Sierra, the AI agent company led by Bret Taylor, acquired Takeoff, a San Francisco startup that builds a runtime for AI agents that carry out multi-step jobs over days or weeks. The deal was announced on July 23, 2026, in a post on Sierra's blog written by Takeoff co-founder Aakash Thumaty.
Financial terms were not disclosed. Neither company gave a price, a deal structure or a closing date.
The Takeoff team is joining Sierra, and the two groups are building a new platform called Horizon. Thumaty wrote that Takeoff would keep serving its existing customers and planned to take its long-horizon agents into more markets.
What Takeoff built
Takeoff described its product as a long-horizon agent runtime: software that lets agents handle a complete job rather than a single conversation. A customer sends an API request describing the job, and Takeoff's agents carry it out across voice calls, SMS, email, web portals and APIs over a period of hours to weeks, reporting progress and outcomes back through webhooks. Coverage of the deal said the runtime keeps memory at the level of an individual case.
The company said it spent 14 months building the runtime. In a June post it reported that its agents had handled 3.5 million interactions over the previous six months for customers in five industries, ranging from lending to healthcare. Thumaty wrote that in those industries Takeoff's agents had beaten competing agents in head-to-head comparisons. The companies did not name customers, and the performance claims were not independently verified.
Takeoff did not sell seats or agent frameworks. It priced its work on the outcomes the agents produced rather than on the volume of model inference used.
“Our teams together are building a new platform called Horizon.”
Growth with three people
Takeoff was founded in 2025 and had a team of three when the deal was discussed. Its June funding post was signed by Aakash, Shreya and Spencer. Thumaty previously worked at Salesforce, where, according to one report, he first came to Taylor's attention.
According to Thumaty, Takeoff had $0 in annual recurring revenue at the start of 2026 and nearly eight figures of revenue by early July. He said that growth came from several seven-figure contracts signed within months of the company's last funding round.
On June 10, 2026, Takeoff announced it had raised $15 million from Matrix and Lachy Groom to expand its long-horizon agents. Six weeks later it agreed to join Sierra. Thumaty wrote that the usual next step would have been to hire a sales team and raise more money, and that Sierra instead offered a way to build the same product at greater scale. He argued that in enterprise AI, a strong product without a large deployment operation tends to lose to a weaker product backed by a better one.
Why Sierra is buying
Sierra built its business on AI agents that resolve inbound customer service requests by chat and voice. Its customers include Santander, Rocket Mortgage and Cigna, and the company says almost half of the Fortune 50 use it. Sierra reports more than $150 million in annual recurring revenue and said it was raising $950 million from new and existing investors at a valuation above $15 billion.
About a week before the Takeoff deal, Sierra announced Horizon, a product for agents that pursue a goal, such as originating a loan or obtaining prior authorization for a medical procedure, across inbound and outbound contact that can run for days, weeks or months. A US healthcare provider is a design partner, using Horizon to schedule referrals from primary care physicians to specialists, work that involves dozens of calls and texts between patients, providers and payers.
Takeoff's runtime fits that plan, and the purchase moves Sierra from service resolution toward outbound, revenue-related work. Taylor called Takeoff "the leader in long-horizon AI agents" in a post on X. Sierra said Horizon customers pay for results rather than tokens, the same outcome-based model Takeoff had used.
A shift toward outcome pricing
Thumaty has argued that access to model inference on its own is becoming a commodity, and that the companies that win enterprise contracts will be those that build complete, industry-specific systems and get paid for results.
Other enterprise software vendors have moved in the same direction. Oracle sells outcome-driven agentic applications in its Fusion suite, and Adobe has made an agentic customer experience product available on standalone outcome pricing with no per-seat component.
Sierra did not say how many Takeoff customers would move to Horizon or when the combined platform would be generally available.
