Doomsday Mechanic: My Train Can Be Modified Infinitely

On the fourth day of the train's renovation, the main structure of the planting racks was completed. Six sets of stainless steel frames stood tall inside the carriages, like a forest of steel. Zhang Haitao's welding skills were indeed superb; all the welds were even and full, and no defects were found after penetrant testing. Lin Luo'er was standing on tiptoe checking the level of the top beam, her fingertips lightly touching the cool metal surface. In that instant, she seemed to "feel" the thermal stress at the weld spreading evenly like ripples in water—this wasn't a visual judgment, but a vague, subtle sensation transmitted from her palm.

On the fifth day, the pipeline system was completed. Lin Luo'er personally conducted the first water pressure test. She knelt beside the intricate stainless steel pipes, intently watching the pressure gauge. When the system was pressurized to 0.8 MPa and held for 30 minutes, the pressure drop was less than 0.02 MPa—far exceeding the passing standard of 0.05 MPa—only then did her anxiety truly subside. As she picked up the pen to sign her name on the test report, her fingers trembled slightly from the prolonged tension, but the handwriting was clear and strong.

That same afternoon, the electrical system was installed. Lin Luo'er stood in the center of the carriage, took a deep breath, and pressed the master control switch. The LED array lit up gradually, from dark to bright, the soft white light evenly illuminating each layer of the planting racks, enveloping the entire carriage in an almost sacred halo of tranquility. She adjusted the controller, and the light gradually transitioned from the warm yellow of dawn to the bright cool white of midday, simulating the complete sunrise spectrum.

"So beautiful..." a young temporary worker couldn't help but exclaim softly, his tone full of surprise.

Lin Luo'er didn't respond, only gazing up at the artificial light "farmland" she had created in her hands. A warm current of accomplishment washed away the fatigue of the past few days, but deeper still, there was a strange resonance. She vaguely felt that she could "perceive" the subtle differences in how light energy was being absorbed and reflected by the unplaced cultivation substrate, and even by the air itself. This was too unscientific, she shook her head, attributing it to a hallucination brought on by fatigue and focus.

Unbeknownst to her, at the edge of Wang Zhengyang's quietly unfolding mechanical affinity field, her faint yet unique fluctuations of life energy, like a pebble thrown into a calm lake, caused imperceptible ripples. Wang Zhengyang, who was inspecting the seams of the armor plates in the next carriage, paused almost imperceptibly, his gaze thoughtfully drifting towards the partition wall.

On the morning of the sixth day, the sharp, razor-sharp sunlight slashed through the warehouse windows, carving sharp geometric patterns of light and shadow into the mountains of armor plates. Wang Zhengyang's hand traced the cold steel surface, a mechanical affinity seeping into the metal like an invisible neural network. The feedback was clear and specific: the third plate in the upper left corner had three areas of distorted microcrystalline lattice arrangement, like tiny nodules in muscle; the seventh plate in the lower right corner had an almost imperceptible weak bonding surface at the junction of the back plate and the toughening layer. These defects did not escape his perception.

"Let's install this one first today." He patted the board in the upper left corner, his tone indifferent.

"Why this one?" Chen Yishang happened to walk by carrying a roll of cable, his cuffs stained with black machine oil, but his fingers unconsciously rubbed repeatedly against an old brass ruler clipped to his waist—a heirloom passed down from his master. Wang Zhengyang had long noticed that this old master had an extraordinary affinity for metal tools, as if he could read information simply by touching them.

"The edge cutting angle best matches the starting arc surface on the left side of the front of the car." Wang Zhengyang gave an impeccable technical reason, then wrapped it in a more vague but weighty "intuition," "Moreover, its internal texture is the most uniform, making it suitable as a positioning benchmark."

"Feeling?" Chen Yishang raised an eyebrow, his rough fingertips resting on the cold copper ruler.

"A resonance of experience and data." Wang Zhengyang said without changing his expression, "Following this order, the overall impact resistance can be conservatively increased by more than 10%."

Ten percent. Chen Yishang silently weighed the number. Over the past eighteen days, Wang Zhengyang's seemingly intuitive judgments had always been proven accurate by the results. The old technician finally nodded, a tacit approval of a professional authority that transcended ordinary understanding: "Alright, I'll do as you say."

In the afternoon, in the fourth carriage, Lin Luo'er had changed into a neater dark blue overalls, her long hair tightly coiled behind her head. She was directing the workers to install the second-stage sand filter tank. The carriage was piled high with materials, making the space somewhat cramped.

"Verticality must be guaranteed! I said the error cannot exceed 0.5 degrees!" She held up a laser level, the beam shining on the uprights of the cultivation rack, her small face tense with seriousness. "This isn't ordinary furniture; it has to withstand the acceleration, turns, and bumps of a train!"

When Wang Zhengyang walked in, Lin Luoer was trying to step over a bundle of pipes on the ground to adjust the position of a tank on the opposite side. She slipped, lost her balance, cried out in surprise, and fell backward.

