Seattle’s Madrona Venture Group is leading a $27 million investment in Fauna, a company founded by two former Twitter engineers that is positioning itself as a leader in databases for a new generation of applications. Eric Berg, a former Okta and Apptio executive, is taking the helm of Fauna as CEO, succeeding co-founder Evan Weaver, who is becoming CTO. Bob Muglia, the former Microsoft executive, who was most recently CEO of cloud data warehouse company Snowflake, is joining the 40-person company as executive chairman.