Skip to main content
​
May 25 – May 31, 2026

​
New features

  • Update sandbox network rules at runtime. Call sandbox.updateNetwork() (JS) / sandbox.update_network() (Python) to change a running sandbox’s network configuration without restarting it. See Internet access.
  • Structured network rules with per-host transforms. Define network rules as structured objects and apply per-host transforms (for example, header injection or URL rewrites) when sandboxes call out to the internet. See Internet access.
  • AbortSignal support for template operations. Cancel template builds and other long-running template calls from the JS SDK using a standard AbortSignal. See the JS SDK reference.
  • Client-side API key validation. Both SDKs now validate the format of your E2B_API_KEY before making any request, so misconfigured keys fail fast with a clear error.

​
Updates

  • JS SDK uses HTTP/2 with a stable sandbox host URL. Sandbox traffic now goes through a stable host with HTTP/2 by default, reducing connection overhead and improving latency for high-throughput agents.
  • Configurable HTTP/2 in the Python SDK. You can now opt out of HTTP/2 when constructing the transport if your environment requires HTTP/1.1.
  • Higher concurrency limits in the JS SDK. Default max-concurrency settings have been increased so large agent workloads need less manual tuning.
  • Faster sandbox builds. Template builds now parallelize fragmented backing reads and stream compressed templates directly to storage on upload, cutting build and upload times for large templates.
  • Lower memory pressure on long-running sandboxes. Page-fault handling and storage upload paths have been reworked to reduce copying and free buffers sooner, improving stability for memory-heavy workloads.

​
Bug fixes

  • Fixed fromDockerfile / from_dockerfile to correctly handle multi-source COPY and ADD instructions when building custom templates.
  • Fixed gRPC streams not closing cleanly on watcher and command teardown in the Python SDK, which could leak connections on sandbox shutdown.
  • Fixed lifecycle.on_timeout and auto_pause precedence so they now behave consistently across both SDKs. See Sandbox lifecycle.
  • Fixed the CLI e2b auth login flow on headless machines where xdg-open is unavailable — the CLI now prints the login URL instead of failing. See CLI.
  • Fixed Python envd transport stability issues that could cause intermittent disconnects under load.
  • Improved sandbox cluster reliability: nodes are no longer evicted from the local view during routine sync, reducing transient sandbox unavailability.
  • Removed the deprecated Sandbox.betaCreate / beta_create methods. Use Sandbox.create / Sandbox.create instead.