Deployment Window

Deployment window rules define specific time periods when deployments are allowed or blocked. Using RFC 5545 recurrence rules (rrules), you can create flexible schedules like “weekdays 9am-5pm” or “block deployments during maintenance windows.”

Overview

Why Use Deployment Windows?

Deployment windows help you:

Reduce risk - Only deploy during business hours when teams are available
Coordinate operations - Block deployments during maintenance windows
Meet compliance - Enforce change control windows required by regulations
Protect stability - Prevent deployments during high-traffic periods

Configuration

Terraform
API

resource "ctrlplane_policy" "business_hours_only" {
  name     = "Business Hours Only"
  selector = "environment.name == 'production'"

  deployment_window {
    rrule            = "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0"
    duration_minutes = 480
    timezone         = "America/New_York"
    allow_window     = true
  }
}

curl -X POST https://api.ctrlplane.com/v1/workspaces/{workspaceId}/policies \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Business Hours Only",
    "selector": "environment.name == '\''production'\''",
    "rules": [
      {
        "deploymentWindow": {
          "rrule": "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0",
          "durationMinutes": 480,
          "timezone": "America/New_York",
          "allowWindow": true
        }
      }
    ]
  }'

Properties

deploymentWindow.rrule

string

required

RFC 5545 recurrence rule defining when windows start.

deploymentWindow.durationMinutes

integer

required

Duration of each window in minutes.

deploymentWindow.timezone

string

default:"UTC"

IANA timezone for the rrule (e.g., "America/New_York").

deploymentWindow.allowWindow

boolean

default:"true"

If true, deployments are only allowed during the window. If false, deployments are blocked during the window (deny window).

Understanding rrules

RFC 5545 recurrence rules define repeating patterns. Common components:

Component	Description	Example
`FREQ`	Frequency of recurrence	`DAILY`, `WEEKLY`, `MONTHLY`
`BYDAY`	Days of the week	`MO,TU,WE,TH,FR`
`BYHOUR`	Hours of the day (0-23)	`9` (9am)
`BYMINUTE`	Minutes of the hour	`0`, `30`

Example rrules

Pattern	rrule
Weekdays at 9am	`FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0`
Daily at 2am	`FREQ=DAILY;BYHOUR=2;BYMINUTE=0`
Every Sunday at midnight	`FREQ=WEEKLY;BYDAY=SU;BYHOUR=0;BYMINUTE=0`
First Monday of month	`FREQ=MONTHLY;BYDAY=1MO;BYHOUR=9;BYMINUTE=0`

Window Types

Allow Windows

When allowWindow: true (default), deployments are only allowed during the defined window:

Terraform
API

deployment_window {
  rrule            = "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0"
  duration_minutes = 480
  timezone         = "America/New_York"
  allow_window     = true
}

{
  "deploymentWindow": {
    "rrule": "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0",
    "durationMinutes": 480,
    "timezone": "America/New_York",
    "allowWindow": true
  }
}

Deny Windows (Blackouts)

When allowWindow: false, deployments are blocked during the defined window:

Terraform
API

deployment_window {
  rrule            = "FREQ=WEEKLY;BYDAY=SU;BYHOUR=0;BYMINUTE=0"
  duration_minutes = 360
  timezone         = "America/New_York"
  allow_window     = false
}

{
  "deploymentWindow": {
    "rrule": "FREQ=WEEKLY;BYDAY=SU;BYHOUR=0;BYMINUTE=0",
    "durationMinutes": 360,
    "timezone": "America/New_York",
    "allowWindow": false
  }
}

Common Patterns

Business Hours Only

Allow deployments only during business hours:

resource "ctrlplane_policy" "business_hours_deployments" {
  name     = "Business Hours Deployments"
  selector = "environment.name == 'production'"

  deployment_window {
    rrule            = "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0"
    duration_minutes = 480
    timezone         = "America/New_York"
  }
}

Maintenance Window Blackout

Block deployments during scheduled maintenance:

resource "ctrlplane_policy" "maintenance_blackout" {
  name     = "Maintenance Blackout"
  selector = "environment.name == 'production'"

  deployment_window {
    rrule            = "FREQ=WEEKLY;BYDAY=SU;BYHOUR=2;BYMINUTE=0"
    duration_minutes = 240
    timezone         = "UTC"
    allow_window     = false
  }
}

Weekend Freeze

Prevent deployments over weekends:

resource "ctrlplane_policy" "weekend_freeze" {
  name     = "Weekend Freeze"
  selector = "environment.name == 'production'"

  deployment_window {
    rrule            = "FREQ=WEEKLY;BYDAY=SA;BYHOUR=0;BYMINUTE=0"
    duration_minutes = 2880
    timezone         = "America/New_York"
    allow_window     = false
  }
}

