Companies like Slack and Asana stormed into the world of tech to steal a march on incumbents like Microsoft in providing a new wave of point solutions to make it easier for workers respectively to chat with each other, plan projects and more. Now another startup is announcing a massive round of funding for a platform that it believes has its own unique role to play in disrupting enterprise IT: by providing a single, all-in-one solution covering various aspects of workplace productivity.

ClickUp, which provides set of tools that lets its users tackle project management, document collaboration, spreadsheets, chat, and goals from a single platform — a little like Workday but for productivity — has raised $400 million, a Series C funding that the company confirmed values it at $4 billion post-money.

ClickUp said that this is, to date, the single-largest Series C in the workplace productivity market (others like Slack have raised bigger single rounds… so still room to grow!). Andreessen Horowitz and Tiger Global are co-leading the round, with Lightspeed Venture Partners and Meritech Capital Partners also participating. Craft Ventures and Georgian Partners are among its earlier backers; the company has now raised $535 million.

ClickUp — based out of San Diego — plans to use the funding to double down on growth in Europe, with 600 new jobs and a new HQ set for Ireland that will handle R&D, operations and sales. The company counts the likes of Google (yes, the company behind its own productivity tools), McDonalds, Booking.com, and Netflix among its large enterprise customers. In all, ClickUp is being used by 800,000 teams — up from just 200,000 a year ago.

A significant proportion of ClickUp’s customers, some 40%, are already based outside of the U.S, with a large part of those users in Europe — some 275,000 teams in all, the company said — hence its interest in focusing more deeply in the region. It will also include localised versions of its platform for France, Germany and Spain, the company said.

The shift to cloud services and a rising appetite from knowledge workers to use tools in the office that work just as intuitively as their “fun” consumer mobile apps has led to a veritable revolution in the world of enterprise software.

Fueled by venture capital, startups have built out substantial businesses tackling different aspects of what “workplace productivity” can constitute, from tools to improve how to perform in a specific job like sales (Slack being now owned by the giant in that space, Salesforce), through to more specific workplace functionality like organising one’s calendar or meetings, writing and collaborating on documents, creating and managing a project, talking to each other about specific work tasks, and so much more. And big tech companies have not been outside of the game, either. Microsoft and the rest have all stepped up with their own takes on the same problems.

But all this has also created a new kind of productivity problem in the process. Enterprises are often now dealing with a much wider range of apps in their typical workflow. This predicament is not small: it has cost, efficiency, management, security, and attention implications in varying degrees.

The solution here is pretty obvious: move back to all-in-one solutions that take out some of the noise and make it easier to share and hand off work throughout the lifecycle of productivity. It’s something that Microsoft, of course, is already addressing, as are others. But in the wider scheme of things, sometimes building a new set of tools from scratch can yield a much fresher, and better result.

“ClickUp’s sole purpose has always been to make the world more productive. Time is our most valuable resource and we are committed to giving people more time to focus on what matters most to them,” says Zeb Evans, CEO and Founder of ClickUp, in a statement. “We believe software should make people more productive and efficient. I’m thrilled about our next chapter and accelerating the innovations that deliver on this promise to our customers.”

Investors love almost nothing more than a fast-growing startup — and this one definitely fits the bill.

“ClickUp’s unique offering in the market has fueled their rise as one of the fastest-growing SaaS startups in the world. Their strong growth, product adoption, and customer retention reflect the tremendous value they’re providing to businesses looking to drive greater productivity and efficiency,” said David George, general partner at Andreessen Horowitz, in a statement. “ClickUp is synonymous with the future of work, and we’re thrilled to partner with a company that has shown such a strong commitment to its users and product. We look forward to building a more productive world together.”