Email · checked 2026-10-19

Can I vibecode Missive?

KINDA· weekend project

A shared inbox for a few people is a known shape: sync one or more IMAP mailboxes, thread messages, then add assignments, labels, internal comments and a search index. An agent can build that in a weekend, and FreeScout shows the pattern works. The price you pay in effort is the mail itself: HTML email that renders correctly, IMAP edge cases, OAuth for Gmail and Microsoft 365, plus live collaboration. SMS, WhatsApp and social channels, apps for phone and desktop, and the integration list stay out of reach.

$18/moprice per seat

$216you'd save a year

weekendbuild time

—people replaced it

Before you start

What you need on hand.

DifficultyAdvanced · Real infrastructure or OAuth work.

TimeA weekend; mail edge cases take the longest

Claude Code, Codex or CursorAny of them can run the prompt.
Node.js 22better-sqlite3 compiles a native module, so build tools must be installed.
IMAP and SMTP credentialsApp passwords work with Gmail (with 2-step verification), Fastmail and iCloud; Microsoft 365 needs OAuth, which the prompt leaves out.
A small server with HTTPSA $5 VPS with Caddy is enough for a handful of teammates.

Before you buildMissive has no free plan, only a 30-day trial. If you are the only user, a regular mail client with labels and snooze may already do the job.

1. Install one agent: Claude Code, Codex, Cursor.
2. Make an empty folder and open it in the agent.
3. Paste the prompt below, press enter, and answer its questions as it builds.

The prompt

Build me a small shared inbox for my team to replace Missive. Requirements:

- Node.js 22 + TypeScript: a Fastify server and a React UI built with Vite. `npm start` serves
http://localhost:4400; open browser tabs get live updates over WebSocket (`ws`).
- Mail: up to 3 mailboxes over IMAP (`imapflow`, IDLE) and SMTP (`nodemailer`), host, user and app
password per mailbox in .env. Sync the last 90 days, then follow UID and UIDVALIDITY. Never
delete or move mail on the server.
- Storage: better-sqlite3 in ./data/inbox.db: messages parsed with `mailparser`, conversations
threaded by Message-ID, In-Reply-To and References, attachments in ./data/files/, users,
labels, assignments, comments, drafts, and an FTS5 index over subject, sender and body.
- Inbox: list with unread state, close and reopen, snooze until a time, labels, assignee, and
search with from:, to:, label: and is:unread. HTML mail renders in a sandboxed iframe with remote
images blocked until I click "load images".
- Team: up to 5 users with email and password (`argon2`), roles admin and member; assign a
conversation, @mention a teammate in an internal comment, and show "Sam is replying" while
another user has a draft open.
- Compose: reply, reply all, forward, rich text with TipTap, a signature per user, send later up
to 7 days, 10-second undo, and canned responses with {{first_name}} placeholders.
- Rules: "if sender or subject contains X, then label or assign", evaluated on arrival.
- One organization. No telemetry, local-first: the only outbound calls are IMAP and SMTP.
- Out of scope: SMS, WhatsApp and social channels, calendars, AI features, mobile apps, SSO, OAuth.
- README: app passwords for Gmail, Fastmail and iCloud, that Microsoft 365 needs OAuth and is not
supported, running behind HTTPS with Caddy, backups, and that HTML mail will not render exactly
like Missive.

Opens your agent with the prompt filled in, you press enter. Or copy it and paste it into an empty folder.

Share on X

Max MiskowSponsoredAI agents, automations and MVPs, built for your company.Visit site ›

Then keep going

Next prompts, same folder.

The first prompt builds the core. Run these one at a time in the same folder to grow it into your own Missive.

Extend the shared inbox in this folder. Requirements:

- Make a draft collaborative: edits are sent over the existing WebSocket as small operations
  using `yjs` with a TipTap binding; the draft is saved to SQLite every 5 seconds.
- Show coloured cursors and names for the people in a draft.
- Sending locks the draft for everyone and records who sent it.
- Add a test with two simulated clients editing the same paragraph.
- Update the README.

Add web push to the shared inbox in this folder. Requirements:

- Make the UI an installable PWA and subscribe browsers with `web-push` using VAPID keys from .env.
- Notify on assignment to me, @mentions and replies in conversations I follow; never on every incoming mail.
- A settings page lets each user switch categories off and set quiet hours.
- Remove dead subscriptions when the push service returns 404 or 410.
- Update the README, including the HTTPS requirement.

Add auto-replies to the shared inbox in this folder. Requirements:

- Per mailbox, an optional auto-reply with a subject, body, start and end dates, and a daily send limit.
- Send at most one auto-reply per sender per 7 days; skip mailing lists, noreply addresses and
  anything with Auto-Submitted or Precedence: bulk headers.
- Mark auto-replies with Auto-Submitted: auto-replied and log each one in the conversation.
- Add tests for the skip rules.
- Update the README.

