https://www.bbc.com/news/world-asia-india-56912977
The country's very own Serum Institute of India (SII), the world's largest vaccine maker, was meant to supply most of the jabs as the country headed towards an ambitious target - covering 250 million people by July.
As part of a World Health Organization (WHO)-led scheme, India even exported vaccines to countries that needed them.
But three months on, Covid cases and deaths are spiking across the country. Only about 26 million people have been fully vaccinated out of a population of 1.4 billion, and about 124 million have received a single dose. Prime Minister Narendra Modi's government has cancelled exports, reneging on international commitments. Worse, vaccine stocks in the country have nearly dried up, and no-one is sure when more will arrive.
124 million are allowed by August in a country of what was 1.4 billion.
On Wednesday afternoon local time - just as millions of Indians were trying to register online for a Covid jab - the vaccine portal and its accompanying apps crashed.
Starting 1 May, India is opening up vaccination for roughly 600 million more people, to cover 18-44 year olds. But CoWin, as the platform is known, couldn't handle it.
"I am stuck in an OTP loop of horrors," said one 33-year-old while trying to register for her jab. OTPs, or one-time passwords sent to mobile numbers, are a favoured Indian way of verifying identity online. She had a string of messages with OTPs, but nowhere to put them.
Others didn't even get that far - #WaitingForOTP was soon trending on Twitter, and the memes and jokes followed. Eventually the site was back up - but, to the disappointment of more than 13 million people who did finally register, not a single vaccine centre had slots for booking.