Adapter Reference

All available channel adapters, their configuration fields, native bulk support, and channel-specific Metadata keys.

Email

SendGrid 

dotnet add package RecurPixel.Notify.Email.SendGrid

"Email": {
  "Provider": "sendgrid",
  "SendGrid": {
    "ApiKey": "SG.xxxxxxxxxx",
    "FromEmail": "no-reply@yourapp.com",
    "FromName": "Your App"
  }
}
Field Required Description
ApiKey ✅ SendGrid API key (starts with SG.)
FromEmail ✅ Verified sender email address
FromName ❌ Display name for the sender

Payload fields used: To (recipient email), Subject, Body (HTML supported).

Native bulk: ✅ Yes — up to 1,000 recipients per API call. SendBulkAsync uses the SendGrid batch endpoint automatically.

Metadata keys:

Key Description
html Set to "false" to send plain text instead of HTML
reply_to Reply-to email address
categories Comma-separated SendGrid categories for analytics

SMTP 

dotnet add package RecurPixel.Notify.Email.Smtp

"Email": {
  "Provider": "smtp",
  "Smtp": {
    "Host": "smtp.office365.com",
    "Port": 587,
    "Username": "no-reply@yourapp.com",
    "Password": "your-password",
    "UseSsl": true,
    "FromEmail": "no-reply@yourapp.com",
    "FromName": "Your App"
  }
}
Field Required Description
Host ✅ SMTP server hostname
Port ✅ SMTP port (typically 587 or 465)
Username ✅ SMTP authentication username
Password ✅ SMTP authentication password
UseSsl ✅ Enable TLS/SSL
FromEmail ✅ Sender email address
FromName ❌ Sender display name

Native bulk: ❌ No — base class loops single sends with a concurrency cap.

Mailgun 

dotnet add package RecurPixel.Notify.Email.Mailgun

"Email": {
  "Provider": "mailgun",
  "Mailgun": {
    "ApiKey": "key-xxxxxxxxxx",
    "Domain": "mg.yourapp.com",
    "FromEmail": "no-reply@mg.yourapp.com",
    "FromName": "Your App",
    "Region": "us"
  }
}
Field Required Description
ApiKey ✅ Mailgun private API key
Domain ✅ Your verified Mailgun sending domain
FromEmail ✅ Sender email
FromName ❌ Sender display name
Region ❌ "us" (default) or "eu"

Native bulk: ✅ Yes — uses Mailgun’s recipient variables API.

Resend 

dotnet add package RecurPixel.Notify.Email.Resend

"Email": {
  "Provider": "resend",
  "Resend": {
    "ApiKey": "re_xxxxxxxxxx",
    "FromEmail": "no-reply@yourapp.com",
    "FromName": "Your App"
  }
}
Field Required Description
ApiKey ✅ Resend API key
FromEmail ✅ Verified sender email
FromName ❌ Sender display name

Native bulk: ❌ No — base class loops single sends.

Postmark 

dotnet add package RecurPixel.Notify.Email.Postmark

"Email": {
  "Provider": "postmark",
  "Postmark": {
    "ApiKey": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "FromEmail": "no-reply@yourapp.com",
    "FromName": "Your App"
  }
}
Field Required Description
ApiKey ✅ Postmark server API token
FromEmail ✅ Verified sender email
FromName ❌ Sender display name

Native bulk: ✅ Yes — uses Postmark’s batch messages endpoint.

AWS SES 

dotnet add package RecurPixel.Notify.Email.AwsSes

"Email": {
  "Provider": "awsses",
  "AwsSes": {
    "AccessKey": "AKIAIOSFODNN7EXAMPLE",
    "SecretKey": "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY",
    "Region": "us-east-1",
    "FromEmail": "no-reply@yourapp.com",
    "FromName": "Your App"
  }
}
Field Required Description
AccessKey ✅ AWS access key ID
SecretKey ✅ AWS secret access key
Region ✅ AWS region (e.g. us-east-1)
FromEmail ✅ SES-verified sender email
FromName ❌ Sender display name

Native bulk: ✅ Yes — uses the SES bulk email API.

Azure Communication Services Email 

dotnet add package RecurPixel.Notify.Email.AzureCommEmail

"Email": {
  "Provider": "azurecommemail",
  "AzureCommEmail": {
    "ConnectionString": "endpoint=https://youracs.communication.azure.com/;accesskey=xxxxxxxxxx",
    "FromEmail": "DoNotReply@youracs.azurecomm.net",
    "FromName": "Your App"
  }
}
Field Required Description
ConnectionString ✅ Azure Communication Services connection string
FromEmail ✅ Sender email registered in ACS
FromName ❌ Sender display name

Native bulk: ❌ No — base class loops single sends.