What you lose

SMS, WhatsApp, Messenger and Instagram conversations in the same inbox
Native iOS, Android, macOS and Windows apps
OAuth connections for Gmail and Microsoft 365 that keep working without app passwords
Integrations with CRMs and task tools, and rules beyond simple labelling
Analytics, SLA reports and the AI assistant

Why people still pay

Teams use Missive to stop forwarding emails: one conversation, with comments, assignments and drafts visible to everyone, across email and chat channels, in a client that feels fast on a phone. It costs less than most help desks, and mail stays in Gmail or Outlook, so trying it is low-risk.

Moatcollaboration integrations execution polish

Do the math

Missive or your own copy?

Seats

Over

Your usage

Count my time12h ×$/h

Missive, 1 yr$216

Your own copy, 1 yr$46running + build session

You keep$170pays for itself in the first month

Estimate · A $5 VPS covers a small team; at $18 a user, five people would pay $90 a month for Missive Starter. The build is token usage on your agent plan.

Leaving Missive

Take your data, then cancel.

1 · Take your data out of Missive

1Open Settings > Login & Security > Export your data and click the type you want; you may need to confirm your password.
2Conversations export as a zip with one folder per conversation: a JSON file for the thread and one per message, draft, comment or post, attachments alongside. There is one export per organization, grouped by month.
3Contacts come as one CSV per contact book; responses (canned replies) as HTML files; rules as CSV; comments and address lists as CSV.
4Download links expire after 7 days, each type can be exported once a day, and conversations in the trash are not included.

2 · Cancel Missive

1Open Settings > Billing and click Cancel subscription (the owner only, and from a desktop computer).
2The organization stays active until the end of the billing period, then loses access until you pick a plan again.
3To delete the account as well, remove connected accounts, calendars and integrations, delete the organization, then use Settings > Login & Security > Delete account.

Missive is an email client, not a provider: your mail stays in Gmail, Office 365 or on your IMAP server.
A yearly plan cannot be cancelled mid-cycle or refunded; to go back to monthly, cancel, then subscribe monthly on the day the year ends.
The pricing page says content stays read-only after cancelling, but the billing docs say a paused organization hides conversations and is eventually deleted: export first.
Missive has no free plan to fall back to, so access stops completely when the period ends.

Checked 2026-10-19 against Missive's docs: 1, 2, 3, 4

The escape hatch

Don't feel like building it? These are already free.

FreeScoutOpen sourceAGPL-3.0 PHP help desk and shared mailbox with IMAP sync, assignments, internal notes and paid modules for extras.★ 4.6k · active Oct 2026 · docker to self-host
WebVisit ↗ChatwootOpen sourceMIT-licensed core (an enterprise folder is separately licensed) for shared inbox across email, live chat, WhatsApp and social channels.★ 38k · active Oct 2026 · docker to self-host
Web, iOS, AndroidVisit ↗ZammadOpen sourceAGPL-3.0 ticketing system that turns email, chat and phone into tickets, with an agent web UI and API.★ 6.0k · active Oct 2026 · docker to self-host
WebVisit ↗

All 5 free alternatives to Missive ›

The numbers

Missive pricing

Plan	Monthly	Annual, per month	What you get
Starter	$18/user	$14/user	Up to 5 users, unlimited email history, team spaces and inboxes, conversations and tasks, email, SMS and social accounts, SOC 2 Type II. No integrations, rules, API or AI assistant.
Productive	$30/user	$24/user	Up to 50 users; adds integrations with external tools, rules and automations, basic analytics, API and MCP access, AI assistant.
Business	$45/user	$36/user	Unlimited users; adds SAML SSO, IP restriction, advanced analytics and reporting, personalized team onboarding.

Free tier: No free plan; a 30-day trial of Productive for up to 25 users, no card, showing the last 30 days of history.
Billing: Per active user, monthly or yearly (yearly is 20% off). Monthly can be cancelled any time; the yearly plan is a 12-month commitment with no mid-cycle cancellation or refund. Cards only (no PayPal); prices are in US dollars.
Hidden costs: Each user can connect 5 shared accounts and 10 personal ones; extra shared accounts are $15 a month per 5. US sales tax is added in New York, Ohio and Maryland, and VAT numbers can be entered on invoices. AI runs on Missive credits or your own provider key.
Source: missiveapp.com

Also on the list

Front$35/mo · Customer supportKINDA

Help Scout$30/mo · Customer supportKINDA

Superhuman$30/mo · EmailKINDA

Questions

Missive, briefly

Not answered here? Tell us and we'll add it.

Ask a question ›

Kinda. The core is a weekend build with the prompt on this page, but real gaps remain: SMS, WhatsApp, Messenger and Instagram conversations in the same inbox, Native iOS, Android, macOS and Windows apps.

About $18 a month on the Starter plan per seat, $216 a year (checked 2026-10-19).

SMS, WhatsApp, Messenger and Instagram conversations in the same inbox; Native iOS, Android, macOS and Windows apps; OAuth connections for Gmail and Microsoft 365 that keep working without app passwords; Integrations with CRMs and task tools, and rules beyond simple labelling; Analytics, SLA reports and the AI assistant. If any of those matter to you, keep paying.