Formasty

Hosted no-code form builder for building forms, embedding them, and collecting responses.

KINDA · partial replacement
price $29/mosubscription / year $348estimated build time a weekendreplaced by 0 people

A form builder is one of the most one-shottable categories there is: a schema, a renderer, a responses table, a CSV export. An agent will get you a working multi-step form with conditional fields and an embed snippet in a single session, and for a personal signup form or client intake that is genuinely enough. The gaps are the boring parts nobody thinks about until they bite: email that actually lands in inboxes, spam that gets past a honeypot, file uploads you have to back up, and the dozen integrations that turn a response into a row in someone else's tool. You also inherit uptime, because a form that is down is a lead you never knew existed. Build it if the form is yours and the volume is low; pay if the form is a business process.

Build verification: not recorded. How we judge buildability

What you give up

  • Deliverability: their notification email is warmed and authenticated, your SMTP box is not
  • The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI
  • Template library and builder polish, which is most of what you are paying for in a form tool
  • Payment fields, e-signature, and anything that needs a compliance story like a signed DPA
  • Uptime and CDN edge delivery, so a form on a busy page fails silently when your box does

Why people still pay

Because forms are load-bearing. The moment a form is collecting real leads, applications, or client files, the cost of it quietly breaking exceeds any subscription, and you stop wanting to own the email deliverability, spam waves, and file storage yourself. Paid form tools also sell speed: a decent one gets a branded, conditional, multi-step form live in ten minutes with a template, which is faster than reviewing an agent's output. The self-hosted version wins when it is one form you control on a site you already run.

Your build guide

The stack, security requirements, and agent rules for a focused replacement.

Before you start

  • A supported Node release, PostgreSQL, HTTPS for a shared deployment, and a backup destination. Begin with one workspace and explicit owner/member permissions.
  • Implementation components: Next.js App Router and TypeScript for server-rendered pages and validated mutations. PostgreSQL with Drizzle migrations; Better Auth sessions for a small private workspace. A versioned JSON form schema shared by a controlled builder, public renderer and server-side validator.
  • Scope boundary: Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI
01
Next.js App Router and TypeScript for server-rendered pages and validated mutations.
02
PostgreSQL with Drizzle migrations; Better Auth sessions for a small private workspace.
03
A versioned JSON form schema shared by a controlled builder, public renderer and server-side validator.
04
Domain model: forms, ordered steps, versioned field IDs, branching expressions, responses and notification jobs
engineering roadmap

Implementation plan

1

Phase 1

Scope and fixtures. Implement this bounded workflow: Build a multi-step form editor, publish a responsive share page and provide a safely resizing iframe embed. Show a private response table with filters and a clean CSV export. Record prerequisites, select representative user-owned fixtures and document the unsupported features: Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI

2

Phase 2

Durable model. Model forms, ordered steps, versioned field IDs, branching expressions, responses and notification jobs Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: A form version is immutable after collecting responses; branching must be evaluated on the server as well as in the browser.

3

Phase 3

Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Commit related database changes in one transaction. Use version checks for competing edits and an outbox for external notifications; retry delivery independently of saving the record.

4

Phase 4

Permissions and integration failure. Authorize every record read and mutation on the server using its workspace membership; validate payloads, protect mutations against CSRF, and escape user-authored HTML. Apply per-form submission limits and spam controls; keep responses private and separate public form IDs from management permissions. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results.

5

Phase 5

Portable handoff. Export versioned JSON plus attachments and a readable CSV summary. Restore into a separate database and compare record IDs and attachment checksums before switching. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README.

6

Phase 6

Acceptance scenarios. Skip a conditional step and verify its hidden answers are not accepted; an iframe height message from an unapproved origin is ignored. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder.

the pro prompt
download AGENTS.md
WORKING SLICE
Build a multi-step form editor, publish a responsive share page and provide a safely resizing iframe embed. Show a private response table with filters and a clean CSV export.

Build this scoped Formasty-inspired workflow with a documented data model and visible failure states.

Architecture
- Next.js App Router and TypeScript for server-rendered pages and validated mutations.
- PostgreSQL with Drizzle migrations; Better Auth sessions for a small private workspace.
- A versioned JSON form schema shared by a controlled builder, public renderer and server-side validator.

Prerequisites and limits
A supported Node release, PostgreSQL, HTTPS for a shared deployment, and a backup destination. Begin with one workspace and explicit owner/member permissions.
Outside this release: Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI

Data model and correctness
forms, ordered steps, versioned field IDs, branching expressions, responses and notification jobs
Invariant: A form version is immutable after collecting responses; branching must be evaluated on the server as well as in the browser.
Commit related database changes in one transaction. Use version checks for competing edits and an outbox for external notifications; retry delivery independently of saving the record.

Security and privacy
Authorize every record read and mutation on the server using its workspace membership; validate payloads, protect mutations against CSRF, and escape user-authored HTML. Apply per-form submission limits and spam controls; keep responses private and separate public form IDs from management permissions.

Recovery and export
Export versioned JSON plus attachments and a readable CSV summary. Restore into a separate database and compare record IDs and attachment checksums before switching.

