Core Concept6 min read•Audience: All, Marketers, Developers

Email Platforms Integration Overview

How to use PostBrix email templates with third-party sending platforms, map dynamic variables, and configure mandatory unsubscribe tags.

Key Takeaways

PostBrix is an email production engine, not an ESP. You export HTML/MJML to send through your email service provider.
Different email sending platforms use different templating languages and merge tag delimiters.
You must map PostBrix Handlebars variables to your sending platform’s native syntax before dispatching campaigns.
Ensure you replace sample unsubscribe links with your provider’s mandatory unsubscribe tag.

The Export & Send Workflow#

Because PostBrix is dedicated entirely to template design, compilation, and rendering, your email delivery takes place through a dedicated sending platform or Email Service Provider (ESP).

The standard workflow is:

code

text

1. Design email template in PostBrix
               ↓
2. Export compiled responsive HTML
               ↓
3. Import or paste HTML into your Email Platform
               ↓
4. Map personalization variables to provider tags (e.g. *|FNAME|* or {{ contact.FIRSTNAME }})
               ↓
5. Insert provider's required unsubscribe tag
               ↓
6. Send live test & schedule campaign

Syntax Compatibility Notice

Do not assume your sending platform will automatically recognize PostBrix Handlebars tags (like {{firstName}} or {{#if sale}}). While some modern platforms (like SendGrid or Postmark) support Handlebars, others (like Mailchimp or ActiveCampaign) require specific merge tag syntaxes (*|FNAME|* or %FIRSTNAME%). Review your provider guide below.

Merge Tag Quick Reference Table#

Compare how standard personalization attributes translate across popular email platforms:

Platform	First Name	Email Address	Unsubscribe Link
PostBrix (Default)	`{{firstName}}`	`{{email}}`	`{{unsubscribeUrl}}`
Mailchimp	`*	FNAME	*`	`*	EMAIL	*`	`*	UNSUB	*`
SendGrid	`{{firstName}}`	`{{email}}`	`{{{unsubscribe}}}`
Klaviyo	`{{ person.first_name }}`	`{{ person.email }}`	`{% unsubscribe_link %}`
Brevo (Sendinblue)	`{{ contact.FIRSTNAME }}`	`{{ contact.EMAIL }}`	`{{ unsubscribe }}`
HubSpot	`{{ contact.firstname }}`	`{{ contact.email }}`	`{{ unsubscribe_link }}`
Postmark	`{{firstName}}`	`{{email}}`	`{{{pm:unsubscribe}}}`
Customer.io	`{{ customer.first_name }}`	`{{ customer.email }}`	`{% unsubscribe_url %}`
ActiveCampaign	`%FIRSTNAME%`	`%EMAIL%`	`%UNSUBSCRIBELINK%`
Mailgun	`%recipient.first_name%`	`%recipient.email%`	`%tag_unsubscribe_url%`

Mandatory Legal Footer Requirements#

Under CAN-SPAM (US), GDPR (EU), and CASL (Canada), marketing emails must include:

A clear, functional unsubscribe mechanism (using your ESP's tag).
A valid physical postal address registered to your organization.

Never send an email that lacks an unsubscribe link—most ESPs will refuse to dispatch the message or automatically inject an unstyled default footer at the bottom of your email.

ESP Merge Tag Translation Engine

Select your delivery platform to see the required syntax for personalized fields.

Platform	Email	Conditional Logic	Delivery Notes
PostBrix (Handlebars)	{{email}}	{{#if isVip}}...{{/if}}	Native builder syntax preserved in dynamic HTML export.
Mailchimp	\|EMAIL\|	\|IF:VIP=yes\|...\|END:IF\|	Must use pipe-delimited merge tags. Replace tags after pasting custom HTML.
SendGrid	{{email}}	{{#if isVip}}...{{/if}}	Dynamic Templates support Handlebars directly. Unsubscribe requires triple braces {{{unsubscribe}}}.
Klaviyo	{{ person.email }}	{% if person.vip %}...{% endif %}	Uses Django/Liquid template engine. Profile fields live under person.*.
Brevo (Sendinblue)	{{ contact.EMAIL }}	{% if contact.VIP == "true" %}...{% endif %}	Contact attributes must be uppercase (e.g. FIRSTNAME).
HubSpot	{{ contact.email }}	{% if contact.is_vip %}...{% endif %}	Uses HubL. Ensure CAN-SPAM address tokens are placed in your footer.
Postmark	{{email}}	{{#isVip}}...{{/isVip}}	Supports Mustache syntax mapped to TemplateModel JSON properties.
Customer.io	{{ customer.email }}	{% if customer.plan == "pro" %}...{% endif %}	Liquid syntax. Event data is accessible under event.* and customer data under customer.*.
ActiveCampaign	%EMAIL%	Conditional blocks configured in UI	Percent-delimited tags. Ensure mandatory unsubscribe and address tags are present.
Mailgun	%recipient.email%	Handled via Mailgun template engine or backend render	Supports batch sending with recipient-variables JSON payload.

Frequently Asked Questions

Why does my email provider require their own unsubscribe link?

