Conway is the son of legendary Silicon Valley angel investor Ron Conway, and was the first outside employee hired by Andreessen Horowitz after raising its inaugural fund in 2009. He headed up the firm’s seed-stage investing program, where he was credited with making the original introduction to Instagram — a mobile photo-sharing app that later was acquired for $1 billion by Facebook (FB). Overall, Andreessen Horowitz has made around 160 seed investments, although the rapid pace has slowed a bit in recent months.

“We’re thrilled for Ronny,” said an Andreessen Horowitz spokeswoman. “He’s really done a great job for us here.”

Conway previously worked at Google (GOOG), which was where he first met Instagram co-founder Kevin Systrom. His original role was in business development, including on such projects as Gmail and Google Calendar. He later moved on to Google Ventures, where he worked as an associate on both fund formation and deal-sourcing.

Sources familiar with the situation say that Conway currently is working alone on the new platform, which is designed to help alleviate the “Series A crunch” for angel-backed companies. He had not yet formally begun fundraising, but expectations are that he’ll be seeking at least $30 million. Unclear if he plans to target institutional investors, or instead focus mostly on Silicon Valley friends and family.

Conway declined to comment for this story, except to confirm that he is leaving Andreessen Horowitz.

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