From prompt to prototype: a free stack for vibe coders
Turn one small app idea into a testable prototype, with a clear brief, editable components and a sensible backend plan.
A small prototype with one complete user journey and a written test checklist.
The difficult part of an AI-assisted build is often deciding what the first version should do. Start with one person, one problem and one useful outcome. This suggested workflow combines a sketch, a small implementation and a deliberate test. It is a project recipe, not a report of a completed customer build.
Free boundaries before you start
Source checks for this workflow. These notes clarify older catalogue summaries; they do not change your saved toolkit.
Excalidraw · checked 2026-10-13
Free browser whiteboard with local saving and PNG, SVG and editable file exports. The manual guide does not use AI credits. Excalidraw Plus is a separate paid workspace for cloud organisation. The editor software is MIT-licensed; hosting and imported assets have separate terms.
Account requirement not confirmed in this source check.
Supabase · checked 2026-10-13
Free hosted plan: 2 active projects; 500 MB database per project; 1 GB file storage; 50,000 monthly active users; 5 GB egress plus 5 GB cached egress; max storage upload 50 MB. Projects pause after 1 week inactive; automatic backups not included. Hosted plan terms and quotas apply; component licences apply separately to self-hosting.
Account required for this workflow.
A small example to aim for
Pick one small project.
Complete the main action.
See a clear saved state.
FreeStack example output · illustrative, not a provider screenshot or a tested export.
Jump to a step
Write a brief that can say no
Use this structure: “For [person], the app helps with [task]. They enter [input] and receive [result]. Version one will not include [extras].” A simple job tracker might add a job, change its status and show the next action. Leave payments, teams and notifications out until the basic journey works. Keep a list of decisions so later prompts do not quietly reverse them.
Sketch the awkward states
Use Excalidraw to sketch the starting screen, the first successful result and what happens when something fails. Include an empty list and a mistaken input. A quick diagram is enough. If you cannot explain how someone recovers from an error, another polished screen will not solve the gap.
Build one working slice
An AI builder such as Lovable can help produce a first version within its plan limits. Alternatively, work in VS Code and use shadcn/ui components where they suit the project. The component source can be adapted, which also means you need to maintain your changes. Ask for one journey at a time and inspect what changed before requesting the next feature.
Decide what really needs a backend
A shared app needs real storage and access rules. Supabase is a candidate for a small backend, but its free plan has limits and inactive projects can pause. Use sample data during early development. Test that a second account cannot read or change the first account’s private records before involving real users.
Test the result, not the promise
Follow the journey with a fresh account and a small screen. Refresh after saving, enter an invalid value and try opening a direct link. Write down the expected result for each action. Share the prototype as an experiment, with any missing pieces stated clearly. Count a useful completed task as progress, rather than the number of screens generated.
Your workflow, connected.
Follow the steps and carry the output into the next stage. These are suggested handoffs, not automatic integrations.
Provider information
Check current plans and documentation before committing to a workflow.
A couple of useful questions
Do I need all five tools?
No. The sketch, editor and builder are options for different stages. Choose the smallest combination you can understand and maintain.
Can I launch it straight after generation?
Only after checking the actual behaviour, data access and delivery requirements. A convincing preview is not a substitute for those checks.
What would you try?
Share your result or ask a specific question about this workflow.
Join the conversationKeep building
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