MailerLite

Promptfree, for everyone, and the only version there is

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Build me email marketing that replaces MailerLite — and be honest about the verdict.

Two things make this ALMOST. **The free tier is generous enough that many senders never pay**, so there may be no money to save at all — check yours first. And **an editor whose output survives Outlook** is a genuinely hard rendering problem that consumes more time than the rest of the application. If you write in Markdown and use one template, this is a fortnight. If colleagues need to drag blocks around, it is not.

STACK
- Node 20+ with Fastify, server-rendered HTML
- SQLite through better-sqlite3, WAL mode
- MJML for the rendering, which exists precisely because hand-writing email HTML is miserable
- A sending provider through its API
- Caddy in front

THE EDITOR PROBLEM
- Outlook for Windows renders with the Word engine: no flexbox, no grid, no background image, unreliable padding, and its own idea of spacing. It is the constraint that decides every design
- MJML compiles a sane block syntax into the table soup that works everywhere. Use it rather than fighting the problem yourself
- A block editor is then a tree of MJML components with a preview. That is buildable — but the preview must be honest, which means rendering in real clients, not in a browser
- Test sends to real addresses across the main providers before every template is finished, and keep a checklist: images blocked, dark mode, Outlook, phone width, plain text
- If nobody else edits your emails, skip all of this and write one good template. That decision halves the project

THE DATA MODEL
- subscribers: id, email, fields_json, status, confirmed_at, unsubscribed_at, bounced_at, complained_at, source, consent_text, consent_at, ip_hash
- groups and segments, the second as saved rules evaluated at send time
- campaigns: id, subject, preheader, mjml_source, body_html, body_text, status, scheduled_for, sent_at, recipient_count
- deliveries: id, campaign_id, subscriber_id, status, sent_at, opened_at, bounced_at, bounce_kind, complained_at — one row per person per campaign, written before sending, which makes a resume exact and a duplicate impossible
- automations and automation_sends, so nobody gets a step twice
- forms and landing_pages, which are just pages with a signup on them
- suppression: email_hash, reason, at — global and permanent

SENDING
- The worker claims a batch with a lease and resumes exactly after a crash
- Rate limited to what the provider accepts, with backoff on throttling
- A test send required before any campaign, and a confirmation showing the recipient count and the segment

DELIVERABILITY
- SPF, DKIM and DMARC on your own sending subdomain, written out in the README
- Warm slowly: hundreds, doubling over weeks. A new domain sending ten thousand on day one stays in spam
- Hard bounces suppressed immediately, complaints permanently and never mailed again
- Watch the complaint rate daily; above a fraction of a percent the provider suspends you
- Suppress anyone who has not opened anything in a very long time — a list of dead addresses is what destroys reputation

THE LIST
- Double opt-in, embeddable forms, honeypot, rate limit per address hash
- The consent sentence stored with its timestamp exactly as shown
- Import with a dry run and a declaration of where the addresses came from
- One-click unsubscribe with no login, plus the List-Unsubscribe headers

REPORTS
- Sent, delivered, opened, clicked, bounced, unsubscribed, per campaign and over time, computed at query time
- Open rate labelled as unreliable; clicks are the number that means something

OPERATIONS
- .env: DATABASE_PATH, BASE_URL, PROVIDER credentials, FROM_ADDRESS, SESSION_SECRET, HASH_SALT
- Migrations on boot, each once; nightly backup off the machine — the list is the asset
- Health endpoint reporting bounce and complaint rates

WHAT MATTERS MOST
Deciding whether you need the drag-and-drop editor. If you do not, this is small and pleasant. If you do, budget most of the project for making its output survive Outlook.