Sending providers are legally mandated to manage opt-outs and unsubscribe requests. Their custom merge tags generate individualized, single-click unsubscribe URLs that immediately update your suppression lists.

Can PostBrix send campaigns directly to my customer list?

No. PostBrix is strictly an email design, templating, and rendering engine. Email dispatching and deliverability management are handled by your sending provider.

Export

HTML Export

Email Platforms

Mailchimp Integration

Email Platforms

SendGrid Integration

PreviousBefore You Send: 12-Point Checklist NextUsing PostBrix with Mailchimp

The Export & Send Workflow#

Because PostBrix is dedicated entirely to template design, compilation, and rendering, your email delivery takes place through a dedicated sending platform or Email Service Provider (ESP).

The standard workflow is:

code

text

1. Design email template in PostBrix
               ↓
2. Export compiled responsive HTML
               ↓
3. Import or paste HTML into your Email Platform
               ↓
4. Map personalization variables to provider tags (e.g. *|FNAME|* or {{ contact.FIRSTNAME }})
               ↓
5. Insert provider's required unsubscribe tag
               ↓
6. Send live test & schedule campaign

Syntax Compatibility Notice

Merge Tag Quick Reference Table#

Compare how standard personalization attributes translate across popular email platforms:

Platform	First Name	Email Address	Unsubscribe Link
PostBrix (Default)	`{{firstName}}`	`{{email}}`	`{{unsubscribeUrl}}`
Mailchimp	`*	FNAME	*`	`*	EMAIL	*`	`*	UNSUB	*`
SendGrid	`{{firstName}}`	`{{email}}`	`{{{unsubscribe}}}`
Klaviyo	`{{ person.first_name }}`	`{{ person.email }}`	`{% unsubscribe_link %}`
Brevo (Sendinblue)	`{{ contact.FIRSTNAME }}`	`{{ contact.EMAIL }}`	`{{ unsubscribe }}`
HubSpot	`{{ contact.firstname }}`	`{{ contact.email }}`	`{{ unsubscribe_link }}`
Postmark	`{{firstName}}`	`{{email}}`	`{{{pm:unsubscribe}}}`
Customer.io	`{{ customer.first_name }}`	`{{ customer.email }}`	`{% unsubscribe_url %}`
ActiveCampaign	`%FIRSTNAME%`	`%EMAIL%`	`%UNSUBSCRIBELINK%`
Mailgun	`%recipient.first_name%`	`%recipient.email%`	`%tag_unsubscribe_url%`

Mandatory Legal Footer Requirements#

Under CAN-SPAM (US), GDPR (EU), and CASL (Canada), marketing emails must include:

A clear, functional unsubscribe mechanism (using your ESP's tag).
A valid physical postal address registered to your organization.

Never send an email that lacks an unsubscribe link—most ESPs will refuse to dispatch the message or automatically inject an unstyled default footer at the bottom of your email.

Platform

First Name

Unsubscribe Tag

Conditional Logic

Delivery Notes

PostBrix (Handlebars)

{{#if isVip}}...{{/if}}

Native builder syntax preserved in dynamic HTML export.

Mailchimp

*|EMAIL|*

*|IF:VIP=yes|*...*|END:IF|*

Must use pipe-delimited merge tags. Replace tags after pasting custom HTML.

SendGrid

{{#if isVip}}...{{/if}}

Dynamic Templates support Handlebars directly. Unsubscribe requires triple braces {{{unsubscribe}}}.

Klaviyo

{% if person.vip %}...{% endif %}

Uses Django/Liquid template engine. Profile fields live under person.*.

Brevo (Sendinblue)

{% if contact.VIP == "true" %}...{% endif %}

Contact attributes must be uppercase (e.g. FIRSTNAME).

HubSpot

{% if contact.is_vip %}...{% endif %}

Uses HubL. Ensure CAN-SPAM address tokens are placed in your footer.

Postmark

{{#isVip}}...{{/isVip}}

Supports Mustache syntax mapped to TemplateModel JSON properties.

Customer.io

{% if customer.plan == "pro" %}...{% endif %}

Liquid syntax. Event data is accessible under event.* and customer data under customer.*.

ActiveCampaign

%EMAIL%

Conditional blocks configured in UI

Percent-delimited tags. Ensure mandatory unsubscribe and address tags are present.

Mailgun

%recipient.email%

Handled via Mailgun template engine or backend render

Supports batch sending with recipient-variables JSON payload.

Email Platforms Integration Overview

Key Takeaways

The Export & Send Workflow#

Syntax Compatibility Notice

Merge Tag Quick Reference Table#

Mandatory Legal Footer Requirements#

ESP Merge Tag Translation Engine

Frequently Asked Questions

Why does my email provider require their own unsubscribe link?

Can PostBrix send campaigns directly to my customer list?

Related Articles

Email Platforms Integration Overview

Key Takeaways

The Export & Send Workflow#

Syntax Compatibility Notice

Merge Tag Quick Reference Table#

Mandatory Legal Footer Requirements#

ESP Merge Tag Translation Engine

Frequently Asked Questions

Why does my email provider require their own unsubscribe link?

Can PostBrix send campaigns directly to my customer list?

Related Articles