As soon as it was light, Chen Hao squatted down on the open ground to the north and drew lines. He used a broken iron bar as a ruler to draw crooked marks in the mud. Nana stood beside him, holding a level she had salvaged from an old car dashboard.

“If this wall is tilted, a wild boar could knock it down with just one bump,” she said.

"Then don't let it tilt." Chen Hao wiped the sweat from his forehead. "Keep an eye on the height. I'm afraid that as we build, the wall will turn into a slide."

Susan came over carrying a stack of bricks, which thudded as she put them down. She said, panting, "These bricks are no good. Half of them are broken. Even a jigsaw puzzle isn't this hard."

Carl jumped off the cart and shook his sore shoulders: "Didn't we agree last night to start building today? If we keep picking at it, we won't be able to start construction until next year."

“Not choosing will only make things slower.” Nana took a brick, tapped it lightly twice, and listened to the sound to determine if it was hollow inside. “If we use a bad brick, we’ll have to redo everything later.”

Chen Hao stood up and brushed the dust off his pants: "Here's what we'll do: Susan and Nana, divide the bricks first, put the good ones aside and the bad ones at the back. Carl and I will dig out the foundation first. Once you've divided them, we'll lay the base."

The four of them split up to work. Susan and Nana sat in front of a pile of building materials, inspecting each brick one by one. Some bricks looked intact on the surface, but crumbled when tapped. Some were even cracked in half, looking like sandwich cookies when picked up.

"This isn't building materials, it's a waste recycling exhibition." Susan threw a brick that was blackened in the middle into the waste pile.

Nana nodded: "According to standard building codes, the load-bearing capacity of this type of material is less than 30%."

“We don’t even have standard tools,” Susan said with a wry smile. “We don’t even have a decent hammer.”

Chen Hao and Carl had already started digging. Their shovels struck the ground, occasionally hitting loose stones, making their hands numb. Carl changed positions three times, finally kneeling down and pushing forward.

“The soil is too loose,” he said. “Yesterday’s rain turned the bottom into mud.”

"Put some stones down," Chen Hao called out, looking up. "Nana! Any suggestions?"

Nana walked over and took a look: "We need to do some foundation compaction. I suggest mixing gravel and clay in a 3:7 ratio, and compacting it in layers."

"Sounds like cooking," Carl muttered. "Too bad we don't have a pot."

They found some small pebbles and mixed them into the soil. Chen Hao took off his shoes and stepped in to test the hardness; his foot sank halfway in.

“We need to add more,” he said. “Otherwise, the wall will be erected on the first day and flattened out on the second day.”

At midday, when the sun was at its strongest, the first section of the foundation was finally laid. Five meters long, it was barely level. Susan counted the usable bricks and announced, "Only sixty-seven are up to standard, less than half the planned number."

“Let’s build five meters first,” Chen Hao said, “one section at a time.”

Carl carried bricks to the construction site, trip after trip. Sweat dripped down the edge of his hard hat, dripping onto the bricks and being absorbed immediately. After putting down the last brick, he leaned against the wall, panting, "This job is more tiring than when I was working as a laborer carrying refrigerators."

"How many did you move before?" Chen Hao asked.

"At most thirty units a day." Carl wiped his face. "Now, a five-meter wall takes half a day to dry."

“But you had elevators back then,” Chen Hao laughed. “Now, we even have to dig our own ramps.”

The two began building the wall, laying bricks together. Nana measured the bricks, stopping to calibrate every three layers. Susan handed over the materials and recorded the usage of each batch of bricks.

The wall slowly rose. By three o'clock in the afternoon, two-thirds of the five-meter wall was completed. Chen Hao was squatting on the ground patching the cracks when he suddenly heard a "crack" sound.

He looked up and saw a thin crack appear in the corner of the wall on his right.

"The foundation has sunk." Nana immediately went to check. "The left side is higher than the right, by 1.5 centimeters."

"So fast?" Chen Hao reached out and touched the crack. "Only a few hours."

“The load has been added,” Nana said. “The soil underneath wasn’t compacted properly, so it deformed under stress.”

Carl kicked away a pile of broken bricks at his feet: "I told you not to rush to build it up, but you insisted that it was possible."

“It’s no use talking about this now,” Chen Hao stood up. “We need to make amends.”

He had Nana find some thick steel bars and insert them into both sides of the foundation to reinforce it. He then directed Susan to mix cement grout and pour it into the areas where the foundation had sunk. It took them forty minutes to finally stop the tilting.

“We can’t keep rushing like this.” Susan tightened the cap of the cement bag. “We have to wait until each section is completely stable before continuing.”

