> ## Documentation Index
> Fetch the complete documentation index at: https://e2b.manicule.dev/llms.txt
> Use this file to discover all available pages before exploring further.
> For every page in one file, fetch https://e2b.manicule.dev/llms-full.txt (large).
> To search and read these docs as tools, connect the MCP server at https://e2b.manicule.dev/api/mcp.
> Every agent surface: https://e2b.manicule.dev/.well-known/llms-manifest.json

# V1 build system deprecation (/docs/migration/v1-build-deprecation)

<!-- agent-signals: reading_time_min: 1 · est_tokens: 282 · updated: 2026-07-30 -->
Related: [SDK v2 migration guide](/docs/migration/v2.md), [V2 build system migration](/docs/migration/template-v2.md), [E2B_ACCESS_TOKEN deprecation](/docs/migration/access-token-deprecation.md), [How do I increase my concurrency limit?](/docs/faq/increase-concurrency.md)

> The V1 template build system is deprecated. Migrate to the V2 build system.

The V1 build system is deprecated, and V2 is now the supported build system. V1 builds stop working on **August 1, 2026**, when [access tokens stop working](/docs/migration/access-token-deprecation) (V1 builds authenticate with `E2B_ACCESS_TOKEN`). Migrate to V2 before then to keep building.

## What changed

The `e2b template build` command that drove V1 builds is now a deprecation stub and exits immediately. The current build command is `e2b template create`, which authenticates with your `E2B_API_KEY` instead of the access token. Migrating to V2 is therefore also what keeps your builds working past the access token cutoff.

## How to migrate

Follow the [V2 migration guide](/docs/migration/template-v2) to move an existing template to the V2 build system. It covers three paths:

* `e2b template migrate` to convert an existing `e2b.toml` and `e2b.Dockerfile` definition (recommended).
* `fromDockerfile()` to keep using a Dockerfile, parsed into a V2 template.
* `fromImage()` to reference a Docker image you build and push yourself.