Announcing Claude Compliance API support with Cloudflare CASB

Today, we are extending Cloudflare’s cloud access security broker (CASB) to support the Claude Compliance API. Security and compliance teams can now monitor Claude usage directly in the Cloudflare dashboard. No endpoint agents required.

Enterprise security teams have long struggled to see how users interact with sanctioned and unsanctioned applications. The rapid adoption of AI applications has made this harder. Employees spend significant time in these new surface areas, and their interactions differ from traditional SaaS: users upload files, share freeform prompts, and providers generate content that may contain sensitive data.

Cloudflare CASB helps solve this problem. One API integration gives you out-of-band visibility and control over the applications your organization uses. This integration builds on our existing support for AI governance, extending coverage over the most common tools security teams now manage. 

AI adoption has outpaced security governance. While IT and security teams raced to enable AI tools for productivity, the controls lagged behind. Most organizations today operate with partial visibility: they may block unauthorized AI tools at the network layer, but they cannot see what happens inside sanctioned ones.

This matters because AI tools are not like traditional SaaS Continue reading

Announcing Claude Managed Agents on Cloudflare

Cloudflare and Anthropic have collaborated to integrate Claude Managed Agents with Cloudflare Sandboxes. Our new integration gives you more control over your agent sandboxes, secures connections to private services, and improves observability.

In the past year, Cloudflare’s Developer Platform has expanded to give more developers the tools they need to run agents at scale. This includes:

• Sandboxes for full stateful Linux microVMs at scale

• Agents SDK, providing simple and customizable agent framework

• Browser Run, which gives agents fully programmable and observable browsers

• Dynamic Workers, allowing for dynamic sandboxed code execution at massive scale

Our goal is to make Cloudflare the simplest, most secure, and most programmable cloud for agents.

Integrating with Claude Managed Agents is another step in this direction. You can run your agent loop on the Claude Platform, while using Cloudflare to execute code, secure connections, and run custom tool calls.

To get going in just minutes, we’ve created a default deployment template that gives you the following:

• Enhanced security - Run all agent traffic through customizable proxies. This allows you to securely inject credentials, prevent data exfiltration, and better observe how your agents interact with the outside world.

• Sandbox control and observability - Get Continue reading

Project Glasswing: what Mythos showed us

For the last few months, we've been testing a range of security-focused LLMs on our own infrastructure. These LLMs help identify potential vulnerabilities in our own systems, so we can fix them – and they also show us what attackers are going to be able to do with the latest models.

None of these LLMs has captured more attention than Mythos Preview, from Anthropic. A few weeks ago, we were invited to use Mythos Preview as part of Project Glasswing. We soon pointed it at more than fifty of our own repositories – to see what it would find, and to see how it works.

This post shares what we observed, what the models did well and what they didn't, and how the architecture and process around them needs to change, so they can be used at scale.

Mythos Preview is a real step forward, and it's worth saying that plainly before getting into anything else. We've been running models against our code for a while now, and the jump from what was possible with previous general-purpose frontier models to what Mythos Preview does today is not just a refinement of what came before.

It's Continue reading

Our billing pipeline was suddenly slow. The culprit was a hidden bottleneck in ClickHouse

At Cloudflare, we are heavy users of ClickHouse, an open-source analytical database management system. We redesigned one of our largest ClickHouse tables to add a column to the partitioning key. The change enabled per-tenant retention on a table that serves hundreds of internal teams. The design went through several rounds of revision and review with engineers across multiple teams before we landed on the final approach. But a few weeks after rollout, the jobs that produce most of Cloudflare's bills were running up against their hard daily deadline.

All the usual suspects looked clean: I/O, memory, rows scanned, parts read. Everything we would normally check when a ClickHouse query is slow appeared to be normal. The problem turned out to be lock contention in query planning, something we'd never had reason to look for before.

This is the story of how this migration exposed a hidden bottleneck in ClickHouse's internals, and the patches we wrote to fix it.

We use ClickHouse to store over a hundred petabytes of data across a few dozen clusters. To simplify onboarding for our many internal teams, we built a system called "Ready-Analytics" in early 2022.

The premise is Continue reading

Browser Run: now running on Cloudflare Containers, it’s faster and more scalable

We’ve enabled higher usage limits, faster performance, and better reliability for Browser Run by rebuilding on top of Cloudflare’s Containers.

