Chapter 26: The Girl in the Lab
Daniel found Yoon Sarah at 2:17 AM on a Wednesday, in the SNU Computer Science building’s basement lab, exactly where he knew she’d be.
He hadn’t planned to go looking for her this early. His strategy had been to wait—let the semester settle, join the right clubs, manufacture organic encounters. But three weeks into his freshman year, he’d already learned that Sarah didn’t join clubs, didn’t attend social events, and didn’t exist in any of the spaces where normal college students could be found. She existed in the basement lab, and the basement lab existed at hours that no healthy human should be awake.
So here he was, at 2:17 AM, carrying two cups of coffee from the vending machine in the engineering building lobby, standing in the doorway of Lab B-204, watching a girl in a hoodie and glasses type at a speed that suggested either genius or a medical condition.
The lab was a windowless rectangle, lit by the blue-white glow of six monitors. Three were showing code—dense, scrolling walls of C++ that Daniel recognized as server-side architecture. Two were displaying data visualizations. The sixth was playing a YouTube video of a cat falling off a table, which was paused at the exact moment of maximum feline indignity.
“That cat is having a worse night than you,” Daniel said from the doorway.
Sarah’s hands froze on the keyboard. She didn’t turn around. “Who are you and why are you in my lab at two in the morning?”
“I’m Daniel Cho. Business Administration, freshman. And it’s not your lab. It’s the university’s lab.”
“It’s my lab between midnight and 6 AM. Everyone knows that.” She still hadn’t turned around. “Business students don’t come to the CS building. You’re either lost or trying to sell me something.”
“I brought coffee.”
“Vending machine coffee?”
“It was the only option at 2 AM.”
“Vending machine coffee is an insult to the concept of beverages.” She finally turned. Yoon Sarah was twenty years old, small, with hair pulled back in a ponytail that had been neat approximately twelve hours ago and was now a topology experiment. Her glasses were slightly crooked. Her hoodie said “Hello World” in monospace font. She looked like she hadn’t slept in two days, which, Daniel knew from his first life, was probably accurate.
She looked at the coffee cups. Looked at Daniel. Back at the coffee.
“Is that the one with the blue button or the green button?”
“Blue.”
“Blue is less terrible.” She took the cup. Sipped. Made a face that suggested “less terrible” was still pretty terrible. “Okay, Daniel Cho, Business Administration, freshman. Why are you here?”
“I want to talk to you about something.”
“At 2 AM.”
“You’re here at 2 AM.”
“I’m always here at 2 AM. That’s different.”
“Why is it different?”
“Because I’m working. You’re visiting. Visitors have regular hours. Workers don’t.” She turned back to her monitors but didn’t resume typing. “You have five minutes. I’m in the middle of debugging a memory leak that’s been haunting me for three days.”
“What kind of memory leak?”
“The kind that makes the server eat RAM like a teenager eats ramyeon. Something in the garbage collector is holding references it shouldn’t be. I’ve traced it to the connection pool but I can’t figure out—” She stopped. Turned back to him. “Why do you know what a memory leak is? You’re a business major.”
Because in my first life, I ran a technology company for twenty years and sat through approximately eight hundred engineering meetings where memory leaks were discussed with the passion and detail of a Shakespeare tragedy.
“I dabble in programming,” Daniel said. “Self-taught. I’m interested in the intersection of technology and business.”
“The intersection of technology and business is where engineers get exploited by people in suits who don’t understand what they’re selling.” Sarah’s voice was sharp, but not hostile—more defensive, like a hedgehog that had been poked too many times. “No offense.”
“Some offense taken, but fair point.” Daniel sat down in the chair next to her—the only other chair in the lab, positioned at a workstation that was clearly unused. “What if I told you I was interested in building something where the engineers aren’t exploited? Where the technology people and the business people are equal partners?”
“I’d say you sound like every tech bro with a pitch deck and a dream.”
“I don’t have a pitch deck.”
“Do you have a dream?”
“I have a plan. Dreams are just plans without deadlines.”
Sarah stared at him. In the blue light of the monitors, her face was all sharp angles and shadows. She looked, Daniel thought, exactly like the person he remembered—the woman who had built Nexus Technologies’ entire technical infrastructure from scratch and had never once accepted a compliment about it without deflecting it to her team.
“That’s the most aggressively Type-A thing anyone has ever said to me,” she said. “And I go to SNU, so the bar is high.”
“I’ll take that as a compliment.”
“It wasn’t one.” She sipped the coffee again. Grimaced again. “Five minutes is almost up. What do you actually want?”
