What: Shares of zulily (NASDAQ: ZU) rose as much as 21.5% early Thursday, then settled to trade up around 12% as of 2:50 p.m. after the online retailer announced stronger-than-expected second-quarter results.

So what: Quarterly revenue rose 4% year over year to $297.6 million, while adjusted earnings before interest, taxes, depreciation and amortization fell around 1.4% to $14.2 million. That translated to a 30.2% decline in adjusted net income to $8 million, and a 33.3% decline in adjusted net income per diluted share to $0.06.

That might not sound impressive, but analysts were only expecting revenue and earnings of $294 million and $0.04 per share, respectively.

Zulily CEO Darrell Cavens noted revenue and profitability both came in above the midpoints of zulily's previous guidance, as the company continues to effectively manage costs while enjoying the fruits of investments made last year to improve its supply chain operations. He elaborated, "We've made good progress on our marketing strategy and we've materially improved our site experience, merchandising selection and order execution to deliver an incredibly unique customer experience focused on surprise and delight, every day."

Now what: For the current quarter, zulily expects revenue between $300 million to $325 million, and adjusted EBITDA between $5 million and $15 million. Similarly, analysts were anticipating third-quarter revenue of $313.7 million, and earnings of $0.05 per share.

Finally, for the full year 2015, zulily reiterated its forecast for revenue between $1.3 billion and $1.4 billion, and adjusted EBITDA between $55 million and $70 million. Wall Street's models called for 2015 revenue of $1.34 billion, and earnings of $0.26 per share.

In the end, it's encouraging to see zulily gaining ground, especially after it disappointed investors three months ago by saying it would take a hit in the near term by slowing marketing to retool its processes and invest with long-term growth in mind. While I'm personally still happy to watch zulily stock from the sidelines as its initiatives play out, I can't blame the market for bidding up shares today.