SMS

Twilio SMS 

dotnet add package RecurPixel.Notify.Sms.Twilio

"Sms": {
  "Provider": "twilio",
  "Twilio": {
    "AccountSid": "ACxxxxxxxxxx",
    "AuthToken": "xxxxxxxxxx",
    "FromNumber": "+15550001234"
  }
}
Field Required Description
AccountSid ✅ Twilio Account SID
AuthToken ✅ Twilio Auth Token
FromNumber ✅ Your Twilio phone number (E.164 format)

Native bulk: ❌ No — base class loops single sends.

Vonage (Nexmo) SMS 

dotnet add package RecurPixel.Notify.Sms.Vonage

"Sms": {
  "Provider": "vonage",
  "Vonage": {
    "ApiKey": "xxxxxxxxxx",
    "ApiSecret": "xxxxxxxxxx",
    "FromNumber": "YourApp"
  }
}
Field Required Description
ApiKey ✅ Vonage API key
ApiSecret ✅ Vonage API secret
FromNumber ✅ Sender ID or phone number

Native bulk: ✅ Yes — uses Vonage bulk SMS API.

Sinch 

dotnet add package RecurPixel.Notify.Sms.Sinch

"Sms": {
  "Provider": "sinch",
  "Sinch": {
    "ServicePlanId": "xxxxxxxxxx",
    "ApiToken": "xxxxxxxxxx",
    "FromNumber": "+15550001234"
  }
}
Field Required Description
ServicePlanId ✅ Sinch service plan ID
ApiToken ✅ Sinch API token
FromNumber ✅ Sinch virtual phone number

Native bulk: ✅ Yes — uses Sinch batch SMS API.

Plivo 

dotnet add package RecurPixel.Notify.Sms.Plivo

"Sms": {
  "Provider": "plivo",
  "Plivo": {
    "AuthId": "xxxxxxxxxx",
    "AuthToken": "xxxxxxxxxx",
    "FromNumber": "+15550001234"
  }
}
Field Required Description
AuthId ✅ Plivo Auth ID
AuthToken ✅ Plivo Auth Token
FromNumber ✅ Plivo phone number

Native bulk: ❌ No — base class loops single sends.

MessageBird 

dotnet add package RecurPixel.Notify.Sms.MessageBird

"Sms": {
  "Provider": "messagebird",
  "MessageBird": {
    "ApiKey": "xxxxxxxxxx",
    "FromNumber": "YourApp"
  }
}
Field Required Description
ApiKey ✅ MessageBird API key
FromNumber ✅ Sender name or phone number

Native bulk: ❌ No — base class loops single sends.

AWS SNS 

dotnet add package RecurPixel.Notify.Sms.AwsSns

"Sms": {
  "Provider": "awssns",
  "AwsSns": {
    "AccessKey": "AKIAIOSFODNN7EXAMPLE",
    "SecretKey": "wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY",
    "Region": "us-east-1",
    "SenderId": "YourApp"
  }
}
Field Required Description
AccessKey ✅ AWS access key ID
SecretKey ✅ AWS secret access key
Region ✅ AWS region
SenderId ❌ SMS sender ID (alphanumeric, supported regions only)

Native bulk: ✅ Yes — publishes to SNS topic for fan-out.

Azure Communication Services SMS 

dotnet add package RecurPixel.Notify.Sms.AzureCommSms

"Sms": {
  "Provider": "azurecommsms",
  "AzureCommSms": {
    "ConnectionString": "endpoint=https://youracs.communication.azure.com/;accesskey=xxxxxxxxxx",
    "FromNumber": "+18331234567"
  }
}
Field Required Description
ConnectionString ✅ Azure Communication Services connection string
FromNumber ✅ Phone number purchased from ACS (E.164 format)

Native bulk: ✅ Yes — uses ACS SMS batch API, chunks of 100 recipients per call.

MSG91 

dotnet add package RecurPixel.Notify.Sms.Msg91

"Sms": {
  "Provider": "msg91",
  "Msg91": {
    "AuthKey": "xxxxxxxxxxxxxxxxxxxxxxxxxx",
    "SenderId": "NOTIFY",
    "Route": "4"
  }
}
Field Required Description
AuthKey ✅ MSG91 API authentication key
SenderId ✅ Up to 6-character alphanumeric sender ID registered in your MSG91 account
Route ❌ MSG91 route. "4" = transactional (default), "1" = promotional

Payload fields used: To = recipient phone number (digits only, no +). Body = message text.

