Update an environment

Changes any mix of the environment’s settings in one atomic write and creates its next revision. The body is a merge patch: an omitted setting keeps its current value. This is how you deploy, scale, and change variables.

What happens to running instances depends on what changed. A change to the image, weights, CPU or memory, extra_args, or variables replaces the instances by deployment_strategy. A change to instances alone adds or removes instances and replaces none. A change to the accelerator list replaces only the instances that move to another configuration. A write that changes nothing creates no revision and returns the environment as it was.

The result must be complete: it needs an image, instances, and resources.accelerators ([] is CPU). Otherwise the write returns 409 failed_precondition with reason environment_incomplete and lists missing_fields.

Writes to one environment apply in order, and the last write wins. Send If-Match with the ETag you read to refuse a stale write with 412 etag_mismatch. After a 500 or a lost response, read the environment before you retry: the write may have landed.

Requires the account_admin or developer role and Serve access. All environments of an account share its per-region accelerator quota.

PATCH

projects

{proj_id}

environments

{env}

curl --request PATCH \
  --url https://api.reactor.inc/projects/{proj_id}/environments/{env} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "image": {
    "tag": "v1.3.0"
  }
}
'

{
  "id": "4b5c6d7e-8f90-4a1b-8c2d-3e4f5a6b7c8d",
  "project_id": "0d3c6f4e-8a1b-4c2d-9e7f-1a2b3c4d5e6f",
  "name": "production",
  "image": {
    "tag": "v1.3.0",
    "digest": "sha256:d138642b1cd5ea5bba6ed5655fa1d7dfced33889d149b094b2c32c32f09ed3da",
    "ref": null
  },
  "weights": null,
  "resources": {
    "accelerators": [
      {
        "type": "NVIDIA_H100",
        "count": 1
      }
    ]
  },
  "extra_args": [],
  "node_selector": null,
  "instances": [
    {
      "count": 3,
      "regions": {
        "prefer": [
          "us-east"
        ]
      }
    }
  ],
  "variables": {
    "LOG_LEVEL": {
      "value": "debug"
    },
    "API_KEY": {
      "secret": "prod-api-key",
      "version_id": "018cc820-e222-7ba6-9f43-7cf0b7e3a112"
    }
  },
  "revision": {
    "number": 4,
    "created_by": {
      "user_id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d"
    },
    "created_at": "2026-10-10T11:16:40Z"
  },
  "public": false,
  "created_at": "2026-10-09T08:53:20Z",
  "deleted_at": null
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "failed_precondition",
  "reason": "environment_incomplete",
  "message": "environment staging is not complete: set image",
  "missing_fields": [
    "image"
  ]
}

{
  "error": "etag_mismatch",
  "message": "environment staging is at revision 4, not 3"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>",
  "quota_type": "<string>",
  "limit": "<string>",
  "current": "<string>",
  "field": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

Authorizations

Authorization

string

header

required

A Reactor API key (rk_...), sent as Authorization: Bearer rk_.... Keep it on a server.

Headers

If-Match

string

The ETag of your last read, a revision number in quotes. If the environment's newest revision differs, the write is 412 etag_mismatch and nothing is written. A weak tag, a list, or * is 400.

Example:

"\"3\""

Path Parameters

proj_id

string<uuid>

required

The project's ID, a UUID. It is not the model's ID.

env

string

required

The environment's ID (a UUID) or its name, such as production. A name matches only a live environment; a deleted environment is reachable by its ID only.

Body

application/json

A merge patch of the environment's settings. Read-only fields (id, project_id, name, revision, created_at, deleted_at, public, node_selector) are accepted only with their current values, so you can send back an object you read.

image

object

The image to run. Send tag, ref, both (they must name the same image), or digest alone. A tag is a model image tag, or a release of the model; a tag wins over a release of the same name. A 12 to 64 character lowercase hex tag that no tag has names the image whose digest it starts. A digest is sha256:<64 hex> or a 12+ character hex prefix. A ref, a digest, or such a hex tag runs the image with no release.

