Skip to main content
Carrier is configured entirely via environment variables with the CARRIER_ prefix. All configuration settings are defined when starting the application.

​
SQS Configuration

Settings for connecting to and receiving messages from Amazon SQS.
​
CARRIER_SQS_ENDPOINT
string
required
The endpoint for the SQS service. For AWS, use regional endpoints like https://sqs.us-west-2.amazonaws.com.For local development with SQS-compatible services, use custom endpoints like http://sqs:9324.See AWS SQS Service Endpoints for official endpoints.
​
CARRIER_SQS_QUEUE_NAME
string
required
The name of the SQS queue to receive messages from.Example: carrier-demo or my-webhook-queue
​
CARRIER_SQS_BATCH_SIZE
integer
default:"1"
The number of messages each SQS receiver will request from SQS in a single batch.Valid range: 1-10 (SQS maximum)Note: All webhooks are transmitted one message per HTTP request, regardless of batch size.Example: 10 (request maximum messages per poll)
​
CARRIER_SQS_RECEIVERS
integer
default:"1"
The number of concurrent SQS receivers requesting messages from SQS.Each receiver runs independently and polls the queue in parallel.Example: 3 (run three concurrent receivers)
​
CARRIER_SQS_RECEIVER_WORKERS
integer
default:"1"
The number of concurrent workers transmitting messages as webhooks for each receiver.Common pattern: Set this equal to CARRIER_SQS_BATCH_SIZE to transmit all messages in a batch in parallel.Example: 10 (process all messages in batch concurrently)

​
Webhook Configuration

Settings for transmitting messages to webhook endpoints.
​
CARRIER_WEBHOOK_ENDPOINT
string
default:"http://localhost:9000"
The full URL where webhooks will be sent via HTTP POST.Include the complete path: protocol, host, port, and path.Examples:
  • http://localhost:9000/webhook
  • http://worker:8080/v1/events
  • https://api.example.com/webhooks/receive
​
CARRIER_WEBHOOK_REQUEST_TIMEOUT
duration
default:"60s"
The timeout for webhook HTTP requests.Uses Go’s duration format. See time.ParseDuration.Examples:
  • 30s (30 seconds)
  • 2m (2 minutes)
  • 500ms (500 milliseconds)
​
CARRIER_WEBHOOK_DEFAULT_CONTENT_TYPE
string
default:"application/json"
The default Content-Type header value for webhook requests.This can be overridden per-message using the Body.ContentType SQS message attribute.Examples:
  • application/json
  • application/xml
  • text/plain
​
CARRIER_WEBHOOK_TLS_INSECURE_SKIP_VERIFY
boolean
default:"false"
When set to true, disables TLS certificate verification for HTTPS webhook endpoints.Warning: Only use this for development/testing. Never use in production.Example: true

​
Health Check Configuration

Settings for monitoring webhook endpoint availability.
​
CARRIER_WEBHOOK_HEALTH_CHECK_ENDPOINT
string
When set, enables health check functionality for the webhook endpoint.Carrier will wait for this endpoint to be online before processing messages. If the endpoint goes offline, Carrier will exit.Benefits:
  • Prevents message failures during webhook startup
  • Avoids unnecessary dead letter queue messages
  • Enables automatic pod restarts in Kubernetes
Example: http://worker:9000/health
​
CARRIER_WEBHOOK_HEALTH_CHECK_INTERVAL
duration
default:"60s"
The time interval between health checks.Uses Go’s duration format.Example: 30s (check every 30 seconds)
​
CARRIER_WEBHOOK_HEALTH_CHECK_TIMEOUT
duration
default:"10s"
The timeout for each health check request.Example: 5s (timeout after 5 seconds)
​
CARRIER_WEBHOOK_OFFLINE_THRESHOLD_COUNT
integer
default:"5"
The number of consecutive failed health checks before the webhook is determined to be offline.When this threshold is reached, Carrier will exit.Example: 3 (exit after 3 failed checks)

​
Logging Configuration

Settings for log output and formatting.
​
CARRIER_ENABLE_COLORIZED_LOGGING
boolean
default:"false"
When set to true, enables colorized log messages.Useful for local development in terminals or Docker environments.In production, use false for JSON-formatted logs.Example: true
​
CARRIER_ENABLE_STAT_LOG
boolean
default:"false"
When set to true, enables periodic statistics log messages.Logs include:
  • Number of active goroutines
  • Memory usage
Example: true
​
CARRIER_STAT_LOG_TIMER
duration
default:"120s"
The interval between statistics log messages (when CARRIER_ENABLE_STAT_LOG is enabled).Example: 60s (log stats every minute)

​
Example Configurations

​
Local Development

Minimal configuration for local development with Docker Compose: 
CARRIER_WEBHOOK_ENDPOINT=http://worker:9000/webhook
CARRIER_SQS_ENDPOINT=http://sqs:9324
CARRIER_SQS_QUEUE_NAME=default
CARRIER_ENABLE_COLORIZED_LOGGING=true

​
Production Kubernetes

Optimized configuration for production deployment: 
# SQS Configuration
CARRIER_SQS_ENDPOINT=https://sqs.us-west-2.amazonaws.com
CARRIER_SQS_QUEUE_NAME=carrier-production
CARRIER_SQS_BATCH_SIZE=10
CARRIER_SQS_RECEIVERS=3
CARRIER_SQS_RECEIVER_WORKERS=10

# Webhook Configuration
CARRIER_WEBHOOK_ENDPOINT=http://localhost:9000/v1/events
CARRIER_WEBHOOK_REQUEST_TIMEOUT=30s
CARRIER_WEBHOOK_DEFAULT_CONTENT_TYPE=application/json

# Health Check
CARRIER_WEBHOOK_HEALTH_CHECK_ENDPOINT=http://localhost:9000/health
CARRIER_WEBHOOK_HEALTH_CHECK_INTERVAL=30s
CARRIER_WEBHOOK_OFFLINE_THRESHOLD_COUNT=3

# Logging
CARRIER_ENABLE_STAT_LOG=true
CARRIER_STAT_LOG_TIMER=60s

​
High Throughput

Configuration for processing large message volumes: 
CARRIER_SQS_ENDPOINT=https://sqs.us-west-2.amazonaws.com
CARRIER_SQS_QUEUE_NAME=high-volume-queue
CARRIER_SQS_BATCH_SIZE=10
CARRIER_SQS_RECEIVERS=5
CARRIER_SQS_RECEIVER_WORKERS=10
CARRIER_WEBHOOK_ENDPOINT=http://worker:8080/process
CARRIER_WEBHOOK_REQUEST_TIMEOUT=15s
This configuration creates 5 receivers, each requesting 10 messages at a time, with 10 workers per receiver transmitting messages in parallel (50 concurrent webhook requests maximum).
Performance Tip: Setting CARRIER_SQS_RECEIVER_WORKERS equal to CARRIER_SQS_BATCH_SIZE allows all messages in a batch to be transmitted concurrently, maximizing throughput.

Build docs developers (and LLMs) love

Get started for freeTalk to us