You can now spin up 60 browsers per minute via the Workers binding and run up to 120 concurrently — 4x the previous limit. Also, Quick Action response times dropped more than 50%. You don't need to change anything: these improvements are live today. On top of that, we’re shipping fixes and new features faster than before. Read on to learn how we did it and see the data.

Browser Run enables developers to programmatically control and interact with headless browser instances running on Cloudflare’s global network. That’s useful for end-to-end testing of web applications, securely investigating suspicious URLs, and leveraging how browsers can easily render PDF documents, amongst other quick actions like capturing screenshots and extracting content. More recently, it’s become a critical enabler of AI agents to interact with the web. We’re building Browser Run to be the go-to platform to responsibly utilize automated browsers securely at massive scale.

Before adopting Cloudflare Containers, we shared infrastructure with Browser Isolation (BISO). While technically similar, BISO’s larger container images slowed Continue reading

When “idle” isn’t idle: how a Linux kernel optimization became a QUIC bug

CUBIC, standardized in RFC 9438, is the default congestion controller in Linux, and as a result governs how most TCP and QUIC connections on the public Internet probe for available bandwidth, back off when they detect loss, and recover afterward. At Cloudflare, our open-source implementation of QUIC, quiche, uses CUBIC as its default congestion controller, meaning this code is in the critical path for a significant share of the traffic we serve.

In this post, we’ll tell the story of a bug in which CUBIC's congestion window (cwnd) gets permanently pinned at its minimum and never recovers from a congestion collapse event.

The story starts with a Linux kernel change aimed at bringing CUBIC into line with the app-limited exclusion described in RFC 9438 §4.2-12 — a fix to a real problem in TCP that, when ported to our QUIC implementation, surfaced unexpected behaviors in quiche. It has a happy ending: an elegant (near-)one-line fix that broke the cycle.

Before we dive into the core problem, a quick refresher on Congestion Control Algorithms (CCAs) may help to set the stage.

The central knob a CCA turns is the congestion window (cwnd Continue reading

Building for the future

This afternoon, we sent the following email to our global team. One of our core values at Cloudflare is transparency, and we believe it's important that you hear this directly from us because it’s a major moment at Cloudflare. 

Team:

We are writing to let you know directly that we’ve made the decision to reduce Cloudflare’s workforce by more than 1,100 employees globally. 

The way we work at Cloudflare has fundamentally changed. We don’t just build and sell AI tools and platforms. We are our own most demanding customer. Cloudflare’s usage of AI has increased by more than 600% in the last three months alone. Employees across the company from engineering to HR to finance to marketing run thousands of AI agent sessions each day to get their work done. That means we have to be intentional in how we architect our company for the agentic AI era in order to supercharge the value we deliver to our customers and to honor our mission to help build a better Internet for everyone, everywhere. 

Today is a hard day. This decision unfortunately means saying goodbye to teammates who have contributed meaningfully to our mission and to building Cloudflare Continue reading

How Cloudflare responded to the “Copy Fail” Linux vulnerability

On April 29, 2026, a Linux kernel local privilege escalation vulnerability was publicly disclosed under the name "Copy Fail" (CVE-2026-31431). Cloudflare’s Security and Engineering teams began assessing the vulnerability as soon as it was disclosed. We reviewed the exploit technique, evaluated exposure across our infrastructure, and validated that our existing behavioral detections could identify the exploit pattern within minutes. 

There was no impact to the Cloudflare environment, no customer data was at risk, and no services were disrupted at any point. Read on to learn how our preparedness paid off. 

Cloudflare operates a global Linux server infrastructure at an immense scale, with datacenters located across 330 cities. We maintain a custom Linux kernel build based on the community's Long-Term Support (LTS) versions to manage updates effectively at this volume. At any given time, we may utilize multiple LTS versions from various series, such as 6.12 or 6.18, which benefit from extended update periods.

