3 Leadership Lessons From Tumblr's David KarpLearn how the 26-year-old founder navigated the challenges of growing the business in the early days.

In its early days in 2007, blogging platformTumblrwas a two-person operation: founderDavid Karpand lead developer Marco Arment. Now that Tumblr is being acquired by media giant Yahoo Inc. for $1.1 billion in cash, Arment has written a post on his personal blog recalling his memories of working with Karp and of building and growing Tumblr.

"He's a workaholic -- he truly lives and breathes Tumblr," Arment wrote about Karp, who is staying on through the acquisition as Tumblr's chief executive. "I've never even seen him show any desire to work on a side project.David is all Tumblr, all the time."

Arment, who later founded Instapaper, a service that allows users to save articles they see online so they can read them later on, left Tumblr in 2010.

While Karp's management style has been criticized asbeing unpredictable, he led his team in developing a product that has more than 300 million monthly unique visitors and was bought for a huge sum of money. What follows are three lessons on startup leadership, gleaned from Arment's post:

Related:In Yahoo Deal, Tumblr Becomes the Next $1 Billion Startup

1. Find your 'idea editor.'
Entrepreneurs who have big ideas sometimes need to bounce those ideas off someone they can trust. Tumblr was Karp's vision. Although he hired Arment to help with coding and other back-end duties, Karp often used Arment as a sounding board.

"I often served as an idea editor," Arment said. "David would come in with a grand new feature idea, and I'd tell him which parts were infeasible or impossible, which tricky conditions and edge cases we'd need to consider, and which other little niceties and implementation details we should add."

2. Don't try to do everything yourself.
There comes a time for many startups when an entrepreneur simply cannot manage every task on his or her own. Everything from product development to scaling the business to grunt work can simply become too much for one person to handle adequately.

By 2008, Karp's desire to focus solely on product development pushed him to hire a president to handle the business operations. And as the Tumblr team continued to grow, Karp needed to learn how to be a leader.

"David needed to become a product manager, start overseeing a lot more people, and delegate some of the duties he really wanted to keep doing himself," Arment wrote. "After a rough start, David got the hang of being a manager."

3. When leading a team, channel your inner Steve Jobs (or David Karp).
Getting a big startup idea off the ground takes lots of work. Entrepreneurs who hire smart and passionate people, and who inspire those people to exceed their expectations, can increase their chances for success.

At Tumblr, Karp has been ultra-passionate about the product and about the people who use it since the very beginning, according to Arment. He expects his team members to share his enthusiasm and to work hard.

"[Karp] often drove me hard with seemingly impossible demands," Arment wrote. "But David has a lot of Steve Jobs-like qualities, and like many people who worked for Steve, I look back on Tumblr's crunch times with mixed feelings: I don't want to return to that stress level, but David pushed me to do amazing work that I didn't think was possible."

Related:Hyper-Curious and Willing to Fail: How You Can Be More Like Steve Jobs