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Author and test an environment with the SDK guide. This page is the platform half, from hud deploy to a running task. A first deployment needs a team API key and two commands:
Create a key under API Keys. After the upload begins, open Environments to follow the build.

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Environment, build, and template

An environment is the stable platform record. Each deployment creates a build, an immutable version of its source and runnable image. A successful build exposes the environment’s @env.template() definitions as task templates. This separation lets you inspect old builds while new work is building. Runs started during an active build can continue using the previous successful build until the new one is ready.

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Follow a deployment

The environment page shows an active build on the overview and keeps the full history under Builds. Open a build to read its logs and source. A failed build does not replace the latest successful one.

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Configure runtime variables

An environment can declare variables that its tasks need, such as credentials for an external service. Open Settings to add them. Values are masked after saving and injected when HUD starts an instance for that environment. The overview separates missing required variables from optional ones. A task cannot run until the variables required by its template are configured.
Compute resources and timeouts belong to the task’s RuntimeConfig, not the environment settings page. This keeps placement requirements attached to the work that needs them.

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Choose hosted compute

HUD supports EC2 and Modal for hosted environment runs. Select EC2 with hud deploy --runtime hud or Modal with hud deploy --runtime modal. A Compose deployment uses Modal automatically. The selection is saved on the environment and applies to future builds and rollouts unless a task provides its own runtime override. With Modal, HUD builds a provider-native image and starts each rollout in a fresh, isolated Modal sandbox. HUD still schedules the work and records its logs, traces, and result; Modal supplies the compute instead of HUD’s managed AWS runtime. This hosted option does not require your own Modal account. This setting is different from the SDK’s ModalRuntime, which runs an evaluation directly through your own Modal account.

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EC2 profiles

EC2 environments run on one of five fixed profiles. An environment without an explicit tier uses the Default profile. Large and Extra Large profiles require the corresponding team access. Current hourly rates and your team’s access appear under Project billing. Modal environments do not use EC2 tiers. HUD currently supports these exact effective RuntimeConfig.resources profiles: The complete effective resource request must match one row. Adding, removing, or changing a CPU, memory, GPU type, or GPU count produces a different billing profile. HUD rejects an unmatched profile before provisioning. The claude_cli and codex_cli agents cannot run with a GPU. HUD rejects a run that pairs one of them with a GPU profile when you launch it.

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Run a task template

Open Templates after the build succeeds. Select a template, fill its arguments, choose a model, and start a run. HUD creates a job containing one or more traces and opens the job page as soon as the batch is queued. For a reusable suite, create concrete tasks from the template and group them in a taskset. Tasksets are the normal input to a multi-model evaluation.

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Read the environment page

Public viewers see the overview and templates. Editors see the operational tabs.

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Share or publish

Share grants another team or member scoped access without making the environment public. Make public lists a private environment in the catalog. The button is visible to everyone on a private environment; it is disabled with a reason if you cannot use it (no permission, no successful build, or legacy SDK v5). The owner or a team admin can confirm from the environment header or Settings. An external registry does not need a build. Use Public view to preview what other users will see. Make private on Settings removes the catalog listing without affecting shares. The tasks that belong with the environment publish through tasksets.