You might overlook the tiny ridges on the "F" and "J" keys of your computer keyboard, or the tiny dot that appears on number five of a remote control and keypad phones, but those mean the world to Moses Nyongesa.
The 53-year-old uses those keyboard ridges to conduct his daily duties as a senior engineer at Kenya Power's headquarters in Nairobi.
He was employed by the electricity distributor in 1991 when his sight was intact. Things changed in 2004 when he had an accident on Outering Road while driving home from a late assignment in Mlolongo.
The impact damaged his optical nerves and his sight deteriorated gradually. One morning he woke up and it was total darkness. It has been dark since.
It is Monday afternoon when we catch up with him in his office at Stima Plaza, Ngara. He is in the department that handles customers' follow-ups. If Kenya Power technicians fix a problem but it recurs, you are likely to be referred to Nyongesa if you call the headquarters.
He will take your call (he says he calmly lets the angry ones rant all they can because they'll finally calm down) then share the details with a team under him to address the issue.
We watch as he sends a demonstration email to someone in Kenya Power's communication team. This he does with ease, using software that voices every key he presses on his laptop.
Then he shows us how he makes calls from his desk phone. The tiny dot on "5" does the trick. As soon as he feels it, he knows his way around the keyboard and can dial any number.
He also shows us how he makes calls using his touch-screen smartphone, thanks to software that talks back on every action he takes.
And using his cane, he can walk from his desk to the toilets, more than 70 feet away, on his own. He can also walk down the stairs to the parking lot.
Basically, Nyongesa, now blind for 16 years, is comfortable at a workplace for employees without handicaps.
But it has not always been this smooth. In the days after he lost his eyesight, he was a disillusioned man.
"There was a time I almost committed suicide," he says. "You find yourself in a strange world; total darkness."
Here he was, blind at 38, with an eight-year-old daughter and a five-year-old son who could not understand why their father suddenly could not see.
Here he was, a man who was fast rising through the ranks at Kenya Power, having obtained his electrical engineer's degree from the University of Nairobi in 1990.
By 2004 he was an assistant distribution engineer in the Nairobi South region. Now all that seemed like a closed chapter.
Nyongesa is thankful for two decisions his employer made. One was to allow him time to cope with the situation and facilitate his training.
The second was not to dismiss him but to give him an assistant, paid by Kenya Power. The assistant drives Nyongesa to and from work every day.
The training happened at the Kenya Society for the Blind in Nairobi West.
"I went there, shared my story with the project director who then got me to join CAT - Centre for Adaptive Technologies - where you are rehabilitated to start functioning normally. You're trained through multiple applications, then you're also trained through motoring, that is, how you can walk around independently," Nyongesa says.
"At the same time, you meet people who are in this state but are very, very positive. There is (Henry) Wanyoike, that marathon champion. There are professionals who are working in this state," he adds.
The training boosted his confidence and gave him the resolve to push on. If anything, he always thought of his children who depended on him and decided that giving up was not an option.
Back at his workplace, he was provided with software called Jobs Access with Speech (Jaws), the one that powers his laptop.
"That's an app that enables you to communicate normally like anybody else. You can do what you want, like anybody else," he says.
Nyongesa was moved to his current base in 2016, and while there he has been involved in a number of projects, including the installation of CCTV cameras at various places in Nairobi and Mombasa.
He was the company's employee of the year in 2017, bagging a Sh20,000 cheque in the process.
Today, Nyongesa is an executive member of the Society of Professionals with Visual Disability (Sopvid).
"That's a support group for professionals who have eyesight issues. It's a group that has actually been of immense support to me," he says.
He has come to accept his situation and can afford to give advice to whoever might lose sight at their prime.
"It is not the end of the road. It's just a phase of life. You just have to be positive," says Nyongesa.
"Never say it is not possible until you try it, because who says it's not possible? It's your mind. Try it and fail, then say, 'Fine, I did try'. That's where I am."