The community regularly merges and releases security and stability updates which trigger an automated job to generate a new internal kernel build approximately every week. These builds undergo testing in our staging data centers to Continue reading

When DNSSEC goes wrong: how we responded to the .de TLD outage

On May 5, 2026, at roughly 19:30 UTC, DENIC, the registry operator for the .de country-code top-level domain (TLD), started publishing incorrect DNSSEC signatures for the .de zone. Any validating DNS resolver receiving these signatures was required by the DNSSEC specification to reject them and return SERVFAIL to clients, including 1.1.1.1, the public DNS resolver operated by Cloudflare.

The country-code top-level domain for Germany, .de, is one of the largest on the Internet. On Cloudflare Radar, it consistently ranks among the most broadly queried TLDs globally. An outage at this level of the DNS hierarchy has the potential to make millions of domains unreachable.

In this post, we’ll walk through what we saw, the impact of these events, and how we applied temporary mitigations while DENIC resolved the issue.

DNSSEC (Domain Name System Security Extensions) adds cryptographic authentication to DNS. When a zone is signed with DNSSEC, each set of records is accompanied by a digital signature known as an RRSIG record that lets a resolver verify the records haven’t been tampered with. Unlike encrypted DNS protocols, such as DNS over TLS (DoT) and DNS over HTTPs (DoH), DNSSEC is about Continue reading

Code Orange: Fail Small is complete. The result is a stronger Cloudflare network

Over the past two and a bit quarters, we've undertaken an intensive engineering effort, internally code-named "Code Orange: Fail Small", focused on making Cloudflare's infrastructure more resilient, secure, and reliable for every customer.

Earlier this month, the Cloudflare team finished this work.

While improving resiliency will never be a “job done” and will always be a top priority across our development lifecycle, we have now completed the work that would have avoided the November 18, 2025 and December 5, 2025 global outages.

This work focused on several key areas: safer configuration changes, reducing the impact of failure, and revising our “break glass” procedures and incident management. We also introduced measures to prevent drift and regressions over time, and strengthened the way we communicate to our customers during an outage.

Here we explain in depth what we shipped, and what it means for you.

What it means for you: In most cases, Cloudflare internal configuration changes no longer reach our network instantly and are instead rolled out progressively with real-time health monitoring. This allows our observability tools to catch problems and revert issues before they affect your traffic.

In order to catch potentially dangerous deployments Continue reading

Introducing Dynamic Workflows: durable execution that follows the tenant

When we first launched Workers eight years ago, it was a direct-to-developers platform. Over the years, we have expanded and scaled the ecosystem so that platforms could not only build on Workers directly, but they could also enable their customers to ship code to us through many multi-tenant applications. We now see on Workers: Applications where users describe what they want, and the AI writes the implementation. Multi-tenant SaaS where every customer's business logic is, at runtime, some TypeScript the platform has never seen before. Agents that write and run their own tools. CI/CD products where every repo defines its own pipeline.

Last month, when we shipped the Dynamic Workers open beta, we gave those platforms a clean primitive for the compute side: hand the Workers runtime some code at runtime, get back an isolated, sandboxed Worker, on the same machine, in single-digit milliseconds. Durable Object Facets extended the same idea to storage — each dynamically-loaded app can have its own SQLite database, spun up on demand, with the platform sitting in front, as a supervisor. Artifacts did the same for source control: a Git-native, versioned filesystem you can create by the tens of millions, one per agent, Continue reading

Post-quantum encryption for Cloudflare IPsec is generally available

While more than two-thirds of human-generated TLS traffic to Cloudflare is already protected by post-quantum cryptography, the world of site-to-site networking has been a different story. For years, the IPsec community remained caught between the high bar of Internet-scale interoperability and the niche requirements of specialized hardware. That gap is now closing. 

Earlier this month, we announced that Cloudflare has moved its target for full post-quantum security forward to 2029, spurred by several recent advances in quantum computing. To advance that goal, we’ve made post-quantum encryption in Cloudflare IPsec generally available.

Using the new IETF draft for hybrid ML-KEM (FIPS 203), we’ve successfully tested interoperability with branch connectors from Fortinet and Cisco — meaning you can start protecting your wide-area network (WAN) against harvest-now-decrypt-later attacks today using hardware you already have.

This post explains how we implemented the new hybrid IPsec handshake, why it took four years longer to land than its TLS counterpart, and how the industry is finally consolidating around a standard that works at Internet scale.

