Greylock Partners

Heading to Startup Grind Conference next week? Don't miss these sessions with the Greylock Partners team and founders we've backed. Details 👇 📍 Tuesday, April 28 | 3:00-3:30 PM | Breakout Stage What Actually Works in AI Marketing (And What Doesn't) Mike Duboe & Matt Hammel, COO & Co-founder of AirOps 📍 Wednesday, April 29 | 3:05-3:30 PM | Main Stage Scaling AI Products Beyond Initial Product-Market Fit Corinne Marie Riley & Tuhin Srivastava, CEO & Co-founder of Baseten See you there!

"Best of all: They have completely stopped asking for a smartphone." Huge thank you to NYT Wirecutter and Alison Rochford for sharing her kids' Tin Can experience and giving everyone the 411. 📞 https://lnkd.in/g2F36W-N

Congrats to Cylake and Tenzai for being recognized on CTech by Calcalist's 2026 list of most promising Israeli startups. ▪️ Cylake is building a complete, AI-native, data-driven cybersecurity platform for the world’s largest and most regulated institutions. The company is designed to operate on-premises or in private cloud environments, so that customers retain full data and operational control. ▪️ Tenzai is an AI-native cybersecurity company building cutting-edge AI hackers to ensure enterprises deliver unbreakable code. Its platform actively hacks, exploits, and helps fix vulnerabilities across enterprise software - continuously and at scale. We at Greylock Partners are proud to be the first partner to Cylake and Tenzai, and their incredible teams.

Spiros Xanthos has spent more than two decades building systems to help engineers monitor and troubleshoot complex software. Yet the most punishing part of the job never changes: When something breaks, on-call engineers are on the hook to fix it, even if it’s the middle of the night. While overseeing cybersecurity and data platform Splunk’s software monitoring teams, Xanthos saw this strain firsthand as his teams integrated newly acquired tools while trying to keep its existing systems running. “[It] was so hard on our site reliability engineers,” Xanthos says. “Over a period of six months, we lost 90% of them. It was a complete burnout.” That experience led Xanthos and his cofounder Mayank Agarwal to launch Resolve AI in 2024 to automate the painful process of responding to production issues. Traditionally, teams rotate who has to be on call, where developers are paged when systems fail. With Resolve’s system, multiple agents investigate when a problem is flagged. They orchestrate a host of AI models and tools to analyze logs, metrics and test different hypotheses like traffic spikes or faulty code. If Resolve can automatically fix the issue, it will. If it’s more complex, the system will present a recommended solution to a human engineer, who can review and approve it. Keep reading to learn more: https://lnkd.in/esFuMH3s (Photo: Resolve AI)

We recently announced the formation of Cylake’s Board of Directors, bringing together leaders who have helped build and scale some of the most consequential cybersecurity companies. We asked Asheem Chandna why he chose to join the board and what he sees changing in cybersecurity. “I have spent more than two decades working with companies building cybersecurity systems at scale. What has become clear is that not every organization can adopt the same architectural model. There is a growing segment of institutions operating under strict regulatory and operational constraints where existing systems were never designed to hold. What makes this shift different is that AI can now operate on this data at scale. Most systems were never designed for that. Cylake is approaching this from first principles, operating on all data under full control in an AI-native way. That is what makes this necessary and inevitable.” Asheem brings decades of experience identifying and building category-defining companies, including Palo Alto Networks. 

The floor was raised last year. AI gave low-skill attackers the ability to execute at a level of sophistication that would have been out of reach twelve months earlier. Now the ceiling is being raised. Capabilities that used to require nation-state budgets and dedicated research teams are about to proliferate. What a frontier lab can do today, open-source models tend to match within 12 to 18 months (or less). Defenders are already underwater. Backlogs of hundreds of thousands of known vulnerabilities. Remediation windows collapsing from weeks to hours. And the volume of what's coming next will be an order of magnitude worse. Human-speed remediation workflows cannot absorb machine-speed vulnerability discovery. The only way to match the tempo of AI-driven offense is with AI-driven defense. I wrote about what Mythos actually means for security teams, and why the organizations that are most successful won't be the ones that hired more analysts or ran more scans. Link in comments.

