Paul English remembers when he first started thinking about the issue of homelessness seriously. It was around the year 2000, and he was driving with his son, who was four years old at the time. English, co-founder and CEO of Boston travel startup Lola, said his son had become upset upon seeing a homeless man sleeping under a bridge and asked him about it.

For English, to see a homeless man through the eyes of a four-year-old was a clarifying moment — “it was pretty shocking,” he told me in a recent phone interview — and it helped inform some of the philanthropic work the entrepreneur has done in the past decade or so. That includes the Winter Walk, a two-mile walk organized by English and two friends to raise awareness about Boston’s homeless population that is held its inaugural event on Sunday.

“it was pretty shocking.”

The Boston entrepreneur may be best known as the co-founder and former CTO of Kayak, the travel metasearch website that was acquired by The Priceline for $1.8 billion a few years ago. The spotlight has most recently been on English for his work at Lola, the personal travel app that has now raised $43 million from leading investors, including Google’s venture capital arm, CRV and General Catalyst.

But as “A Truck Full of Money,” the 2016 biography about English, illustrated last year, he’s also been working on many philanthropic initiatives. They were in a large way spurred by the “truck full of money” he made from Kayak’s sale to Priceline and his mentor, the late Thomas White, who has been called “one of Boston’s greatest philanthropists.”

I recently spoke to English in a wide-ranging interview that included his philanthropic efforts, his opposition to Trump and why Lola’s app is making a bit of a pivot.

Supporting the homeless

Like White before him, English said he has a plan in place to donate all of his money, decade by decade, for the rest of his life. In addition to his efforts supporting the homeless, English is also co-founder of Summits Education, a nonprofit that is building schools in Haiti, which has the lowest literacy rate and highest poverty rate in the Western Hemisphere.

When it comes to English’s goal of banishing homelessness, he said has done deeds both small and large. On the one hand, he has donated millions to groups supporting Boston’s homeless population. But he also makes efforts to connect with homeless people on the street personally, sometimes giving them Dunkin’ Donuts gift cards or helping them find a place to sleep for the night. Even just acknowledging them can make a big difference.

“I think the most important thing is to make eye contact because it must be incredibly shameful to be on the street.”

“I think the most important thing is to make eye contact because it must be incredibly shameful to be on the street,” he said. “It must be really kind of robbing you of dignity [for someone not to] acknowledge you.”

However, the real solution to fighting homelessness, English said, is building more housing. In one conversation English recalled with a homeless person, the man had told English that he had bipolar disorder and found shelters to be intimidating when other people around him also have mental illnesses.

Around 500 people showed up for Sunday’s Winter Walk. While it may have fallen a little short of English’s expectations, he told me he would be happy even if some of those who attended became active with one of the advocacy groups the event supported, such as Boston Health Care for the Homeless Program or Bridge Over Troubled Waters.

Fighting Trump

Many tech executives across America have decried President Donald Trump’s immigration and refugee ban, which has currently been put on hold by an appeals court. But English belongs to a smaller group of executives who have fiercely criticized Trump himself and his administration, even calling Trump a “piece of shit” in a tweet from mid-January.

Most recently, English tweeted that he would donate $100 for every retweet, up to $50,000, to the American Civil Liberties Union as penance for his support of the New England Patriots because of the team’s ties with Trump. The tweet from this past Monday has since been retweeted more than 24,000 times, well beyond his goal.

As a CEO of a company that has over 50 employees, English said he feels it’s important to speak out against Trump and thinks that leaders of all type should. He said he would especially like to see more Republicans challenge Trump — something they haven’t done a particularly good job at recently, to say the least.

“It depresses me when I see Republicans fall in line,” English said.

Long before it seemed like Trump’s election victory last November was certain, English had already been an outspoken supporter of refugees, having hosted a fundraiser for and donated tens of thousands of dollars to an organization helping Syrian refugees. The issue of supporting immigrants is an especially sensitive spot for those in the U.S. tech community because of how integral they have been to its growth and success (Steve’s Job’s father, for example, came from Syria).

“I think it’s important that the president is not the only voice,” English said. “I think it’s important for leaders to speak up and say, ‘climate [change] is real, and immigration is real, and it is what has helped build the country.'”

Building Lola 2.0

English’s travel startup, Lola, recently announced it had closed on a $25 million financing round to build the second version of the company’s app, which began last year as an advanced messaging app that connects consumers with a live travel agent.

When I talked to English for the app’s launch last year, he said having a text conversation with a travel agent was a more natural way to book flights and hotels than the self-service options made available at his previous company, Kayak, and others. But in the months since then, English himself has experienced issues with Lola’s conversational approach.

“The good thing about version one is we literally have customers sending us baked cookies and flowers.”

Last September, English said, he was in a situation where he needed to book a flight quickly. He found that it would have taken too long to do that with Lola because of its conversational nature, so he instead opened up Jet Blue’s app and booked a flight within minutes. The situation made him feel “dirty” — “like I cheated on Lola,” he said — but it made him realize the value of having a self-service feature that would let consumers make quick bookings without the help of a travel agent.

While Lola 2.0 will still focus on providing connections to live travel agents, English said it will include a new self-service feature that will diff from what existing travel metasearch sites offer. “Can we do something that’s dramatically different from Kayak and Hotel Tonight?” he said. “That’s what we’re launching in March.”

So far, Lola has only racked up 30,000 downloads on Apple’s Apple Store since it officially launched last May, English said. The app, he admitted, isn’t growing as fast as he had hoped. But he offered the caveat that Lola has done no marketing and just a little bit of public relations at this point — something that will change with the app’s second version.

All that said, English said the company has already earned some loyal fans.

“The good thing about version one is we literally have customers sending us baked cookies and flowers,” he said.