Cloudflare IPsec is a WAN Network-as-a-Service that replaces legacy network architectures by connecting data centers, branch offices, and cloud VPCs to Cloudflare's global IP Anycast Continue reading

Agents can now create Cloudflare accounts, buy domains, and deploy

Coding agents are great at building software. But to deploy to production they need three things from the cloud they want to host their app — an account, a way to pay, and an API token. Until now these have been tasks that humans handle directly. Increasingly, agents handle them on the user’s behalf. The agent needs to perform all the tasks a human customer can. They’re given higher-order problems to solve and choose to use Cloudflare and call Cloudflare APIs.

Starting today, agents can provision Cloudflare on behalf of their users. They can create a Cloudflare account, start a paid subscription, register a domain, and get back an API token to deploy code right away. Humans can be in the loop to grant permission, but no human steps are required from start to finish. There’s no need to go to the dashboard, copy and paste API tokens, or enter credit card details. Without any extra setup, agents have everything they need to deploy a new production application in one shot. And with Cloudflare’s Code Mode MCP server and Agent Skills, they’re even better at it.

This all works via a new protocol that we’ve co-designed with Stripe as part Continue reading

Shutdowns, power outages, and conflict: a review of Q1 2026 Internet disruptions

In the first quarter of 2026, government-directed shutdowns figured prominently, with prolonged Internet blackouts in both Uganda and Iran, a stark contrast to the lack of observed government-directed shutdowns in the same quarter a year prior. This quarter, we also observed a number of Internet disruptions caused by power outages, including three separate collapses of Cuba's national electrical grid. Military action continued to disrupt connectivity in Ukraine and also impacted hyperscaler cloud infrastructure in the Middle East. Severe weather knocked out Internet connectivity in Portugal, while cable damage disrupted connectivity in the Republic of Congo. A technical problem hit Verizon Wireless in the United States, and unknown issues briefly disrupted connectivity for customers of providers in Guinea and the United Kingdom.

This post is intended as a summary overview of observed and confirmed disruptions and is not an exhaustive or complete list of issues that have occurred during the quarter. A larger list of detected traffic anomalies is available in the Cloudflare Radar Outage Center. Note that both bytes-based and request-based traffic graphs are used within this post to illustrate the impact of the observed disruptions, with the choice of metric generally made based on which better illustrates the Continue reading

Making Rust Workers reliable: panic and abort recovery in wasm‑bindgen

Rust Workers run on the Cloudflare Workers platform by compiling Rust to WebAssembly, but as we’ve found, WebAssembly has some sharp edges. When things go wrong with a panic or an unexpected abort, the runtime can be left in an undefined state. For users of Rust Workers, panics were historically fatal, poisoning the instance and possibly even bricking the Worker for a period of time.

While we were able to detect and mitigate these issues, there remained a small chance that a Rust Worker would unexpectedly fail and cause other requests to fail along with it. An unhandled Rust abort in a Worker affecting one request might escalate into a broader failure affecting sibling requests or even continue to affect new incoming requests. The root cause of this was in wasm-bindgen, the core project that generates the Rust-to-JavaScript bindings Rust Workers depend on, and its lack of built-in recovery semantics.

In this post, we’ll share how the latest version of Rust Workers handles comprehensive Wasm error recovery that solves this abort-induced sandbox poisoning. This work has been contributed back into wasm-bindgen as part of our collaboration within the wasm-bindgen organization formed last year. First with panic=unwind support, which ensures that Continue reading

Moving past bots vs. humans

For us humans to interact with the online world, we need a gateway: keyboard, screen, browser, device. What is called "human detection" online are patterns that humans use when interacting with such devices. These patterns have changed in recent years: a startup CEO now uses their browser to summarize the news, a tech enthusiast automates the process to book their concert tickets when sales open at night, someone who's visually impaired enables accessibility on their screen reader, and companies route their employee traffic through zero trust proxies.

At the same time, website owners are still looking to protect their data, manage their resources, control content distribution, and prevent abuse. These problems aren’t solved by knowing whether the client is a human or a bot: There are wanted bots and there are unwanted humans. These problems require knowing intent and behavior. The ability to detect automation remains critical. However, as the distinctions between actors become blurry, the systems we build now should accommodate a future where "bots vs. humans" is not the important data point.

