When you walk into the offices at my startup, there’s something different about the place. You’d be hard-pressed to put your finger on it at first, but if you’ve been to other San Francisco startups, the difference will slowly dawn on you: More than half of our 74 employees are female.

Much has been written on the male-dominated culture of Silicon Valley. The extent of the dominance, though, is perhaps most evident in a few numbers. Women start about 30 percent of businesses around the country, according to a 2009 study by the Center for Women’s Business Research. Yet research by the Startup Genome reveals that only 1 in 10 Silicon Valley startups are founded by women.

This has a trickle-down effect on the number of women who aspire to work for tech companies. The National Center for Women & Information Technology found that the ratio of women studying computer science has dropped from 37 percent in 1985 to only 18 percent in 2010.

Our startup NerdWallet, a company focused on offering price-comparison tools for financial products, never made gender parity a stated part of the hiring mission. How did we buck the trend? It’s been more a by-product of our goal to create the kind of environment we want to work in -- collaborative, supportive and unafraid of innovation.

Related: Young Women Are Earning Almost as Much as Men for First Time Ever

Should companies want to deliberately do what we achieved by accident, however, here’s a reverse-engineered list of the steps that created a strong women’s workforce at NerdWallet.

Make your first hire a woman. Again, we didn’t hire with gender in mind. It just happened that the best candidate for our first employee was female. She set a high bar for the rest to follow and provided a female perspective at the very outset of the company. At one point in our 4-year history, our workforce was as much as two-thirds women.

Had our first employee been male -- joining the two men who founded the company, Tim Chen and myself -- would NerdWallet have become more of a boy’s club, like so many San Francisco startups? I’d like to think not. I’m glad we’ll never know.

Make most of your senior managers female. Many of our most important first hires were female. As a result, five of our company’s six vice presidents are now women.

Related: What This Female CEO Learned About Gender Bias After Pitching 200 VCs

Senior leaders who are women attract others. When we’re interviewing a female candidate who also interviews with a typical tech startup, we’re usually going to win, because they are interviewed by a roomful of women, not a bunch of guys. They can see we have a culture that will not marginalize them. It creates a virtuous circle that ensures we have a strong candidate pool of women knocking on our door.

Consider having a media, marketing or consumer focus. At NerdWallet, we entice consumers to our online tools through strong personal finance advice and studies. That has necessarily put a heavy focus on media and marketing, areas that historically have drawn more professional women than has engineering.

Most San Francisco startups are born by software engineers, a field dominated by men. According to the U.S. Department of Labor, only one in five computer programmers are female. Women hold about a quarter of all jobs in computer-related professions. Unfortunately, as the number of programming jobs rises, the percentage of women in the profession is declining -- down nearly a third, to 25 percent, from its peak in 1991, according to the National Center for Women & Information Technology.

We have found that women coming from outside a programming background can ably transitioned to developing online tools. For example, Christina LaMontagne, our vice president of health and health analyst Napala Pratini came to NerdWallet from the venture capital and medical-research industries, respectively. Yet they ably shepherded the creation of one our price comparison tools, receiving accolades from Kiplinger.

Provide strong internal support. Last year, LaMontagne formed a “Lean In” group, inspired by Facebook chief operating officer Sheryl Sandberg’s book. The group began as female senior executives meeting monthly for dinners and has branched out to include junior staff members to discuss issues related to working in a male-dominated industry.

“There are a small number of women in leadership positions in tech companies. This can be demoralizing for young women,” says LaMontagne.  “Unfortunately, women in Silicon Valley often are keenly aware of their minority status and feel they have to work harder to establish their leadership potential and earn recognition for good work. I think ‘Lean In’ groups can help women feel supported and encouraged to do their best work.”

There is ample evidence that having more female managers builds profits for startups. An analysis of more than 20,000 venture-backed companies, conducted between 1997 and 2011 by Dow Jones VentureSource, found that successful startups were twice as likely to have women in top management roles than unsuccessful companies.

Yet the same survey found that women made up less than 7 percent of senior managers. If the Silicon Valley is going to live up to its meritocratic ideals, that statistic has got to change.

Related: Women Win in the Classroom, Struggle in the Boardroom (Infographic)