LinkNest — AI Link-in-Bio SaaS with a Concierge That Answers

Overview

LinkNest is a complete link-in-bio SaaS in which every public card has an AI concierge. Owners build a card in a seven-step editor. They teach the concierge from their own notes, files and web pages, then publish at one URL. Visitors ask questions and get answers taken only from that material. If the concierge can't answer, or a visitor asks for a meeting, the request becomes a task in the owner's inbox.

It suits buyers who want to run a creator or small-business SaaS, or rebrand it and resell it. Billing is already wired: visitor chats and knowledge uploads spend credits, and owners buy credits through monthly plans and one-off packs. You get the full source code to self-host, rename and sell.

Features

AI concierge

• Four personas. Lumen the Clarifier, Harbor the Host, Vesper the Editor and Pike the Closer each come with a portrait and instructions, and the owner can edit the greeting.
• Answers from the owner's material. Replies come only from the owner's knowledge. The prompt tells the model to treat uploaded content as data, not as instructions.
• Automatic tasks. Unanswered questions and meeting requests are filed as tasks linked to the conversation.
• Abuse limits. Visitor messages are capped per conversation each minute and per card every ten minutes.
• Out-of-credit handling. When the owner runs out of credits, visitors see a polite "paused" message instead of an error.
• Test your concierge. An owner-side panel shows which sources each test answer drew on.
• Optional AI provider. Uses the xAI Grok API when a key is set. Without a key, it replies from retrieval only.
• On/off switch. Turn the concierge off to get a plain link card.

Knowledge base

• Three ways to add knowledge. Owners can write a note, upload a file or import a link.
• File types. PDF, Word (.docx), text, Markdown, CSV, JSON and HTML, up to 4 MB per file. Content is checked so a file can't pose as another type.
• URL import. Pulls the readable text from a page. From a homepage it can also fetch up to 8 pages on the same site. Private-network addresses are blocked.
• Postgres search. Retrieval uses Postgres full-text search, with heading-aware chunking and duplicate detection. No vector database is needed.
• Identity facts. Details from the card are added to the concierge's knowledge automatically.
• Source management. Search, filter by type, view extracted passages, rename, delete or refresh from the link.
• Plan caps. Storage runs from 25 sources and 10 MB on Free up to 1,000 sources and 1 GB on Scale.

Card builder and design

• Seven-step wizard. Design, Look, Type and color, Profile, Contact, Links, then Concierge and publish.
• Live preview. The preview sits beside the editor on desktop and opens as a bottom sheet on mobile. Changes show immediately, and a short tour guides first-time users.
• 21 layouts. Includes Folio, Split, Portrait, Banner, Glass, Ledger, Magazine, Poster, Ticket and Orbit.
• 12 one-tap looks. Each look sets the background, buttons, palette and fonts together.
• Backgrounds. Solid color, 12 gradient presets with custom colors and direction, or a photo. Photos can be one of 6 built-ins, an upload or an image link, with darken and blur sliders.
• Buttons. 4 fills, 5 shapes and 3 shadow styles, with an option to use one color for every button.
• Type and color. 15 palettes, 4 display fonts and 4 body fonts.
• Wallpaper mode. Extends the card background across the whole page.
• Contact visibility. Phone, email, Instagram, website, X and location can each be hidden without deleting them.
• Dead-link protection. Buttons without a valid URL never appear on the live card.
• Onboarding. New users claim a username with a live availability check, then enter their name, role, goals and preferred visitor action.

Tasks, conversations and meetings

• Task inbox. Meetings and questions sit in separate lists with an answered status. The owner's reply goes back into the visitor's chat.
• Meeting booking. The owner picks a time and a length of 15, 30, 45 or 60 minutes. The booking is confirmed in the conversation.
• Google Calendar sync. Owners can connect Google Calendar. Confirmed meetings then create or update events and invite the visitor when their email is known.
• Calendar fallback. Without Google, each booking gives an .ics file plus Google and Outlook add-to-calendar links.
• Conversations. A searchable list of chats on your card, plus chats you started on other cards.
• Saved cards. Signed-in visitors can bookmark cards and search them later.