Show child attributes

weights

string | null

A weight set of the project, by sha256:<64 hex> set digest, a weights tag, a release whose bundle is a weight set, or a 12+ character hex prefix. null clears the pin. Omitted keeps the current pin. A string needs weight sets enabled for your account.

resources

object

A merge patch. An absent key keeps its value.

Show child attributes

extra_args

string[]

The full list. [] clears it.

instances

object[]

The full declaration. It replaces the current one.

Show child attributes

variables

object

A merge patch by name. An entry replaces the stored entry whole; null removes it; an absent name keeps it and its pin.

Show child attributes

deployment_strategy

enum<string>

default:ROLLING

How replaced instances roll. Applies to this write only; never inherited.

Available options:

ROLLING,

REPLACE_ALL

interrupt_sessions

boolean

default:false

End live sessions on replaced instances after the replacement. Needs REPLACE_ALL. Applies to this write only.

Response

The environment after the write. revision names the new revision, or the same one when nothing changed.

string<uuid>

required

The environment's ID. It is neither the project's nor the model's ID.

project_id

string<uuid>

required

name

string

required

image

object | null

required

The current image. For production, the deployed release's image. Null for another environment before its first revision.

Show child attributes

weights

object | null

required

The pinned weights. Null when none are pinned.

Show child attributes

resources

object

required

What each instance gets.

Show child attributes

extra_args

string[]

required

Extra arguments passed to the model container.

node_selector

string | null

required

Read-only.

instances

object[]

required

Show child attributes

revision

object | null

required

The current revision. Null before the first revision.

Show child attributes

public

boolean

required

When true, any authenticated caller can open sessions on production. It grants no read. Read-only for customers.

created_at

string<date-time>

required

deleted_at

string<date-time> | null

required

When the environment was deleted. A deleted environment takes no writes.

variables

object

Variables keyed by name. Names use letters, digits, _, -, and ., with no leading digit. Reserved names such as MODEL_NAME and any REACTOR_ name are refused.

Show child attributes

⌘I

curl --request PATCH \
  --url https://api.reactor.inc/projects/{proj_id}/environments/{env} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "image": {
    "tag": "v1.3.0"
  }
}
'

{
  "id": "4b5c6d7e-8f90-4a1b-8c2d-3e4f5a6b7c8d",
  "project_id": "0d3c6f4e-8a1b-4c2d-9e7f-1a2b3c4d5e6f",
  "name": "production",
  "image": {
    "tag": "v1.3.0",
    "digest": "sha256:d138642b1cd5ea5bba6ed5655fa1d7dfced33889d149b094b2c32c32f09ed3da",
    "ref": null
  },
  "weights": null,
  "resources": {
    "accelerators": [
      {
        "type": "NVIDIA_H100",
        "count": 1
      }
    ]
  },
  "extra_args": [],
  "node_selector": null,
  "instances": [
    {
      "count": 3,
      "regions": {
        "prefer": [
          "us-east"
        ]
      }
    }
  ],
  "variables": {
    "LOG_LEVEL": {
      "value": "debug"
    },
    "API_KEY": {
      "secret": "prod-api-key",
      "version_id": "018cc820-e222-7ba6-9f43-7cf0b7e3a112"
    }
  },
  "revision": {
    "number": 4,
    "created_by": {
      "user_id": "9a8b7c6d-5e4f-4a3b-8c2d-1e0f9a8b7c6d"
    },
    "created_at": "2026-10-10T11:16:40Z"
  },
  "public": false,
  "created_at": "2026-10-09T08:53:20Z",
  "deleted_at": null
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

{
  "error": "failed_precondition",
  "reason": "environment_incomplete",
  "message": "environment staging is not complete: set image",
  "missing_fields": [
    "image"
  ]
}

{
  "error": "etag_mismatch",
  "message": "environment staging is at revision 4, not 3"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>",
  "quota_type": "<string>",
  "limit": "<string>",
  "current": "<string>",
  "field": "<string>"
}

{
  "error": "<string>",
  "message": "<string>",
  "resource": "<string>",
  "reason": "<string>"
}

Get started

SDK Reference

CLI Reference

Platform API Reference

Endpoints

Update an environment

Authorizations

Headers

Path Parameters

Body

Response