Sleek desks, casual dress code, free lunch – it's what you'd expect to see in Silicon Valley. But you can also find them in Lagos, Nigeria, where money from U.S. investors is being used to train a new generation of software engineers. Africa is attracting more and more tech startups and in 2017 alone attracted more than half a billion dollars in startup funding.

Hannah Masila is a developer at Andela, one of the continent's top tech startups. She grew up in a rural village in Kenya, where options seemed limited.

"My mind was just revolving around farming and, well, kids were married off as early as 12," she told CBS News' Kylie Atwood. "So it was just like where life will take me I will just go. ... It is shocking like younger me would be like, 'Wow, how did you even do this?' ... I feel for the kids back in the village, like, 'You can do this.'"

Forced to leave her village when ethnic clashes broke out, Hannah went to high school nearby and decided to become an engineer. Until finding Andela online, she was set to become the problem solver at home.

"Fix my dad's TV when it crashes or just help out in the neighborhood. I didn't really think that big," Hannah said.

Seni Sulyman CBS News

Seni Sulyman, the company's president of global operations, recruits talent across Africa. He returned to Lagos after 11 years in the United States, where he attended Harvard Business School and worked at big tech companies.

So why is he back?

"This is the future," Sulyman said. "I think ultimately we are creating an economy in the technology industry which is going to spark a massive revolution on the continent. And I am seeing it happen every day. So the impact we have and the impact I can have as an individual is just so tangible and so meaningful being here. And it's home, so like, who doesn't want to change home!"

In 2016 the company got a $24 million infusion, led by Facebook's Mark Zuckerberg, who followed up with a visit.

"When you have someone who is probably considered the most important person in tech physically standing in your office telling you about how he believes in you, it has a way of just validating everything you are doing," Sulyman said.

The coding done by Andela's developers helps American tech companies innovate from New York to Pittsburgh to San Francisco. With almost 1,000 coders so far, Andela is looking to expand.

"Our idea is that we started in 2014 and we said in 10 years we would have helped to empower 100,000 developers in Africa which takes us to 2024," he said.

Facebook CEO Mark Zuckerberg at Andela's offices.

In that same amount of time there is projected to be a shortage of almost one million developers in the U.S. domestically. So American companies are going to be looking. Competition for a job at Andela is fierce. Its acceptance rate of applicants is about .7 percent – less than one percent. For some perspective, Harvard's acceptance rate is higher.

Changing conceptions about what a coder looks like and where they come from is igniting enthusiasm and Hannah Masila wants her story to inspire younger African generations.

"It doesn't have to be programming but just believing in yourself."