Native bulk: ❌ No — MSG91 SMS has no batch API. Base class loops single sends with a concurrency cap.

Push Notifications

FCM (Firebase Cloud Messaging) 

dotnet add package RecurPixel.Notify.Push.Fcm

"Push": {
  "Provider": "fcm",
  "Fcm": {
    "ProjectId": "your-firebase-project",
    "ServiceAccountJson": "{ \"type\": \"service_account\", ... }"
  }
}
Field Required Description
ProjectId ✅ Firebase project ID
ServiceAccountJson ✅ Full service account JSON (as a string)

Native bulk: ✅ Yes — uses FCM multicast, up to 500 device tokens per call.

Payload fields: To = device registration token. Subject = notification title. Body = notification body.

Metadata keys:

Key Description
image_url URL of image to show in the notification
click_action Android intent / iOS category
data JSON string of custom key-value data payload

APNs (Apple Push Notification Service) 

dotnet add package RecurPixel.Notify.Push.Apns

"Push": {
  "Provider": "apns",
  "Apns": {
    "KeyId": "XXXXXXXXXX",
    "TeamId": "XXXXXXXXXX",
    "BundleId": "com.yourapp.app",
    "PrivateKey": "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----"
  }
}
Field Required Description
KeyId ✅ APNs auth key ID (from Apple Developer portal)
TeamId ✅ Apple Developer Team ID
BundleId ✅ App bundle identifier
PrivateKey ✅ Contents of the .p8 private key file

Native bulk: ❌ No — APNs is one notification per HTTP/2 request. Base class loops.

Metadata keys:

Key Description
badge Badge count to display on app icon
sound Sound name, or "default"
content_available "1" for silent/background push
mutable_content "1" to allow notification service extension
category APNs category identifier

OneSignal 

dotnet add package RecurPixel.Notify.Push.OneSignal

"Push": {
  "Provider": "onesignal",
  "OneSignal": {
    "AppId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "ApiKey": "xxxxxxxxxx"
  }
}
Field Required Description
AppId ✅ OneSignal App ID
ApiKey ✅ OneSignal REST API key

Native bulk: ✅ Yes — uses OneSignal’s bulk notifications API.

Expo Push 

dotnet add package RecurPixel.Notify.Push.Expo

"Push": {
  "Provider": "expo",
  "Expo": {
    "AccessToken": "xxxxxxxxxx"
  }
}
Field Required Description
AccessToken ❌ Expo access token (required for production apps)

Native bulk: ✅ Yes — uses Expo’s push ticket batch API.

WhatsApp

Twilio WhatsApp 

dotnet add package RecurPixel.Notify.WhatsApp.Twilio

"WhatsApp": {
  "Provider": "twilio",
  "Twilio": {
    "AccountSid": "ACxxxxxxxxxx",
    "AuthToken": "xxxxxxxxxx",
    "FromNumber": "whatsapp:+14155238886"
  }
}
Field Required Description
AccountSid ✅ Twilio Account SID
AuthToken ✅ Twilio Auth Token
FromNumber ✅ WhatsApp-enabled number with whatsapp: prefix

Payload: To must include the whatsapp: prefix (e.g. whatsapp:+919876543210).

Native bulk: ❌ No — Meta messaging policy prohibits bulk unsolicited WhatsApp. Base class loops with rate cap.

Meta Cloud API 

dotnet add package RecurPixel.Notify.WhatsApp.MetaCloud

"WhatsApp": {
  "Provider": "metacloud",
  "MetaCloud": {
    "PhoneNumberId": "1234567890",
    "AccessToken": "EAAxxxxxxxxxxxxx",
    "ApiVersion": "v18.0"
  }
}
Field Required Description
PhoneNumberId ✅ Meta Business phone number ID
AccessToken ✅ Permanent system user access token
ApiVersion ❌ API version (default: v18.0)

Native bulk: ❌ No — Meta policy restricts bulk WhatsApp sends. Base class loops.