“The original plan was to make 30 meters a day, but now even 5 meters is a struggle.” Carl sat in the shade drinking water. “At this rate, we’ll all have to switch to a vegetarian diet before the wall is finished—because the wild boars have already emptied the warehouse.”

No one responded.

Chen Hao looked down at the construction drawings; the chalk schedule he had drawn was now smudged with sweat. He redrawn it, changing the daily target from thirty meters to ten meters.

“Revise the plan,” he said. “From now on, each section will be five meters long. Once it’s completed and passes inspection, we’ll move on to the next section. Any section that doesn’t meet the standards will be torn down and rebuilt on the spot.”

“How much more time will that take?” Susan asked.

"It's easier than building it and then having it collapse," Chen Hao said. "We don't have that many materials to waste."

Nana added, "According to calculations, if the phased construction method is adopted, the completion period is expected to be extended by 62%."

"Then let's postpone it." Chen Hao slapped the blueprints on the makeshift wooden table. "Anyway, we don't have any other options right now."

They continued working. The sun was setting, and the shadows were growing longer. Chen Hao called a third halt, discovering that the newly laid section was slightly misaligned again.

“It’s a problem with the soil,” Nana said. “The soil is uneven in texture, so it has to be completely redone.”

"We'll add two hours tonight," Chen Hao said. "We'll use scrapped car lights for illumination, and work for as long as we can."

Carl glanced at him: "Are you really planning to stay up every day?"

"I don't want to stay up." Chen Hao unscrewed a bottle of water. "But if I lie down, I might not even have a place to sleep when I wake up tomorrow morning."

Susan walked over, holding a notebook: "The remaining usable bricks are about forty meters long. If the waste is controlled well, it should be enough to circle the north side."

“The south side hasn’t been counted yet,” Carl said. “The terrain there is lower and the soil is softer.”

"Let's focus on the immediate situation first," Chen Hao said. "With the north sealed off, at least we can get a good night's sleep."

They cleared the foundation again, removing some of the soil that had been filled in the previous day, adding more gravel, and compacting it. Nana used a density meter to measure the density every thirty centimeters to ensure it met the standards.

The headlights were mounted, and two high beams salvaged from an abandoned pickup truck shone on the construction site. The light was dim and yellowish, swaying in the wind.

Susan handed her a glass of hot water: "Have some, don't just give orders."

"I'm not tired." Chen Hao took the cup, his hand trembled, and a little water spilled out, scalding him so much that he shook his hand.

“Your fingers are all blistered,” she said.

"It's nothing." He put his hands in his pockets. "I'll have Nana check if there are any band-aids tomorrow."

Just after eight o'clock, the first five-meter section of the wall was finally completed. It was fairly straight, with consistent height, and no obvious cracks. Nana conducted a final inspection and nodded: "It meets the safety standards for temporary structures."

"It's finally starting to look like something." Chen Hao leaned against the wall, slid down, and finally sat on the ground.

Carl slumped on the wooden plank beside him: "Can I sleep in a little later tomorrow? I feel like my bones are rusting."

"We'll start at nine o'clock," Chen Hao said, "an hour early."

“You actually have the nerve to say that.” Karl closed his eyes.

Susan checked the remaining materials, her brow still furrowed. She said in a low voice, "At this rate, it will take twelve days to seal off the north side. But the weather forecast says it might rain in a week."

"Then let's try to get it done within six days." Chen Hao looked up at the sky. "The waterproof tarpaulin must be put up before it rains."

Nana walked over, holding the updated construction data in her hand: "I suggest increasing the frequency of nighttime operations and optimizing the personnel rotation mechanism."

"Rotation?" Chen Hao smiled wryly. "There are four of us in total. No one feels at ease if anyone takes a break."

They were silent for a moment.

A metallic clanging sound came from afar; it was Carl repairing the cart's axle. He bent over, adjusting the screws little by little with a wrench.

Susan opened her notebook and wrote down the locations of the nodes that needed to be checked tomorrow. Nana stood by the wall, recording the foundation settlement data.

Chen Hao sat on the ground without moving, holding a piece of broken brick in his hand, turning it over and over.

The light shone on his face, casting a long shadow on the ground behind him.

He suddenly said, "Don't you guys feel like we're building a tower of blocks that could collapse at any moment?"

No one answered.

He smiled and threw the broken bricks into the waste pile.

"Never mind, as long as it stands, that's fine," he said. "If it falls down, we can rebuild it."

Carl looked up; the wrench was still in his hand.

What did you say?

Chen Hao didn't turn around.

"I said, keep going."

He stood up, dusted off his trousers, and walked towards the next section of the foundation.