The struggle for Syria's second city Aleppo has been locked in stalemate for months, fuelling the frustration of rebels who see no way out but to doggedly battle on.
"We take a building and then lose it two or three days later, only to take it back the following week," said Abu Ahmad, whose platoon operates in the Salaheddin and Saif al-Dawla districts of the devastated city that was once Syria's commercial capital.
"There is no progress. We are not winning the war," the 42-year-old fighter grumbled as he spoke to an AFP reporter who passed the night with the platoon on the front line.
"Take this street, for example. We took it in just an hour a year ago, and since then we haven't advanced one metre (yard)."
The conflict in Syria has cost more than 115,000 lives since it erupted in March 2011 with peaceful protests that became a civil war after a harsh regime crackdown on dissent.
But the fighting came late to Aleppo.
Rebels seized parts of the northern city in July 2012 and President Bashar al-Assad's troops have been trying ever since to regain full control of it.
Morale is particularly low this night. One of the rebels has been seriously wounded by a sniper who shot him in the chest.
Resting his AK-47 assault rifle against the wall and taking off his combat jacket, one of Abu Ahmad's men said bluntly: "This war is wearing us down.
"The food is bad, and there's not enough of it. We can only wash a couple of times a week because we don't always have water, and the electricity comes and goes."
But it is not just everyday comforts that are lacking, but the means to wage a proper war, said Abu Ahmad, as he opens a plastic bag and empties its contents on the floor.
Two men collect the bullets up and snap them into magazines, which they shove in their jackets.
"We have to count every bullet," Abu Ahmad said.
The daily tedium of battle
"We don't have the luxury of wasting ammunition... If the army attacked now in force, we would only have enough to pull back without losing too many men."
The daily tedium of the battle is relentless.
The men move through the night's shadows, ghost-like shells of buildings on either side. Broken glass crunches under their boots.
Pop! A far-off sniper takes a shot at them, but no one is hit.
They run into a deserted building and up to the fourth floor.
There, through holes in the wall, they aim their Kalashnikovs into total darkness. Waiting for a flicker of light, a sound, a moving shadow.
And then, they make out a small group of men edging stealthily along the street.
They open fire, emptying their magazines into the darkness.
"And that's the way it is, night after night," said one of the fighters, Omar, his voice tinged with bitterness.
"The commanders keep telling us to wait, that they are preparing a plan to take Salaheddin, but all we do is fire through holes in the wall.
"I don't know what they're waiting for. We can't spend five or 10 years peering through holes in the wall and waiting for Allah to win the war for us."
Despite being disillusioned, the rebels see no alternative to carrying on the fight.
"We couldn't surrender because they would show us no mercy, and a political solution wouldn't change anything," Abu Ahmad said.
"No, the only solution must be for Assad to leave."
Hussein, a 23-year-old former student of Arab philology at the University of Aleppo, tries to explain why.
"Assad is discredited in the eyes of the people. How could we do a deal with someone who has massacred his people and now wants to negotiate to stay in power as if nothing had happened?"