only supposed to stay in Atlanta for a week—that was the plan in March. By May, though, producer Metro Boomin was back to calling the music engineer past 3 a.m., telling him to head to the studio, almost as if he forgot Tumay has permanently moved to New York last year. He’s paid rent for his East Village apartment twice since he left—his brother house sits while he’s away—but hasn’t seen the place in two months.

One reason Tumay was in Atlanta was to work on Young Thug’s Easy Breezy Beautiful Thugger Girls, a “singing” album executive produced by Drake. Thug announced his new project on April 26, a Wednesday, saying it will be out later that week. By Friday, Tumay wasn’t in the studio, but at East Atlanta Village craft beer bar Argosy, the wait staff stealing glances at his French bulldog, Gordie. “I hope not,” he said, on whether the project was on schedule, “because I haven’t received the mixes yet.”

To be 30 is to futilely attempt to map out as much of the rest of your life as possible. But while still being a fixture in Atlanta’s oddball hip-hop scene, Tumay can’t bother.

While his credits include Kanye West, Travis Scott, and 21 Savage, he is best known as the rare technician who can keep up with Young Thug. The first time they collaborated four years ago, Thug kicked out six engineers before Tumay helped him knock a song in 10 minutes. He has also done double duty as an executive producer, like when he presented Thug the Southside beat used in 2013 warning signal “Danny Glover,” moments after the 808s were laid.

Tumay was born in Queens, raised in Florida, and after graduating from college in 2010 from Full Sail University with a Bachelor’s in Recording Arts, he moved to Atlanta. Before working full-time in hip-hop, Tumay balanced work at Maze Studios alongside producer Ben Allen (Animal Collective, Youth Lagoon) with the occasional night shift for Bangladesh. He saw musicians learn the rules before they break them—play a guitar part with precision before adding distortion and effects. He thought a compressor could make or break a recording. But at his next job, at Dallas Austin’s DARP Studios, up-and-comers like 18-year-old Metro brought 5-year-old laptops and $200 Guitar Center consoles to work. They’d troubleshoot off what they learned from YouTube. A $700 subwoofer once caught on fire from blaring a TM88 instrumental.

“The most punk-style music being made right now is Atlanta trap,” Tumay says.

Working with that subgenre forever changed his approach to engineering. What may be technically correct, as he learned during his time at Full Sail, doesn’t matter. The end goal is “hi-def street sound.” That can mean optimizing a home recording like Travis $cott’s “Skyfall” for worldwide release, while keeping his original, harshly warped vocals intact. For 21 Savage’s Savage Mode, his “first mixes were way more ambient.” “I wanted to make a straight-up horror movie soundtrack for somebody to rap along with,” he says. “[21] wanted the same thing, just with street elements—the grittiness, rough 808s, heavy kicks. I barely used any compression; nothing was squeezed too tight. It’s ethereal but still in your face.”

Tumay makes his role in music seem straightforward: “I’m a facilitator. I hear what they want and translate it into my terms and make it happen as fast as I can, without slowing things down or ruining anything, making it worse.” But his workload is overwhelming—about eight songs per day in rap, versus one song over several days in rock. He ended up in New York partly to pursue some semblance of a work-life balance. Otherwise in Atlanta, “if somebody wanted me to pull up at 3 a.m., they could knock on my door if they really wanted to.”

Still, he remembers, say, being awake for two days straight, working on Travis $cott’s Rodeo at Seal’s producer’s home in Beverly Hills. Or when he first heard Thug’s quietly unsettling “With That,” which he insisted be included in 2015’s Barter 6. Just as readily, he recalls sessions he missed years ago, like when ​iLoveMakonnen recorded “Tuesday.” “I was dead set on not working that day for any more projects for less than a certain amount,” he says. This year Tumay has worked with rap newcomer Jay IDK and teen singer-songwriter Lontalius. He’s helping with NAV and Metro Boomin’s Perfect Timing, and 21 Savage’s forthcoming album. He’s also linked up with Juicy J and Gucci Mane. How could he say no?

Rich Homie Quan has Justin Childs, who also did “Tuesday.” Future has Seth Firkins. Lil Uzi Vert has K Lee. But an Alex Tumay credit —or a Gordie Tumay credit, like on Big Sean’s “Sacrifices,” under “assistant mix engineer"—actually launches forum threads. When over a hundred Rich Gang tracks leaked in 2015, he came out from behind the scenes to spell out the consequences on Twitter and Reddit: “Now there is a very real chance that these unfinished versions will be the only ones that people ever hear.” Since then, his name has doubled as a co-sign, a stamp of approval. Tumay plans on being even more vocal, so the hard work that goes into Southern hip-hop gets its just due.

“In the future I want to have more of a part in the Recording Academy,” he says. “Metro should have been nominated for Producer of the Year last year. Mike WiLL [Made It], same way. JEFFERY or Savage Mode should have been on Best Rap Album last year. But [the Grammys nominate] producers doing traditional production on traditional records. It’s just too political. There’s too much going on behind the scenes that I don’t like.”

For now, Tumay is at Atlanta’s Patchwerk Studios. It’s a Thursday night, and once again, he recalls how his trip was supposed to go: first a week with Thug, then, another with Nav, at most. Yet, here he and Gordie are with SahBabii, the cherubic-faced “Pull Up Wit Ah Stick” newcomer. Tumay and SahBabii’s older brother, producer T3, are doing a new mix of SahBabii’s S.A.N.D.A.S. Already, though, this mixtape makes sense in a post-JEFFERY world, the music as glittering as his AK is matte.

Tumay also reels over what he saw Thug do the night before: a 24-bar verse where he “sounded like Kendrick [Lamar]” the first half, and “I don’t even know” the second. Dozens of songs have been recorded, then scrapped for EBBTG, an ode to his partner Jerrika Karlae. “I think for [Thug], singing has to do with the romantic element more than the melodic element,” Tumay says, “because he’s always melodic, even in his harder songs. ‘Danny Glover’ has some of the greatest melodies of all time.”

Days later, Gordie has safely returned to New York. But Tumay isn’t home. He is in Toronto, working with a “known artist.” Based on how he says this, covering his phone speaker to confirm he can’t elaborate, he is where he needs to be.