Slack has snagged $427 million in additional funding, at a $7.1 billion valuation, to fuel its effort to become a workplace technology giant.

Dragoneer Investment Group and General Atlantic led the funding, along with others, including investment firm Baillie Gifford, Sands Capital, and previous investors.

With the latest funding, Slack has raised nearly $1.3 billion since it was founded in 2009. Since then, its popularity has grown to over 8 million daily active users with over 70,000 organizations paying to use its chat app.

The company last raised money last September when it said it landed $250 million in funding, with SoftBank’s Vision Fund contributing the bulk of the money.

Although Slack now has a lot of money at its disposal, it faces tough competition from larger companies like Microsoft and Google, both purveyors of enterprise chatting software and related services. Microsoft msft is heavily pushing its Teams chatting app while Google goog is promoting its Hangouts Chat service, part of the search giant’s G Suite lineup of corporate software tools.

In a sign of Slack’s growing popularity, Microsoft recently updated its corporate filings with the Securities and Exchange Commission to list Slack as one of its several competitors along with Apple, Cisco, Facebook, and Google, as tech publication Geekwire noted in early August.

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Slack recently acquired the HipChat and Stride chatting software and related intellectual property rights from workplace software company Atlassian, underscoring the difficultly rival chatting services face against Slack. Slack also bought small enterprise software startup Missions in July for an undisclosed amount; the Missions startup sold a product for non-IT staff to more easily customize Slack to their individual needs.