By day, Madam Choong Chui Ping teaches mechanical technology at the Institute of Technical Education. By night, the mother of two is a "tailor" who has been sewing masks - not for family or friends, but for strangers she may never meet.
Armed with basic sewing skills and an electronic sewing machine, Madam Choong, 47, has, since the start of this month, been stitching masks for people who have trouble getting surgical masks.
The effort started with about 10 friends who, like her, volunteer at Buddhist charity Tzu Chi Foundation (Singapore) in Pasir Ris.
As more orders from the public came in, they roped in more friends to help and eventually sewed 1,600 masks in less than two weeks.
Half were mailed to members of the public while the rest were distributed to children from two pre-schools in Yishun and senior citizens at two eldercare centres.
The team has since expanded, with more Tzu Chi volunteers on board - about 170 of them.
The volunteers have also joined local apparel firm CYC Tailor to sew masks for migrant workers.
Ms Cara Chiang, marketing manager of CYC Tailor, said it aims to distribute 300,000 cloth masks to migrant workers from this week.
Madam Choong, who has a 15-year-old daughter and 16-year-old son, said: "My friends and I had been talking about cloth masks, but we were not sure if they were effective." Her husband works in the IT sector.
But as soon as the authorities said cloth masks were a form of protection and people were not discouraged from wearing them, the group of friends swung into action and started watching online video tutorials on how to sew masks.
The Government has since made it mandatory to wear masks when outside of the home.
A shop in Chinatown initially gave the volunteers fabric at no cost and they turned it into adjustable masks.
Said Madam Choong: "We should let the front-line healthcare workers have a constant supply of surgical masks, rather than the public trying to fight for the same supply.
"A lot of my friends also couldn't get masks for children, so we thought, why not sew for them?
"At first I was able to sew only 10 to 12 masks each day, but a few days later, I could make 20 masks a day."
The Tzu Chi volunteers have since joined a larger pool of more than 400 volunteers from groups such as Yellow Ribbon Project and the Centre for Domestic Employees, as well as others sourced via Facebook, to help CYC Tailor in its efforts to give masks to migrant workers.
More than 35,000 masks have been sewn and will be distributed to workers through the Migrant Workers' Centre from this week.
CYC pre-cuts the fabric and provides the elastic bands and metal wire for the volunteers.
A group of volunteer drivers collects the masks from the homes of volunteer tailors, who leave the finished masks outside their homes.
Said Ms Chiang: "We've gotten feedback from Yellow Ribbon that the inmates felt really good about being able to do their part for our community of migrant workers, even from prison.
"The masks are really sewn with love, and some of the volunteers have set up chat groups to discuss and exchange sewing tips. It's so encouraging to see how some volunteers even wash and iron the masks after they've finished sewing them.
"We're glad to see so much love and appreciation for the migrant workers who have helped build Singapore."
Madam Choong's sewing routine is from 8pm to 11pm every day.
She said: "It's good that I'm doing this since my family and I can't go out anyway. But I only have time to sew at night because I'm conducting home-based learning during the day for my ITE students.
"So it's a bit tiring for my eyes because my vision isn't that good."
But she hopes her small gesture of sewing masks, one by one, will help migrant workers feel they are not alone.
"Singaporeans were given masks to protect themselves, the migrant workers should also get them."