Follow-Up Queue
A sales follow-up tracker app idea: a tiny CRM for founders who sell. Weekend build with Next.js, Supabase and Claude API, for founders doing their own sales.
Why now
Founder-led sales is a constant thread on r/startups and Indie Hackers, and the usual advice is that full CRMs are overkill until the first ten customers. A follow-up queue is the part that matters.
The spec
A queue of every lead you are talking to, ordered by who needs a reply today, with the last message and the next step in one line each.
Build time
WeekendBasic logic / CRUD · Level 2 of 5Audience
Founders doing their own sales.
Stack
- Next.js
- Supabase
- Claude API
Fun factor
Nobody slips through the cracks, and you can see it.
Core features
- Leads with company, stage, and last touch
- Today queue sorted by who is waiting longest
- Next step and due date per lead
- Won, lost, and why
AI features
- Drafts the follow-up from the last message and the next step
- Spots leads that have gone quiet
Stretch goals
- Gmail sync for last touch
- Pipeline value by stage
- Shared queue for a co-founder
First version
A list of leads with a next step and date, and a Today view of who is due.
Build plan
4 milestones, in the order you would build them. Saved ideas get this plan with checkboxes and notes.
The build prompt
Paste this into ChatGPT, Claude, Codex, or Cursor, then build the first version before anything else.
# Build Follow-Up Queue You are a senior full-stack engineer pairing with me on a side project. Build a working first version of the product described below. Read the whole brief before writing any code, then follow "How to work" at the end. ## The idea **Follow-Up Queue.** A queue of every lead you are talking to, ordered by who needs a reply today, with the last message and the next step in one line each. **Why now:** Founder-led sales is a constant thread on r/startups and Indie Hackers, and the usual advice is that full CRMs are overkill until the first ten customers. A follow-up queue is the part that matters. **Who it is for:** Founders doing their own sales **What makes it fun:** Nobody slips through the cracks, and you can see it. ## Scope - **Build time:** Weekend. Size every decision to ship a working first version inside this window. - **Technical ambition:** Level 2 of 5, "Basic logic / CRUD". A few screens over a simple data model with create, read, update, and delete. One lightweight persistence layer, no heavy infrastructure. - **First version only.** Ship the core features below end to end. Stretch goals are listed so you can design around them, not build them. ## Core features (each must work end to end in the first version) 1. Leads with company, stage, and last touch 2. Today queue sorted by who is waiting longest 3. Next step and due date per lead 4. Won, lost, and why ## AI features - Drafts the follow-up from the last message and the next step - Spots leads that have gone quiet How to build them: - Put every model call behind one server-side module with a typed interface, so the provider can change without touching the UI. - Read API keys from environment variables only, and document each one in `.env.example`. - Write prompts as versioned constants with clear instructions and an example of the expected output; parse and validate responses before using them. - Handle timeouts, rate limits, and malformed output with a graceful fallback the user can understand. Stream responses where a wait would exceed a couple of seconds. - Never let a feature depend on the model being perfect. Show the result, let the user edit or retry. ## Stretch goals (later, not in the first version) - Gmail sync for last touch - Pipeline value by stage - Shared queue for a co-founder Leave clean seams for these (a module boundary, a nullable column, a feature flag), but do not implement them unless I ask. ## Tech stack Use exactly: Next.js, Supabase, Claude. Stay on current stable versions, follow each tool's official conventions, and add a library only when the standard library or the chosen stack cannot do the job cleanly. If part of this stack is a poor fit for a specific requirement, say so and propose the smallest change. ## Owner's notes Written by me, the project owner. Treat these as requirements and preferences that override the generated material above when they conflict. The first version should be exactly this, and no bigger: A list of leads with a next step and date, and a Today view of who is due. ## Build plan (with saved progress) 0 of 4 steps complete. Resume at step 1: Lead model. Before you start it, check what is already implemented so you do not repeat finished work. 1. **Lead model** [not started] Company, contact, stage, last touch, next step. 2. **Today queue** [not started] Due and overdue first. 3. **Follow-up drafts** [not started] One click to a reply you can edit. 4. **Won and lost** [not started] Close a lead and note why. ## Definition of done for the first version - [ ] Leads with company, stage, and last touch works end to end, with real data, not a placeholder. - [ ] Today queue sorted by who is waiting longest works end to end, with real data, not a placeholder. - [ ] Next step and due date per lead works end to end, with real data, not a placeholder. - [ ] Won, lost, and why works end to end, with real data, not a placeholder. - [ ] Every screen handles loading, empty, and error states. - [ ] Typecheck, lint, and any tests pass, and the main user flow was exercised by hand. - [ ] A README explains setup, environment variables, and how to run it locally. ## Quality bar - Responsive from a phone to a desktop, keyboard-accessible, semantic HTML, visible focus states, labelled inputs, and sensible contrast. - Loading, empty, and error states for every screen that reads or writes data. Errors say what happened and what to do next. - Validate on the server, never trust the client, and keep secrets in environment variables with a committed `.env.example`. - Type-safe end to end. No `any` without a comment explaining why. - Small, readable modules named after what they do. No premature abstraction, no dead code, no TODOs left for later without a note. - Sensible defaults over settings. If a choice is not in this brief, pick the simplest option that keeps the product coherent and say what you chose. ## How to work 1. **Read, then restate.** Summarize the product in three sentences and list your assumptions. Ask only the questions that block implementation. For everything else, decide and note the decision. 2. **Plan before code.** List the files and modules you will create, in build order, mapped to the core features. If a build plan is included above, use it instead: resume at the first step not marked done and check what already exists before touching it. 3. **Set up.** If a project already exists, inspect its code, instructions, and conventions first and build on them. Otherwise scaffold the stack above with linting, formatting, a typecheck script, `.env.example`, and a README stub. 4. **Model the data first.** Define the types, schema, and any migrations before the UI, so the shape of the product is settled early. 5. **Build in vertical slices.** Finish one core feature end to end (data, logic, UI) before starting the next. Keep the app runnable after every slice and commit each slice with a message that says what changed and why. 6. **Then the interface.** Apply the quality bar above to each screen as it lands, not as a final pass. 7. **Verify.** Run typecheck, lint, and tests. Exercise the main user flow by hand. Check each item in the definition of done and each acceptance criterion. 8. **Report.** Tell me what works, what you tested and how, what is not done, every setup step I must complete myself, and the three most useful next steps. Never claim a service, test, or flow was verified when it was not. If you can edit and run the project, start implementing right after the short plan. If you cannot, give me concrete code and the exact commands to run for the next step. Rules: keep the product name and the scope as written, do not invent features, prefer boring and proven choices, and stop to ask me when a decision would be expensive to reverse.
How to use
- Copy the prompt above.
- Open ChatGPT, Claude, or your AI editor and paste it into a new conversation.
- Build milestone one, run it, then move to the next. Add stretch goals only after the first version works.
Want ideas built around you instead? Generate four from your own interests, time, and stack.
FAQ
Frequently asked questions
Answers on what Follow-Up Queue is, how to build it, and where example ideas come from.
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