What actually matters is not humanity in the abstract, but questions such as: is this attack traffic, is that crawler load proportional to the traffic it Continue reading

Orchestrating AI Code Review at scale

Code review is a fantastic mechanism for catching bugs and sharing knowledge, but it is also one of the most reliable ways to bottleneck an engineering team. A merge request sits in a queue, a reviewer eventually context-switches to read the diff, they leave a handful of nitpicks about variable naming, the author responds, and the cycle repeats. Across our internal projects, the median wait time for a first review was often measured in hours.

When we first started experimenting with AI code review, we took the path that most other people probably take: we tried out a few different AI code review tools and found that a lot of these tools worked pretty well, and a lot of them even offered a good amount of customisation and configurability! Unfortunately, though, the one recurring theme that kept coming up was that they just didn’t offer enough flexibility and customisation for an organisation the size of Cloudflare.

So, we jumped to the next most obvious path, which was to grab a git diff, shove it into a half-baked prompt, and ask a large language model to find bugs. The results were exactly as noisy as you might expect, with a flood Continue reading

The AI engineering stack we built internally — on the platform we ship

In the last 30 days, 93% of Cloudflare’s R&D organization used AI coding tools powered by infrastructure we built on our own platform.

Eleven months ago, we undertook a major project: to truly integrate AI into our engineering stack. We needed to build the internal MCP servers, access layer, and AI tooling necessary for agents to be useful at Cloudflare. We pulled together engineers from across the company to form a tiger team called iMARS (Internal MCP Agent/Server Rollout Squad). The sustained work landed with the Dev Productivity team, who also own much of our internal tooling including CI/CD, build systems, and automation.

Here are some numbers that capture our own agentic AI use over the last 30 days:

• 3,683 internal users actively using AI coding tools (60% company-wide, 93% across R&D), out of approximately 6,100 total employees

• 47.95 million AI requests 

• 295 teams are currently utilizing agentic AI tools and coding assistants.

• 20.18 million AI Gateway requests per month

• 241.37 billion tokens routed through AI Gateway

• 51.83 billion tokens processed on Workers AI

The impact on developer velocity internally is clear: we’ve never seen a quarter-to-quarter increase in merge requests to this degree.

As AI Continue reading

Building the agentic cloud: everything we launched during Agents Week 2026

Today marks the end of our first Agents Week, an innovation week dedicated entirely to the age of agents. It couldn’t have been more timely: over the past year, agents have swiftly changed how people work. Coding agents are helping developers ship faster than ever. Support agents resolve tickets end-to-end. Research agents validate hypotheses across hundreds of sources in minutes. And people aren't just running one agent: they're running several in parallel and around the clock.

As Cloudflare's CTO Dane Knecht and VP of Product Rita Kozlov noted in our welcome to Agents Week post, the potential scale of agents is staggering: If even a fraction of the world's knowledge workers each run a few agents in parallel, you need compute capacity for tens of millions of simultaneous sessions. The one-app-serves-many-users model the cloud was built on doesn't work for that. But that's exactly what developers and businesses want to do: build agents, deploy them to users, and run them at scale.

Getting there means solving problems across the entire stack. Agents need compute that scales from full operating systems to lightweight isolates. They need security and identity built into how they run.  They need an agent toolbox Continue reading

Introducing the Agent Readiness score. Is your site agent-ready?

The web has always had to adapt to new standards. It learned to speak to web browsers, and then it learned to speak to search engines. Now, it needs to speak to AI agents.

Today, we are excited to introduce isitagentready.com — a new tool to help site owners understand how they can make their sites optimized for agents, from guiding agents on how to authenticate, to controlling what content agents can see, the format they receive it in, and how they pay for it. We are also introducing a new dataset to Cloudflare Radar that tracks the overall adoption of each agent standard across the Internet.

We want to lead by example. That is why we are also sharing how we recently overhauled Cloudflare's Developer Documentation to make it the most agent-friendly documentation site, allowing AI tools to answer questions faster and significantly cheaper.

The short answer: not very. This is expected, but also shows how much more effective agents can be than they are today, if standards are adopted.

To analyze this, Cloudflare Radar took the 200,000 most visited domains on the Internet; filtered out categories where agent readiness isn't important Continue reading