ST-2026-034 · SDKs, clients & toolchains
Cloudflare phases out Sandbox SDK transports and helper features
Cloudflare removed HTTP and WebSocket transports from Sandbox SDK releases after 9 July 2026 and is moving callers to RPC while retiring several helper features.
Previous state
Sandbox SDK users could rely on HTTP or WebSocket transports, desktop helpers, exposePort and default-session conveniences.
Current state
RPC is the transport replacement; desktop support is removed, Cloudflare Tunnel displaces exposePort, and further legacy conveniences are scheduled for removal.
Affected users
Who needs to care
Developers and platform teams upgrading applications built on Cloudflare Sandbox SDK.
Required response
What to do
Audit SDK transport and session assumptions, migrate to RPC and supported tunnel patterns, and test against a post-cutoff release.
Evidence boundary
What the source does not prove
The source does not name one universal first post-cutoff SDK version for every removal or a removal version for every scheduled helper.
Lifecycle history
Dated event sequence
- Change documented
Cloudflare removed HTTP and WebSocket transports from Sandbox SDK releases after 9 July 2026 and is moving callers to RPC while retiring several helper features.
- Effective milestone
RPC is the transport replacement; desktop support is removed, Cloudflare Tunnel displaces exposePort, and further legacy conveniences are scheduled for removal.
Evidence ledger
First-party sources
- 01Cloudflare Developers — Deprecating Sandbox SDK features
Official product documentation or changelog · 2026-06-09
Open official source ↗