Late Night Deployments Only

For services that require off-peak deployments:

resource "ctrlplane_policy" "off_peak_deployments" {
  name     = "Off-Peak Deployments"
  selector = "deployment.metadata['requires_off_peak'] == 'true'"

  deployment_window {
    rrule            = "FREQ=DAILY;BYHOUR=2;BYMINUTE=0"
    duration_minutes = 180
    timezone         = "America/New_York"
  }
}

Combined with Other Rules

Use deployment windows alongside other policy rules:

Terraform
API

resource "ctrlplane_policy" "production_controlled_release" {
  name     = "Production Controlled Release"
  selector = "environment.name == 'production'"

  any_approval {
    min_approvals = 1
  }

  deployment_window {
    rrule            = "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0"
    duration_minutes = 480
    timezone         = "America/New_York"
  }

  gradual_rollout {
    rollout_type        = "linear"
    time_scale_interval = 300
  }
}

{
  "name": "Production Controlled Release",
  "selector": "environment.name == 'production'",
  "rules": [
    { "anyApproval": { "minApprovals": 1 } },
    {
      "deploymentWindow": {
        "rrule": "FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR;BYHOUR=9;BYMINUTE=0",
        "durationMinutes": 480,
        "timezone": "America/New_York",
        "allowWindow": true
      }
    },
    {
      "gradualRollout": {
        "rolloutType": "linear",
        "timeScaleInterval": 300
      }
    }
  ]
}

Behavior Details

First Deployment Exemption

If a release target has never had a deployment before, deployment window rules are bypassed. This ensures that initial deployments are not blocked by window restrictions.

Window Evaluation

Deployments are evaluated against the current time
If outside an allow window (or inside a deny window), the deployment waits
Ctrlplane automatically re-evaluates when the window state changes, using the computed nextEvaluationTime

Gradual Rollout Integration

When combined with gradual rollout rules:

Allow windows: Rollout start time is adjusted to the next window opening
Deny windows: Individual deployments within a rollout respect the deny period

Timezone Handling

Always specify a timezone for predictable behavior
If omitted, UTC is used
Use IANA timezone names (e.g., “America/New_York”, “Europe/London”)

Best Practices

Environment-Based Windows

Environment	Window Type	Notes
Development	None	Deploy anytime
QA	None	Deploy anytime
Staging	Optional business hours	Mirror production if desired
Production	Strict business hours	When support is available

Recommendations

✅ Use timezones matching your operational team’s location
✅ Account for holidays with deny windows
✅ Provide adequate window duration for rollouts to complete
✅ Combine with approval rules for additional oversight
✅ Test rrule patterns in staging before production
❌ Don’t create windows too narrow for deployments to complete
❌ Don’t forget to account for gradual rollout duration

Next Steps

Policies Overview - Learn about policy structure
Gradual Rollouts - Control deployment pace
Approval - Add human approval gates

Deployment

Job Agents

Policies

Verification

Deployment Window

Overview

Why Use Deployment Windows?

Configuration

Properties

Understanding rrules

Example rrules

Window Types

Allow Windows

Deny Windows (Blackouts)

Common Patterns

Business Hours Only

Maintenance Window Blackout

Weekend Freeze

Late Night Deployments Only

Combined with Other Rules

Behavior Details

First Deployment Exemption

Window Evaluation

Gradual Rollout Integration

Timezone Handling

Best Practices

Environment-Based Windows

Recommendations

Next Steps

Deployment

Job Agents

Policies

Verification

​Overview

​Why Use Deployment Windows?

​Configuration

​Properties

​Understanding rrules

​Example rrules

​Window Types

​Allow Windows

​Deny Windows (Blackouts)

​Common Patterns

​Business Hours Only

​Maintenance Window Blackout

​Weekend Freeze

​Late Night Deployments Only

​Combined with Other Rules

​Behavior Details

​First Deployment Exemption

​Window Evaluation

​Gradual Rollout Integration

​Timezone Handling

​Best Practices

​Environment-Based Windows

​Recommendations

​Next Steps

Overview

Why Use Deployment Windows?

Configuration

Properties

Understanding rrules

Example rrules

Window Types

Allow Windows

Deny Windows (Blackouts)

Common Patterns

Business Hours Only

Maintenance Window Blackout

Weekend Freeze

Late Night Deployments Only

Combined with Other Rules

Behavior Details

First Deployment Exemption

Window Evaluation

Gradual Rollout Integration

Timezone Handling

Best Practices

Environment-Based Windows

Recommendations

Next Steps