“I want to build a technology company. Not now—in a couple of years. I’m going to need a technical co-founder. Someone who’s brilliant, who cares about the work more than the money, and who can build things that nobody else can build.”
“And you think that’s me.”
“I don’t think. I know.”
“How? You just met me.”
Because in another life, you were the best CTO in Asia. Because you built a cloud platform that served thirty thousand businesses. Because every engineer who ever worked under you said you were the most talented programmer they’d ever met, and also the most annoying, and they meant both as compliments.
“I’ve read your code,” Daniel said. “The open-source server optimization library you published on SourceForge last semester. I found it while researching Korean developers working on distributed systems.”
Sarah’s expression shifted. Not warmth—Sarah didn’t do warmth easily—but a fractional lowering of defenses. The equivalent, in Sarah terms, of opening the door an inch.
“You read my code.”
“I read your code. The connection pooling module is elegant. The way you handle failover is creative. And the comments are—” He paused, remembering the actual comments he’d read in a previous timeline. “Entertaining.”
“My comments are not meant to be entertaining.”
“You wrote ‘TODO: fix this garbage before it ruins someone’s life’ on line 847.”
“That was an accurate assessment of the situation.” But the corner of her mouth had moved. Two millimeters, maybe three. The Sarah equivalent of a belly laugh.
“Look,” Daniel said. “I’m not asking you to commit to anything. I’m asking you to drink terrible vending machine coffee with me and talk about technology. That’s it. If I’m wasting your time, tell me to leave and I’ll leave.”
“You are wasting my time.”
“But?”
“But the memory leak is driving me insane and I need a distraction before I throw this monitor out the window.” She pulled up a chair and pointed at the screen. “Since you claim to know about code, look at this. The connection pool is leaking sockets every time a client disconnects abnormally. I’ve been through the cleanup handler six times and I can’t find where the reference is being held.”
Daniel leaned in. The code on the screen was dense—the kind of tightly-packed C++ that made junior developers weep and senior developers argue about indentation. He scanned it with the practiced eye of a man who had read thousands of code reviews, not as a programmer but as a CEO who believed that understanding the technology was the minimum price of leading a tech company.
“Line 312,” he said, pointing. “The exception handler. You’re catching the disconnect but you’re not releasing the socket descriptor before the catch block exits. The socket stays open in limbo—the garbage collector can’t reach it because the exception handler is holding a reference.”
Sarah leaned in. Read line 312. Read it again. Then she sat back in her chair with the expression of a person who has just been shown something obvious that she’d missed for three days.
“How did you—” She turned to him. “You’re a business major.”
“I told you. I dabble.”
“That’s not dabbling. That’s—” She shook her head. “Who are you?”
“Daniel Cho. Business Administration, freshman. Interested in the intersection of technology and business.”
“That’s your elevator pitch.”
“It’s the truth. Some truths sound like elevator pitches.”
Sarah fixed the bug. It took her thirty seconds—add a socket close call before the catch block, recompile, test. The memory leak disappeared. She stared at the clean output with the specific satisfaction of a programmer watching a three-day nightmare dissolve into a one-line fix.
“I owe you,” she said.
“You owe me nothing. But if you want to pay it forward, have coffee with me again. Same time next week.”
“At 2 AM?”
“You’re going to be here anyway.”
She considered this. Tapped her fingers against the desk—not Soyeon’s three-tap rhythm but a rapid, arrhythmic pattern that suggested a mind that never fully stopped moving.
“Bring better coffee,” she said. “There’s a twenty-four-hour convenience store on the north side of campus. They have canned coffee that’s almost drinkable.”
“Deal.”
“And Daniel?”
“Yeah?”
“If this is a business pitch disguised as a friendship, I’ll know. And I’ll make your life very unpleasant.”
“Noted.”
“Good. Now go away. I have three more bugs to fix before sunrise.”
Daniel left the lab. The corridor was empty, lit by emergency lighting that cast everything in shades of institutional green. His footsteps echoed as he walked toward the exit, and behind him, through the closed door, he could hear Sarah’s keyboard resume its furious rhythm.
Yoon Sarah. CTO of Nexus Technologies in my first life. The woman who built the technical foundation of a four-billion-dollar company. Right now, she’s a twenty-year-old with a ponytail and a grudge against vending machine coffee.
One down. Two to go.
He stepped out into the March night. The SNU campus was dark and quiet, the kind of quiet that exists only in places where thousands of people are sleeping and a few stubborn ones are still awake, building things in basements.
Daniel walked back to his dorm, planning next week’s coffee run and the conversation that would begin the longest, most important partnership of his two lives.