Time seemed to stretch out in an instant. Wang Zhengyang's eyes suddenly focused, his body reacting faster than he thought. He took a step forward, his right hand swiftly reaching behind her to support her. However, the angle and speed at which Lin Luo'er fell exceeded his expectations. His hand did not land on her shoulder or upper arm as he had anticipated, but instead, through her not-so-thick work clothes, it firmly touched an exceptionally soft and full curve—the sensation instantly penetrated the fabric, its weight and elasticity unmistakable.

Both of them froze. The air in the carriage seemed to freeze. Lin Luo'er's cheeks flushed red at a visible speed, even her ears turning crimson. Wang Zhengyang was the first to react, quickly but steadily straightening her up, then letting go, taking a half-step back, his movements so decisive as if nothing had happened, only the lingering warmth of his fingertips reminding him of the momentary lapse in judgment.

"Sorry." His voice was calm and even, as if he had just righted a cargo box. "The floor is cluttered with pipes, watch your step."

Lin Luo'er lowered her head, almost afraid to look at him, her voice barely audible: "...Thank you." She hurriedly straightened her clothes, which had no clear direction, and pointed to a corner with forced composure, "The first-stage sedimentation tank is welded and the sealing test has passed. The sand filter tank should be fully installed today..."

She reported her progress quickly, trying to mask the awkwardness with professionalism. Wang Zhengyang listened calmly, occasionally asking questions, but his gaze lingered for a moment on her unnaturally clasped, slightly trembling fingers. In that brief contact, besides the unexpected softness, he sensed something else—a faint yet extraordinary energy field seemed to exist within her, completely different from the metallic energy fluctuations he was familiar with; it was gentler, full of vitality. Was it an illusion, or…?

That evening, Lin Luo'er returned to her temporary lodgings. The flush on her face had long since subsided, but her mind was still racing. She shook her head and decided to make a video call to her sister, who was far away in France.

The signal connected, and a face that bore a striking resemblance to hers, yet appeared more mature and sophisticated, was projected onto the screen. The background was a simple laboratory office. "Luo'er! Why aren't you resting so late?" Her older sister, Lin Wei, asked with concern. She was a researcher at a classified nuclear materials laboratory of a multinational energy company in Lille, northern France.

"Just finished working on the project." Lin Luo'er rubbed her temples and smiled. "Sis, how's it going on your end? Still struggling with those 'little suns'?" She was referring to the miniaturization project of a new type of nuclear battery that her sister's lab was in charge of.

Lin Wei sighed, rubbing her temples, looking somewhat tired. "Ugh, don't even mention it. The project is under a lot of pressure, and lately the lab management has been acting all mysterious, significantly increasing security levels. The entry and exit checks are incredibly cumbersome. The atmosphere feels a bit...unspeakably tense." She lowered her voice. "Moreover, our access to some of the peripheral data simulation servers has been tightened considerably recently. I heard it's related to some... well, unconventional global environmental early warning assessments received by headquarters. It's making everyone very anxious."

Lin Luo'er's heart sank slightly: "Is it serious? You need to be careful."

"Don't worry, our core research unit has the highest security level. If anything happens, it's probably safer here than outside." Lin Wei smiled and changed the subject, "Tell me, what project are you working so hard on? Last time you said you were involved in a rather unique vehicle modification project?"

"Hmm, it's a very special train renovation project. The boss... is quite impressive, with very high requirements." Lin Luo'er hesitated for a moment, not mentioning Wang Zhengyang's name or specific details. "I'm in charge of the ecological cycle module. By the way, sis, I remember you minored in fluid mechanics and control systems? I encountered a bit of a problem when designing the water and fertilizer cycle..."

The conversation quickly turned to professional matters. The two sisters communicated through the screen, using formulas and terminology, just as they had always done for years. However, while answering questions, Lin Wei occasionally expressed concern about the increasingly tense atmosphere in the laboratory, and repeatedly reminded her sister, "Luo'er, you're all alone in Berlin, so be careful. Lately... I feel like the world is a bit off, all sorts of messy news. Take care of yourself."

After ending the call, Lin Luo'er stared at the darkened screen. Her sister's words, "It feels like something's not right with the world," and the laboratory anomalies she mentioned, vaguely overlapped with the sporadic strange reports she'd gleaned from the news these past few days. She shook her head, banishing the chaotic thoughts, her gaze hardening once more. No matter what, she had to finish building the "ark" she was working on. Perhaps, at some unknown moment, it could truly become a sanctuary—and, if possible, she wanted this ark to one day sail towards Lille.

This idea quietly took root in her heart. But she didn't see that while she was talking to her sister about "laboratory security" and "global early warning," Wang Zhengyang, who was planning a route in the next room, left a very light, almost invisible mark on the location of "Lille, France" on the European map with the tip of his pen.

As night deepened, the arcs of welding in the warehouse continued to flicker. The skeleton of the Longyuan continued to grow, and the unseen threads connecting people, as well as the foreshadowing of the future, were quietly woven into this symphony of steel.