Metadata keys:

Key Description
template_name Name of an approved WhatsApp message template
template_language Language code for the template (e.g. en_US)

Vonage WhatsApp 

dotnet add package RecurPixel.Notify.WhatsApp.Vonage

"WhatsApp": {
  "Provider": "vonage",
  "Vonage": {
    "ApiKey": "xxxxxxxxxx",
    "ApiSecret": "xxxxxxxxxx",
    "FromNumber": "+14155550100"
  }
}
Field Required Description
ApiKey ✅ Vonage API key
ApiSecret ✅ Vonage API secret
FromNumber ✅ WhatsApp-enabled number registered with Vonage

Payload fields: To = recipient phone number. Subject and Body are combined as the message text.

Native bulk: ❌ No — Meta policy restricts bulk WhatsApp sends. Base class loops.

MSG91 WhatsApp 

dotnet add package RecurPixel.Notify.WhatsApp.Msg91

"WhatsApp": {
  "Provider": "msg91",
  "Msg91": {
    "AuthKey": "xxxxxxxxxxxxxxxxxxxxxxxxxx",
    "IntegratedNumber": "919876543210",
    "Namespace": "your-waba-namespace"
  }
}
Field Required Description
AuthKey ✅ MSG91 API authentication key
IntegratedNumber ✅ WhatsApp Business number without + (e.g. 919876543210 for +91 98765 43210)
Namespace ❌ WhatsApp Business Account namespace for approved template messages

Payload fields: To = recipient phone number (digits only, no +). Body = message text.

Native bulk: ❌ No — Meta messaging policy restricts bulk WhatsApp sends. Base class loops with rate cap.

Team Collaboration

Slack 

dotnet add package RecurPixel.Notify.Slack

"Slack": {
  "WebhookUrl": "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXX",
  "BotToken": "xoxb-xxxxxxxxxx"
}
Field Required Description
WebhookUrl ✅* Incoming webhook URL
BotToken ✅* Bot token for Bot API (alternative to webhook)

*One of WebhookUrl or BotToken is required.

Payload fields: Body = message text. Subject = optional header block.

Metadata keys:

Key Description
channel Override the target channel (Bot API only)
icon_emoji Emoji to use as the bot avatar (e.g. :robot_face:)
username Override the bot display name
blocks JSON string of Slack Block Kit blocks

Native bulk: ❌ No — one message per webhook call. Base class loops.

Discord 

dotnet add package RecurPixel.Notify.Discord

"Discord": {
  "WebhookUrl": "https://discord.com/api/webhooks/000000000000000000/xxxxxxxxxxxx"
}
Field Required Description
WebhookUrl ✅ Discord webhook URL

Payload fields: Body = message content. Subject = optional embed title.

Metadata keys:

Key Description
username Override the webhook display name
avatar_url Override the webhook avatar image URL
tts "true" to send as text-to-speech
embeds JSON string of Discord embed objects

Native bulk: ❌ No — one message per webhook call.

Microsoft Teams 

dotnet add package RecurPixel.Notify.Teams

"Teams": {
  "WebhookUrl": "https://outlook.office.com/webhook/xxxxxxxx@xxxxxxxx/IncomingWebhook/xxxxxxxxxx/xxxxxxxxxx"
}
Field Required Description
WebhookUrl ✅ Incoming webhook connector URL

Payload fields: Subject = card title. Body = card text content.

Metadata keys:

Key Description
theme_color Hex colour for the card accent bar (e.g. 0076D7)
card_json Full Adaptive Card JSON string (overrides Subject/Body)

Native bulk: ❌ No — one message per webhook call.

Mattermost 

dotnet add package RecurPixel.Notify.Mattermost

"Mattermost": {
  "WebhookUrl": "https://mattermost.yourapp.com/hooks/xxxxxxxxxx",
  "Username": "NotifyBot",
  "Channel": "town-square"
}
Field Required Description
WebhookUrl ✅ Incoming webhook URL from Mattermost integrations
Username ❌ Override the bot display name
Channel ❌ Override the target channel (e.g. town-square)

Payload fields: Subject = bold header. Body = message text. Formatted as Markdown.

Native bulk: ❌ No — one message per webhook call.

Rocket.Chat 

dotnet add package RecurPixel.Notify.RocketChat

"RocketChat": {
  "WebhookUrl": "https://rocketchat.yourapp.com/hooks/xxxxxxxxxx",
  "Username": "NotifyBot",
  "Channel": "#general"
}
Field Required Description
WebhookUrl ✅ Incoming webhook URL from Rocket.Chat administration
Username ❌ Override the bot display name
Channel ❌ Override the target channel (e.g. #general)

Payload fields: Subject = bold header. Body = message text. Formatted as Markdown.

Native bulk: ❌ No — one message per webhook call.