Today, Resolve AI is announcing the launch of Resolve AI Labs and a $40M Series A extension at a $1.5B valuation, with DST Global and Salesforce Ventures joining us. A thesis we've been developing at Greylock Partners: the winning AI-native companies will be full-stack and need to own the model, the harness, and the product surface. The hardest verticals demand optimization at every layer of the stack to drive the domain-specific accuracy, reliability, and long-horizon reasoning these workloads require. Production engineering is exactly that kind of domain, where agents have to reason over practically infinite data, orchestrate dozens of tools, and execute long-horizon tasks with real consequences for mistakes. Resolve AI Labs is Resolve's move into owning the full-stack. To lead it, Spiros Xanthos and Mayank Agarwal recruited Dhruv Mahajan as Chief AI Scientist, who most recently led post-training for large-scale Llama foundation models at Meta Superintelligence Labs. Sean Bell, who led all pre-training data efforts for Meta foundation models, is joining alongside him. And we have a few more incredibly talented researchers joining soon. The customer momentum continues to accelerate at Resolve on the back of their full-stack approach. Meir Amiel, President and Chief Trust and Infrastructure Officer at Salesforce, said it well: Resolve has changed how their teams work through production incidents, and their engineers are now focused on the work that actually drives impact. Onwards! cc Greylock Partners, Corinne Marie Riley, Holly Rose Faith, Glen Evans, Lee Haney

Today we're announcing the launch of Resolve AI Labs and an additional $40 million in our Series A Extension at a $1.5 billion valuation led by DST Global and Salesforce Ventures. Agents that debug and run production is way more than a harness on top of a frontier model pointed at infrastructure. Requires dealing with practically infinite data, tens to tools, very complex reasoning trees, and very long horizon tasks. Simple agents on top of frontier models fall short on accuracy, reliability and performance. Resolve AI Labs is our investment in building SOTA agents and models for production engineering, a very deep and wide domain that we feel can be better served with domain optimized models. To do that we convinced Dhruv Mahajan to come and lead the lab. Dhruv has deep expertise in AI and LLMs and most recently led post-training for large-scale Llama foundation models at Meta. Alongside Dhruv, Sean Bell led all pre-training data efforts for Meta foundation models has joined us as well. We are also excited to announce additional researchers soon. We are already seeing huge impact at customers like Salesforce, DoorDash, Coinbase, and Zscaler. Meir Amiel, President, Chief Trust and Infrastructure Officer at Salesforce, put it well: "Resolve AI has changed how our teams work through production incidents. What used to take hours of manual investigation and coordination across teams now gets resolved in a fraction of the time. Our engineers aren't only faster, they're focused on the work that actually drives impact." The team we've assembled over the past two years is going to build a world where AI removes the burden from engineers and removes the constraints from production for good. I’m very excited to continue this journey with Mayank Agarwal and the Resolve team! Mayank, Dhruv, and I spoke with Forbes about the news. See the full story: https://lnkd.in/gC7QTAM9

Exciting news from the Resolve AI team this morning! Resolve announced additional Series A funding at a $1.5B valuation, bringing their total raised to over $190M in just 18 months since emerging from stealth with a seed round led by us at Greylock Partners. Alongside the funding, they're launching Resolve AI Labs, a dedicated research initiative focused on the domain-specific models, evaluation systems, and agentic architectures needed to make AI truly reliable in production environments. Leading the effort is Chief AI Scientist Dhruv Mahajan, who previously led post-training for Meta's Llama foundation models. And it doesn't stop there. Resolve AI was also named to the Forbes AI Brink List, recognizing the 20 most promising Seed and Series A-stage startups building in AI. Congratulations to Spiros Xanthos, Mayank Agarwal, and the entire Resolve AI team on the incredible momentum. And welcome, Dhruv! cc Saam Motamedi and Corinne Marie Riley

In today's newsletter, we welcome the newest member of the Greylock Partners investment team: Neiman Mathew. Neiman is very passionate about working with the best engineers, researchers and product managers, to brainstorm and help initiate and build the most important companies in the AI era. At Greylock, he'll be focused on partnering with early-stage founders often even before they have a business idea, and particularly around the next generation AI stack. Read more about Neiman 👇