# e2b@2.56.0

Category: agent-infrastructure
Published: 2026-10-13T15:02:37Z
Source: [E2B releases](https://github.com/e2b-dev/E2B/releases/tag/e2b%402.56.0)
Agent usefulness: 94/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-13T18:17:37.298Z
Tags: sandbox, code-execution, agents

## Human Summary
E2B 2.56.0 drops support for Node.js 20, requiring Node.js 22.19.0+, adopts undici 8, and replaces SDK in-flight request caps with connection pool configurations.

## Agent Summary
E2B version 2.56.0 introduces breaking runtime requirements: Node.js 22.19.0+ is now required (dropping Node 20) and undici is upgraded to ^8. SDK-level in-flight request caps and related environment variables (E2B API INFLIGHT REQUESTS, E2B ENVD INFLIGHT REQUESTS, E2B ENVD RPC INFLIGHT REQUESTS) have been removed in favor of undici connection pooling variables (E2B API CONNECTIONS, E2B ENVD RPC CONNECTIONS).

## Body
E2B release 2.56.0 includes major environment and transport updates. Node.js 20 is no longer supported, establishing a minimum requirement of Node.js 22.19.0. The SDK now depends exclusively on undici@^8, which handles HTTP/2 SETTINGS MAX CONCURRENT STREAMS and provisions additional connections upon saturation. Consequently, the SDK-level in-flight request cap has been removed along with configuration variables E2B API INFLIGHT REQUESTS , E2B ENVD INFLIGHT REQUESTS , and E2B ENVD RPC INFLIGHT REQUESTS . Concurrency is now controlled through undici connection pool settings via E2B API CONNECTIONS and E2B ENVD RPC CONNECTIONS . Dependencies were also updated, including @e2b/dockerfile-utils@0.1.1 .

## Recommended actions
- Upgrade runtime environment to Node.js 22.19.0 or newer.
- Remove deprecated environment variables: E2B API INFLIGHT REQUESTS, E2B ENVD INFLIGHT REQUESTS, and E2B ENVD RPC INFLIGHT REQUESTS.
- Configure concurrency using E2B API CONNECTIONS and E2B ENVD RPC CONNECTIONS if connection limits are required.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
Sponsor inventory is available at /api/sponsors.json with useCases, pricing, API/docs URLs, targetAgents, constraints, CTA URL, commercial disclosure fields, sourceOfTruthUrl, constraintsLastVerifiedAt, constraintsRefreshCadence, driftHandlingPolicy, and constraintPolicy.