> ## Documentation Index
> Fetch the complete documentation index at: https://ahasend.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Template System
> Using templates for personalized emails
# Template System
The AhaSend CLI uses [Jinja2 templating](https://jinja.palletsprojects.com/en/3.1.x/templates/) for creating personalized emails.
## Template Basics
Use double curly braces for variable substitution:
```html theme={null}
Hello {{first_name}}!
Welcome to {{company_name}}.
Your account type is: {{account_type}}
```
## Substitution Types
### Global Substitutions
Applied to all recipients - use for company-wide data:
```json theme={null}
{
"company_name": "ACME Corporation",
"support_email": "support@acme.com",
"year": "2024"
}
```
```bash theme={null}
ahasend messages send \
--from sender@example.com \
--to recipient@example.com \
--html-template template.html \
--global-substitutions company-data.json
```
### Recipient Substitutions
Per-recipient data from CSV/JSON files:
```csv theme={null}
email,first_name,account_type,balance
john@example.com,John,premium,1234.56
jane@example.com,Jane,basic,567.89
```
```json theme={null}
[
{
"email": "john@example.com",
"substitution_data": {
"first_name": "John",
"account_type": "premium",
"balance": 1234.56
}
}
]
```
```bash theme={null}
ahasend messages send \
--from sender@example.com \
--recipients users.csv \
--html-template template.html \
--global-substitutions company-data.json
```
## Basic Examples
### Simple Template
```html theme={null}
Welcome {{first_name}}!
Thank you for joining {{company_name}}.
Your account type: {{account_type}}
Questions? Contact {{support_email}}
```
### Conditional Content
```html theme={null}
Hello {{first_name}}!
{% if account_type == "premium" %}
Thank you for being a Premium member!
{% else %}
Consider upgrading to Premium!
{% endif %}
```
### Lists and Loops
```html theme={null}
Order Confirmation
Thank you, {{customer_name}}!
{% for item in items %}
| {{item.name}} |
{{item.quantity}} |
${{item.price}} |
{% endfor %}
```
## Testing Templates
Test templates using sandbox mode:
```bash theme={null}
ahasend messages send \
--from test@example.com \
--to test@example.com \
--html-template template.html \
--global-substitutions test-data.json \
--sandbox
```
Then check the AhaSend dashboard to see the rendered message.
## Best Practices
1. **Use meaningful variable names**: `{{customer_first_name}}` not `{{fn}}`
2. **Provide default values**: `{{name|default("Friend")}}`
3. **Test with real data**: Use sandbox mode before sending
4. **Keep templates simple**: Complex logic belongs in your application
5. **Global vs recipient data**: Company info in global, personal info per recipient
## Next Steps
* [Learn about batch processing](/cli/batch-processing)
* [Explore Jinja2 documentation](https://jinja.palletsprojects.com/en/3.1.x/templates/)
* [View CLI examples](/cli/examples)