Implementation order
1. Phase 1 — Scope and fixtures. Implement this bounded workflow: Build a multi-step form editor, publish a responsive share page and provide a safely resizing iframe embed. Show a private response table with filters and a clean CSV export. Record prerequisites, select representative user-owned fixtures and document the unsupported features: Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI
2. Phase 2 — Durable model. Model forms, ordered steps, versioned field IDs, branching expressions, responses and notification jobs Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: A form version is immutable after collecting responses; branching must be evaluated on the server as well as in the browser.
3. Phase 3 — Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Commit related database changes in one transaction. Use version checks for competing edits and an outbox for external notifications; retry delivery independently of saving the record.
4. Phase 4 — Permissions and integration failure. Authorize every record read and mutation on the server using its workspace membership; validate payloads, protect mutations against CSRF, and escape user-authored HTML. Apply per-form submission limits and spam controls; keep responses private and separate public form IDs from management permissions. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results.
5. Phase 5 — Portable handoff. Export versioned JSON plus attachments and a readable CSV summary. Restore into a separate database and compare record IDs and attachment checksums before switching. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README.
6. Phase 6 — Acceptance scenarios. Skip a conditional step and verify its hidden answers are not accepted; an iframe height message from an unapproved origin is ignored. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder.

Acceptance
Skip a conditional step and verify its hidden answers are not accepted; an iframe height message from an unapproved origin is ignored.
Use real source data or clearly labeled fixtures. Explain unsupported input and provider failures; do not fabricate analytics, delivery receipts, accuracy claims or security guarantees.

Optional agent guidance
Optional external skill: [web-design-guidelines](https://github.com/vercel-labs/agent-skills/blob/main/skills/web-design-guidelines/SKILL.md) — Review web interfaces for accessibility, keyboard focus, forms, navigation and interaction quality. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Optional external skill: [vercel-composition-patterns](https://github.com/vercel-labs/agent-skills/blob/main/skills/composition-patterns/SKILL.md) — Design reusable React components with composition, context and explicit component variants. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Optional external skill: [supabase-postgres-best-practices](https://github.com/supabase/agent-skills/blob/main/skills/supabase-postgres-best-practices/SKILL.md) — Review PostgreSQL schemas, queries, indexes, pooling, concurrency and row-level security. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission.
Project rule — data model: forms, ordered steps, versioned field IDs, branching expressions, responses and notification jobs
Project rule — preserve this invariant: A form version is immutable after collecting responses; branching must be evaluated on the server as well as in the browser.
Project rule — acceptance evidence: Skip a conditional step and verify its hidden answers are not accepted; an iframe height message from an unapproved origin is ignored.

$ open in your agent (prompt prefilled, you press enter), copy the prompt or copy or download AGENTS.md

prior art · use these instead of building, if you'd rather

No prior-art project is listed yet. Compare the scoped build with the paid product before choosing.

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Questions about Formasty

Can you build your own Formasty with AI?

Partly. A form builder is one of the most one-shottable categories there is: a schema, a renderer, a responses table, a CSV export. An agent will get you a working multi-step form with conditional fields and an embed snippet in a single session, and for a personal signup form or client intake that is genuinely enough. The gaps are the boring parts nobody thinks about until they bite: email that actually lands in inboxes, spam that gets past a honeypot, file uploads you have to back up, and the dozen integrations that turn a response into a row in someone else's tool. You also inherit uptime, because a form that is down is a lead you never knew existed. Build it if the form is yours and the volume is low; pay if the form is a business process.

What does the Formasty build prompt cover?

The prompt starts with this scope: Build a multi-step form editor, publish a responsive share page and provide a safely resizing iframe embed. Show a private response table with filters and a clean CSV export. Full-product capabilities excluded from the comparison include: Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI; Template library and builder polish, which is most of what you are paying for in a form tool. Follow the implementation plan and its prerequisites before expanding the build.

How do I use the prompt, AGENTS.md and agent skills?

Start with the Formasty prerequisites and stack, then copy the prompt into your coding agent. Save the project rules as AGENTS.md in the project root. Linked skills are optional packages or source instructions for specific tasks; review their current contents and install only those matching the chosen stack. A skill does not supply API credentials or verify the finished app.

How long will this Formasty project take?

The catalogue estimate is a weekend for the limited scope. Setup, integration approvals, debugging, deployment and ongoing maintenance can add time. This is an estimate, not a delivery guarantee.

What would I give up by replacing Formasty?

Deliverability: their notification email is warmed and authenticated, your SMTP box is not; The integration shelf: Sheets, Slack, Notion, CRM, Zapier style webhooks with retries and mapping UI; Template library and builder polish, which is most of what you are paying for in a form tool; Payment fields, e-signature, and anything that needs a compliance story like a signed DPA; Uptime and CDN edge delivery, so a form on a busy page fails silently when your box does. Because forms are load-bearing. The moment a form is collecting real leads, applications, or client files, the cost of it quietly breaking exceeds any subscription, and you stop wanting to own the email deliverability, spam waves, and file storage yourself. Paid form tools also sell speed: a decent one gets a branded, conditional, multi-step form live in ten minutes with a template, which is faster than reviewing an agent's output. The self-hosted version wins when it is one form you control on a site you already run.

What price is this guide comparing against?

The recorded Pro plan is $29/mo (monthly per workspace), checked 2026-08-18. Check the linked pricing source before buying. Building your own also has hosting, API and maintenance costs; the recorded amount is not a guaranteed saving.

What can I use instead of building Formasty?

No alternative is listed in this entry yet. That is a gap in this catalogue, not proof that no suitable product exists. Compare the paid product and the proposed scope before committing to a build.

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