The world’s newest capital is a war-damaged city of tin-shack housing and bumpy roads, strung out along the steamy banks of the White Nile river.

"Juba might not look like Washington or London - or even Khartoum, Kampala or Nairobi," said William Deng, a building material trader, referring to South Sudan’s regional neighbours.

"But it’s the capital of our new nation, and I’m proud of that," added Deng, whose shop is in the narrow dirt streets of the city’s Konyo-Konyo market, a key commercial centre.

South Sudan’s capital Juba was left in ruins by decades of conflict, violence that drove its people to vote overwhelming to separate from the north, with formal independence to be declared on Saturday.

"We’re a baby state starting from nothing, but we’ll build it up," Deng said, waving at the bustling street crammed with traders.

Entrepreneurs and jobseekers have poured into Juba in recent years, lured by profits from aid and oil dollars, be they southerners who fled during the war coming home, or neighbours from regional nations.

"Business is good and I can make a profit, I can’t make back home," said Ismail Hussein, a vegetable seller from neighbouring Uganda.

"It’s not easy doing business but there are opportunities here to make good profits," said Kenyan cell phone engineer Wilson Oloo.

Yet it is also a refuge for citizens from nearby countries, offering a new home to those fleeing persecution or conflict.

There are Somali war fugitives, Eritreans escaping an autocratic government and a decades-long compulsory military service, and Congolese forced across the border by rebels.

"The business opportunities are good here, something we’d never have at home," said Robel Abraha, an entrepreneur from Eritrea.

"Juba beats Mogadishu," said Yussuf Siyad, a trader from Somalia's battered capital.

"The profits are good, although it is harder sometimes than I had hoped," he added.

Siyad bought a corner shop formerly run by a northern Sudanese trader, who sold his business to return home fearing violence during the south’s independence referendum in January.

From canvas tents to shipping containers

But there are also many from north Sudan who have stayed, and don’t want to return across what will soon be an international frontier.

"We came here because of the war at home," said Mohammed Nimir from the Darfur region of north Sudan, where the eight-year conflict between rebels and government forces continues, despite Qatari efforts to broker a peace deal.

"I’d like to go back to Darfur someday, but until I know it is safe for my family, Juba is a place where we can earn a living."

Others come from the northern state of Southern Kordofan, where violence in the civil-war-era battleground of the Nuba Mountains broke out again last month, as the northern army sought to crush opposition.

"We don’t feel safe back at home," said Gatar Jabir, a motorbike mechanic from the Nuba, drinking spicy coffee under a shady mango tree.

"I’m staying in the south, until I know that we can go back in peace," he added.

During the war, Juba was a small government garrison town surrounded by rebels. But it has rapidly expanded since then, to become a sprawling city with an estimated population of up to 300,000 people.

Juba still lacks even basic infrastructure, including reliable power, water and sewage systems. But huge improvements have been made since the war ended six years ago.

In the early days, aid workers and diplomats lived in canvas tents. Those have now been upgraded to hotels made from shipping containers.

There is a rapid construction boom. New bridges are being built, and on major routes, tarmac roads have been laid down and street lights erected.

That business has drawn a varied crowd from across the world, from Lebanese traders to Chinese construction companies and US security contractors - as well as a small army of international aid agency or UN workers.

There are even the 'Cuban Jubans' - southerners sent during to the war to Havana for education, who are now coming home.

It remains far from perfect. Traders complain of harassment by security personnel, as well as resentment among southerners, some of whom feel excluded from the lucrative profits of outsiders.

A lack of education is a major restriction - 85 per cent of southerners are illiterate, and even small business opportunities are often taken by foreigners.

But Information Minister Barnaba Marial Benjamin stresses that all are welcome in Juba.

"For many years we in the south were forced outside to Kenya, Ethiopia, Uganda and elsewhere for shelter from the war, and the people there welcomed us," Benjamin said.

"So they are welcome now in our city."