Social & Messaging

Telegram 

dotnet add package RecurPixel.Notify.Telegram

"Telegram": {
  "BotToken": "123456789:ABCdefGHIjklMNOpqrsTUVwxyz",
  "ChatId": "-1001234567890"
}
Field Required Description
BotToken ✅ Telegram Bot API token from @BotFather
ChatId ✅ Default target chat/group/channel ID

Payload fields: Body = message text. HTML and Markdown supported via Metadata.

Metadata keys:

Key Description
chat_id Override the default ChatId for this message
parse_mode "HTML" or "MarkdownV2"
disable_notification "true" to send silently
reply_to_message_id Message ID to reply to

Native bulk: ❌ No — per-user DMs loop. Channel broadcasts use a single chat_id.

Facebook Messenger 

dotnet add package RecurPixel.Notify.Facebook

"Facebook": {
  "PageAccessToken": "EAAxxxxxxxxxxxxx",
  "ApiVersion": "v18.0"
}
Field Required Description
PageAccessToken ✅ Facebook Page access token
ApiVersion ❌ Graph API version (default: v18.0)

Payload fields: To = recipient’s Facebook page-scoped user ID (PSID). Body = message text.

Native bulk: ❌ No — Messenger API is per-user. Base class loops.

LINE 

dotnet add package RecurPixel.Notify.Line

"Line": {
  "ChannelAccessToken": "xxxxxxxxxx",
  "ChannelSecret": "xxxxxxxxxx"
}
Field Required Description
ChannelAccessToken ✅ LINE Messaging API channel access token
ChannelSecret ✅ LINE channel secret

Payload fields: To = LINE user ID. Body = message text.

Native bulk: ❌ No — per-user messages loop. Use LINE broadcast endpoint for channel-wide pushes via Metadata.

Viber 

dotnet add package RecurPixel.Notify.Viber

"Viber": {
  "AuthToken": "xxxxxxxxxx",
  "SenderName": "Your App",
  "SenderAvatar": "https://yourapp.com/avatar.png"
}
Field Required Description
AuthToken ✅ Viber service auth token
SenderName ✅ Sender display name (max 28 characters)
SenderAvatar ❌ URL to sender avatar image

Payload fields: To = Viber user ID. Body = message text.

Native bulk: ❌ No — base class loops.

In-App

InApp (Hook-Based) 

dotnet add package RecurPixel.Notify.InApp

The InApp channel does not call an external API. It calls your hook with the payload — you define what “in-app delivery” means for your system.

"InApp": {
  "Enabled": true
}

options.InApp.OnDeliver(async payload =>
{
    await db.InAppNotifications.AddAsync(new InAppNotification
    {
        UserId    = payload.Metadata.GetValueOrDefault("user_id")?.ToString(),
        Title     = payload.Subject,
        Body      = payload.Body,
        CreatedAt = DateTime.UtcNow,
        IsRead    = false
    });
    await db.SaveChangesAsync();
});

You own the schema, the table, and the read/unread logic. We call your hook.

Native Bulk Support Summary

Channel Provider Native Bulk Limit
Email SendGrid ✅ 1,000/call
Email AwsSes ✅ Batch API
Email Postmark ✅ Batch endpoint
Email Mailgun ✅ Recipient variables
Email AzureCommEmail ❌ Loop
Email Resend ❌ Loop
Email SMTP ❌ Loop
SMS Twilio ❌ Loop
SMS Vonage ✅ Bulk SMS API
SMS AwsSns ✅ Topic publish
SMS AzureCommSms ✅ 100/call
SMS Sinch ✅ Batch SMS API
SMS MSG91 ✅ Batch SMS API
SMS Plivo ❌ Loop
SMS MessageBird ❌ Loop
Push FCM ✅ 500 tokens/call
Push APNs ❌ Loop
Push OneSignal ✅ Bulk API
Push Expo ✅ Batch tickets
WhatsApp Twilio, MetaCloud, Vonage, MSG91 ❌ Loop (Meta policy)
Slack — ❌ Loop
Discord — ❌ Loop
Teams — ❌ Loop
Mattermost — ❌ Loop
Rocket.Chat — ❌ Loop
Telegram — ❌ Loop (DMs)
Facebook — ❌ Loop
LINE — ❌ Loop
Viber — ❌ Loop

Adapters without native bulk use the base class loop with a configurable concurrency cap (default: 10 concurrent). Configure via BulkOptions.ConcurrencyLimit in appsettings.json.