Billing and credits

• Credit ledger. A visitor chat or a knowledge upload costs 1 credit. Card editing costs 1 credit per hour of editing. Owners see their balance and recent activity.
• Plans. Free gives 500 welcome credits. Starter is $6 for 800 credits a month, Growth is $12 for 1,600 and Scale is $30 for 4,000. Plan names and prices can be edited in admin.
• Top-up packs. Boost (200 credits for $4), Pack (500 for $8) and Bundle (1,500 for $18), sold through Stripe Checkout.
• Three gateways. Subscriptions work through Stripe, PayPal or Razorpay. Razorpay can charge in INR or USD.
• Verified webhooks. Every gateway's webhook checks the signature. Credit grants are recorded once per billing cycle.
• Stripe setup. Testing the connection creates the plan prices, pack prices and a customer billing portal.

Domains, sharing and accounts

• Custom domains. On paid plans, the card can be served at the root of the owner's own domain. Setup uses CNAME and TXT records and a DNS check.
• Settings. Copy the share URL, change the username and publish or unpublish the card.
• Authentication. Email and password sign-in with 6-digit email verification codes and password reset. Google sign-in is optional.
• Demo account. A one-click demo login opens a pre-filled card.

Admin and SaaS operations

• Admin access. The first account becomes admin, and more can be added through an environment list.
• Overview. Counts of cards, published cards, views, inbox messages and emails.
• Plans editor. Edit names, prices, copy, feature keys and Stripe price IDs.
• People. Assign plans by hand and unpublish cards.
• Finance. Paid subscribers, estimated MRR, a last-30-days total, a payment ledger for all gateways and payout requests.
• Payment settings. Enter Stripe, PayPal, Razorpay and Google OAuth keys, switch test mode and test connections. Secrets stay on the server.
• Brand and SEO. Change the product name, tagline, logo, favicon, SEO title and description, share image and X handle, or hide the site from search engines.
• Export. Download a JSON snapshot of the workspace with payment keys masked.
• Visit tracking. Page views are recorded with traffic source, location, device, browser and the visitor's local hour.

Marketing site

• Public pages. Landing page with FAQ, features page, pricing with checkout, templates gallery and a learn guide.

Extra modules in the codebase

• Server logic without studio screens. These modules have server functions and database tables, and some have tests: live status strip, multi-face pages with weekday schedules, and place commerce (specials and table QR scan tracking). The rest are an AI page co-pilot, tips and products, a link shortener, A/B link title tests, email broadcasts, a caption planner and keyword auto-replies. Their studio routes currently redirect to the card editor, so a developer would need to build the screens to expose them.

Tech stack

• React 19, TanStack Start, Router and Query, Vite 8, Tailwind CSS v4, Radix UI
• Postgres with Kysely and pg in production. Embedded PGLite for local development with no setup.
• Better Auth with email codes, and Nodemailer for sending over SMTP
• Stripe SDK, PayPal and Razorpay REST APIs, and the xAI API
• unpdf, mammoth, Readability and linkedom for reading documents and web pages
• Nitro server output, ready for Vercel or any Node 22+ host
• TypeScript, Zod, ESLint and Prettier, with 100 automated test cases run by node --test

What's included

• Complete application source code
• 21 SQL migration files and a migration script that runs on build
• HTML buyer documentation for install, environment variables, deployment, webhooks and admin
• Brand assets: logo, favicon, share image, the four persona portraits and the landing photos
• Marketing site pages and copy
• Test suite plus browser smoke-test and QA scripts

Requirements and third-party costs

You need a Node.js 22+ host and a Postgres database. Every integration is set through environment variables or the admin console. You create and pay for your own accounts.

• Hosting (required). Vercel or any Node 22+ host.
• Postgres 15+ (required in production). Neon or any Postgres provider.
• Domain name (required in production). Also needed if you offer custom domains to your users.
• SMTP email service (required in production by default). Sends sign-up verification and password-reset codes. You can turn verification off.
• xAI API (optional). Usage-based fees for full AI answers. Without it, the concierge replies from retrieval only.
• Stripe (optional). Needed for credit packs and the billing portal. Per-transaction fees apply.
• PayPal and Razorpay (optional). Extra subscription gateways, each with its own transaction fees.
• Google Cloud OAuth client (optional). For Google sign-in and Calendar sync.
• Resend (optional). Only used by the broadcast module, which has no studio screen yet.

The purchase covers the source code only. Fees for these services are billed by the providers.