You built your project with Claude Code because you wanted agentic AI coding from the terminal. Anthropic's CLI tool handles complex multi-file edits, understands your entire codebase, and works in your existing environment. This is serious vibe coding for developers who live in the terminal. Now you need email infrastructure that matches.

Claude Code users build sophisticated SaaS products. The terminal-based workflow means you are comfortable with APIs and prefer clean REST calls over GUI dashboards. Your email platform should have excellent developer experience, minimal configuration, and work through simple HTTP requests.

This guide covers 12 email marketing tools that work well for Claude Code projects. I prioritized platforms with clean APIs and developer-first approaches. If you are using a different AI code assistant, check out our guides for GitHub Copilot, Cursor, or Windsurf.

Quick Comparison

Tool	Best For	Price at 10k Subs	API Quality	CLI Fit
Sequenzy	SaaS automation	$49/mo	Excellent	Excellent
Resend	Developer DX	$20/mo (volume)	Excellent	Excellent
Postmark	Deliverability	$15/mo (volume)	Excellent	Excellent
Customer.io	Behavioral	$100+/mo	Good	Good
SendGrid	Enterprise	$20-$90/mo	Good	Good
Mailgun	Developer docs	$35/mo	Great	Excellent
Loops	Modern SaaS	$79/mo	Great	Good
Plunk	Open-source	Free-$10/mo	Good	Excellent
AWS SES	Cost	~$1/10k emails	Basic	Good
Buttondown	Newsletters	Free-$29/mo	Good	Good
Userlist	B2B SaaS	$100+/mo	Good	Good
Drip	Events	$39/mo	Good	Good

1. Sequenzy

Price: Free (100 subscribers) / $49/mo at 10,000 subscribers. Transactional emails included at no extra cost.

Claude Code users build sophisticated SaaS products from the terminal. Sequenzy's REST API works perfectly with CLI workflows. No SDK required, just HTTP calls for transactional emails, sequences, and campaigns. The AI sequence generator matches Claude Code's AI-first philosophy.

Built for serious SaaS, not newsletter creators. Advanced sequences with behavioral triggers handle onboarding, trial conversion, and churn prevention. AI generates complete email flows from natural language, matching Claude's AI-native approach.

At $49/mo for 10k subscribers, it is 67% cheaper than Klaviyo and 51% cheaper than Customer.io. Revenue attribution shows which emails drive actual MRR.

Stripe OAuth syncs payment data automatically. Unified transactional + marketing in one platform.

Where it falls short: No SMS. Web dashboard for visual sequence building (though API covers everything).

Best for: Technical founders who want powerful automation without bloated enterprise tools.

2. Resend

Price: Free (3,000 emails/month) / $20/mo for 50,000 emails

Resend offers the best developer experience in transactional email. Clean API, excellent error messages, React Email for templates. For Claude Code users who appreciate well-designed tools, Resend feels right.

Where it falls short: No marketing automation. Transactional only.

Best for: Developers wanting excellent transactional DX.

3. Postmark

Price: From $15/mo for 10,000 emails

Postmark focuses on deliverability. Clean API, fast delivery, strict policies that protect sender reputation.

Where it falls short: Marketing features minimal.

Best for: Critical transactional reliability.

4. Customer.io

Price: From $100/mo for up to 5,000 profiles

Customer.io offers sophisticated behavioral automation. Event-based triggers, multi-channel messaging.

Where it falls short: Expensive. Learning curve.

Best for: Complex behavioral flows.

5. SendGrid

Price: Free (100 emails/day) / $20-$90/mo at scale

SendGrid is enterprise infrastructure. Handles volume, offers dedicated IPs.

Where it falls short: Marketing features basic.

Best for: Enterprise scale.

6. Mailgun

Price: From $35/mo

Mailgun provides developer-focused infrastructure. Excellent documentation, flexible configuration.

Where it falls short: Marketing automation basic.

Best for: Developers wanting detailed control.

7. Loops

Price: Free (1,000 contacts) / $79/mo at 10,000 subscribers

Loops is modern SaaS email. Clean API, focused features.

Where it falls short: Costs more than Sequenzy.

Best for: Modern approach.

8. Plunk

Price: Free (3,000 emails/month) / ~$10/mo for more

Plunk is open-source. CLI vibes, self-hostable, budget-friendly.

Where it falls short: Fewer features.

Best for: Open-source preference.

9. AWS SES

Price: $0.10 per 1,000 emails

AWS SES is cheapest for those with AWS expertise.

Where it falls short: No features. Raw infrastructure.

Best for: Cost optimization.

10. Buttondown

Price: Free (100 subscribers) / $29/mo at 10,000

Buttondown is developer-friendly newsletters. Markdown, API, privacy.

Where it falls short: Not for product email.

Best for: Developer newsletters.

11. Userlist

Price: From $100/mo

Userlist focuses on B2B SaaS with company tracking.

Where it falls short: Expensive. B2B-specific.

Best for: B2B products.

12. Drip

Price: From $39/mo

Drip offers event-based automation.

Where it falls short: E-commerce heritage.

Best for: Event-based flows.

Integration Patterns for Claude Code

Simple curl calls

Claude Code can help you write email integrations. Simple curl for testing:

curl -X POST https://api.sequenzy.com/v1/subscribers \
  -H "Authorization: Bearer $SEQUENZY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"email": "user@example.com", "attributes": {"name": "Alex"}}'

REST API in any language

No SDK dependencies. Just HTTP calls from whatever language you are using.

CI/CD integration

Email APIs work in CI/CD pipelines. Trigger changelog emails from GitHub Actions.

The Bottom Line

For Claude Code projects, Sequenzy offers powerful automation via clean REST API. AI sequence generation matches Claude's AI-native approach. For pure transactional DX, Resend or Postmark. For open-source alignment, Plunk.

See our SaaS email marketing guide for more context.

Check our guides for GitHub Copilot, Cursor, or Windsurf.