n8n-nodes-fastmail

n8n is a fair-code licensed workflow automation platform.

Installation
Operations
Credentials
Compatibility
Resources

Installation

Follow the installation guide in the n8n community nodes documentation.

Operations

This package provides:

• Fastmail for structured actions on messages, labels, drafts, and threads.
• Fastmail Trigger for near real-time new-message events via JMAP event stream (SSE with reconnect).

Message Actions

• Add label to message
• Delete a message
• Forward a message
• Get a message
• Get many messages
• Mark a message as read
• Mark a message as unread
• Move a message
• Remove label from message
• Reply to a message
• Send a message

Attachment Support

Attachments are supported as options on existing operations (not as separate actions):

• Upload from input binary properties on:
  • Message Send
  • Message Forward
  • Message Reply
  • Draft Create
  • Thread Reply
• Download to output binary on:
  • Message Get
  • Message Get Many

Label Actions

• Create a label
• Delete a label
• Get label info
• Get many labels

Draft Actions

• Create a draft
• Delete a draft
• Get a draft
• Get many drafts

Thread Actions

• Add label to thread
• Delete a thread
• Get a thread
• Get many threads
• Remove label from thread
• Reply to a message
• Trash a thread
• Untrash a thread

Live options

The node fetches available Fastmail data directly for dropdowns:

• Labels (mapped to Fastmail mailboxes)
• Identities

UI behavior

• Optional fields are hidden by default.
• Reply and forward operations expose per-field auto-fill toggles. Each toggle keeps the current automatic behavior when enabled and reveals the corresponding manual field only when disabled.
• Use Compose Options to enable granular fields like Cc, Bcc, Reply All, Create as Draft, and attachment binary mapping.
• Use Fetch Options to enable granular fields like Search, Read Status, body values, and attachment download settings.
• Mailbox Scope and mailbox selection stay as dedicated top-level fields on Get Many (message/thread) for reliable mailbox picking.
• Invalid option combinations are rejected with explicit errors (for example, Reply All outside auto-filled reply operations or Create as Draft outside reply/forward operations).

Credentials

Use a Fastmail API token with the required scopes for the JMAP methods you call.

OAuth2 readiness

OAuth2 support is prepared in code and can be enabled with a simple toggle.

• Toggle constant:
  • nodes/fastmail/Fastmail.node.ts -> ENABLE_FASTMAIL_OAUTH
  • nodes/fastmail/FastmailTrigger.node.ts -> ENABLE_FASTMAIL_OAUTH
• Current default: false (API token mode only)
• Set to true to expose authentication switch (API Token / OAuth2) in the nodes.

Implemented OAuth2 credential:

• Credential type: Fastmail OAuth2 API
• Authorization URL: https://www.fastmail.com/oauth/authorize
• Token URL: https://www.fastmail.com/oauth/token
• Default scopes: offline_access urn:ietf:params:jmap:core urn:ietf:params:jmap:mail urn:ietf:params:jmap:submission

Reference:

• Fastmail Developer OAuth docs: fastmail.com/dev

Compatibility

Tested with:

• n8n 2.11.0

Resources

• n8n community nodes documentation
• Fastmail Developer API
• JMAP (RFC 8620)
• JMAP Mail (RFC 8621)

Icon Attribution

• Node icon source: Fastmail_icon_2019.svg from Wikimedia Commons.
• Wikimedia marks this file as PD-textlogo (public domain for copyright in many jurisdictions).
• Fastmail name and logo may still be protected by trademark rights.
• Users are responsible for confirming trademark and branding permissions for their use case.

Local development (Docker)

Use the helper script:

./testdata/run.sh

The script starts a node:22-slim container, installs dependencies, builds the node, installs n8n, and starts it on http://localhost:5678.

Local test run (simple Docker setup):

./testdata/run.sh

Prerequisite (once): run npm ci in the project root. The script builds dist, prepares a clean custom package under .testdata/custom, and starts n8nio/n8n.