Anthropic / Code with Claude London Code with Claude London: Self-Hosted Sandboxes and MCP Tunnels Arrive for Enterprise Agents
Anthropic's London developer conference on May 19 launched self-hosted sandboxes in public beta and MCP Tunnels in research preview, letting enterprise teams run Claude agents inside their own infrastructure for the first time.
Anthropic held Code with Claude London on May 19 at Park Plaza Westminster Bridge, the second stop of its 2026 developer conference tour after the San Francisco event on May 6. The event sold out fast enough that Anthropic added an Extended London day on May 20 specifically for independent developers and early-stage founders. Tokyo follows on June 10.
The SF event covered compute, Managed Agents features, and Claude Code’s three-surface architecture. London added something different: two structural product launches aimed at enterprise teams that need agents running inside their own infrastructure.
Self-Hosted Sandboxes (Public Beta)
The main product announcement was self-hosted sandboxes entering public beta. The architecture splits the agent runtime in two: orchestration stays on Anthropic’s infrastructure, but tool execution moves inside the customer’s own cloud environment. Code and files never leave the customer’s perimeter.
Four launch partners are available on day one: Cloudflare, Daytona, Modal, and Vercel. BYO sandbox is a fifth option for teams with existing container infrastructure. Four organizations shared their production deployments at the event: Amplitude (on Cloudflare), Clay (on Daytona), DoorDash (on Modal), and Rogo (on Vercel).
The tradeoff this addresses is straightforward. Enterprise teams in finance, healthcare, and other regulated sectors have been reluctant to use cloud-hosted coding agents because code execution happens outside their perimeter. Self-hosted sandboxes let them keep Anthropic’s orchestration while keeping execution local. AWS support, session memory for self-hosted deployments, and MCP Tunnels GA status are noted as unavailable at launch.
The timing was deliberate. Anthropic opened London the same week as Google I/O, where Google announced its own Managed Agents API. The two products take opposite approaches: Google runs everything inside Google’s cloud; Anthropic now offers bring-your-own execution environment. Anthropic leaned into the contrast explicitly on stage.
MCP Tunnels (Research Preview)
The second announcement was MCP Tunnels, which entered research preview. The problem it solves: Claude Managed Agents couldn’t previously reach private MCP servers sitting behind a company firewall. With MCP Tunnels, you run a lightweight proxy inside your private network that opens a single outbound encrypted connection to Anthropic. Agents can then call your internal data warehouse, feature flag service, ticketing system, or any other internal tool as if it were a standard public MCP server. No inbound firewall modifications required.
Access is gated for now and managed through the Claude Console.
The State of the Room
Boris Cherny, head of Claude Code, addressed the human side of all this pretty directly. He compared developers who still want to write code by hand to people who shop at farmers’ markets. “I buy my veggies at a farmer’s market. There’s always room for that.” It landed as a genuine acknowledgment rather than a dismissal: some engineers at Anthropic still write code manually on weekends because they miss the craft.
Fiona Fung, head of engineering at Anthropic, framed the practical message more bluntly: “Pick your noisiest workflow, and ask if it’s still serving its purpose. If it’s something that is really expensive, is it something that Claude can handle?”
The enterprise reception was mixed. Startups reported daily Claude Code use but surfaced job security concerns. Attendees from regulated sectors cited oversight requirements that slow adoption. Spotify’s presentation was the headline data point: more than 99% of its engineers use AI coding tools every week, 94% report higher productivity, PR frequency increased 76%, and the company has merged 2.5 million automated maintenance PRs through its internal fleet management system.
Anthropic also disclosed that the majority of code written at Anthropic itself now comes from Claude Code.
What’s Next
The Claude Managed Agents documentation and sandbox cookbooks are at platform.claude.com/docs. The Tokyo edition runs June 10, 2026.
Sources: Self-Hosted Sandboxes and MCP Tunnels announcement — Anthropic; Anthropic lands in London as AI-powered coding goes mainstream — Fortune, May 21, 2026; Code with Claude London event page — Anthropic; Code with Claude London recap — Digital Applied