# How to Vibe Code Your Own Gusto (and Stop Paying for It) > Payroll, HR, Benefits. Simplified. - Site: https://gusto.com - Category: Payroll & HR SaaS - Verdict: **Serious undertaking** (45/100 vibecodeable) - Estimated effort: 4-6 weeks of intensive development for the mock UI and calculation engine ## Verdict You must keep paying for Gusto unless you are building a simulated mock payroll ledger for educational tinkering, because you cannot legally or programmatically self-file multi-state federal and local payroll taxes. Building a local simulator that mimics Gusto's UI, gross-to-net salary math, and employee onboarding flows is an interesting weekend project, but it falls apart the second actual money and tax remittances are involved. An AI coding agent can easily build the Next.js database CRUD, the employee self-service portal, and basic salary calculators. However, it will completely stall on real-world NACHA file generation, automated state tax filings, and handling changing federal withholding tables without breaking compliance laws. ### What you can't replicate - Official legal status as a payroll service bureau and tax filer with federal and state agencies - Licensed insurance brokerage partnerships and carrier integrations - Accredited ACH money transmitter infrastructure and banking risk guarantees ## What it does All-in-one cloud software platform for small and medium-sized businesses to manage payroll, employee benefits, tax compliance, time tracking, and HR onboarding. ### Core features - Company and employee profile onboarding - W-2 and 1099 contractor payment ledger - Federal, state, and local payroll tax calculation logic - Time tracking and PTO request/approval workflow - Benefits administration dashboard (health insurance and 401k placeholders) - Employee self-service portal for paystubs and tax docs - Employer run-payroll wizard with gross-to-net math ## The business ### Pricing - Contractor Only: $35/mo + $6/contractor - Simple: $49/mo + $6/person - Plus: $80/mo + $12/person - Premium: $180/mo + $22/person ### Funding $750M raised. - Seed / YC (2012) - Series A, B, C, D (2014-2019) - Series E & Extension (2021-2022) Investors: Y Combinator, General Catalyst, Kleiner Perkins, T. Rowe Price, CapitalG, Fidelity Founded 2011. Team size: 3,000+. ## The hard parts - Dynamic multi-jurisdiction tax calculation engine across thousands of federal, state, and local rates - ACH money movement risk controls, ledger accuracy, and NACHA file generation - Strict data privacy, encryption, and compliance architecture for SSNs and banking details - State insurance broker licensing rules and carrier API integration pipelines ## How to vibe code Gusto ### Prerequisites - Node.js (Free): Required runtime for executing the Next.js framework locally. - GitHub (Free): Source code repository and deployment bridge for your app. ### Recommended AI tools - Claude Code: Best-in-class terminal agent for scaffolding complex multi-file database schemas and calculation logic. ### Stack - Frontend: Next.js with Tailwind CSS and shadcn/ui - Backend: Next.js Server Actions and API Routes - Database: Turso (SQLite at the edge for zero-config relational storage) - Auth: better-auth - Payments: Stripe (mocked for demo ledger flow) - Other: Resend for email notifications, Zod for payroll math and input validation ### Hosting - Vercel (Hosting the Next.js frontend and serverless backend actions): $0/mo (Hobby tier) - Turso (Serverless SQLite database storage for companies, employees, and pay runs): $0/mo (Free tier) ### Build guide 1. **Project Scaffolding & Database Schema** — Initialize a Next.js project with Tailwind CSS, configure Turso database connectivity, and establish core tables for companies, employees, pay_schedules, and payroll_runs. ``` Create a new Next.js project with TypeScript, Tailwind CSS, and App Router. Set up Turso with Drizzle ORM. Define the relational database schema in TypeScript for a payroll application: companies (id, name, ein, address), employees (id, company_id, first_name, last_name, ssn_encrypted, hourly_rate, salary, employment_type 'W2'|'1099', bank_routing, bank_account), payroll_runs (id, company_id, pay_period_start, pay_period_end, status), and pay_stubs (id, payroll_run_id, employee_id, gross_pay, federal_tax, state_tax, fica_tax, net_pay). Ensure strict TypeScript types and provide an initial migration script. ``` 2. **Authentication & Company Setup Wizard** — Integrate better-auth for secure user login and implement a multi-step company onboarding wizard to collect federal EIN, address, and bank details. ``` Configure better-auth in the Next.js app supporting email/password authentication. Build a multi-step onboarding wizard UI using React, Tailwind CSS, and shadcn/ui components where a newly registered admin inputs their company details (Name, EIN, business address) and links a primary funding bank account (routing number, account number). Save these records securely to the Turso database using server actions with Zod input validation. ``` 3. **Employee Directory & Self-Onboarding** — Build an employee management dashboard and a shareable self-onboarding link where workers input their personal details, tax withholding preferences, and direct deposit info. ``` Create an employee management dashboard view listing all company workers with their active status, salary type, and payment details. Add a form to manually add an employee or generate a unique onboarding token link. Build a secure public-facing self-onboarding form route where invited employees enter their W-4 withholding data (filing status, allowances), address, and direct deposit routing details, updating their record in the database. ``` 4. **Gross-to-Net Payroll Calculation Engine** — Implement a deterministic payroll calculation engine that computes gross pay, federal income tax, FICA (Social Security and Medicare), and state tax estimates. ``` Write a robust payroll calculation utility in TypeScript that takes a company's active employee list and pay period parameters, then computes gross-to-net paychecks. Implement standard US payroll math formulas for 2026: FICA (6.2% Social Security up to wage base limit, 1.45% Medicare), federal income tax estimation brackets based on W-4 status, and a flat 5% mock state tax. Generate detailed paystub breakdowns showing gross pay, employee deductions, employer payroll tax contributions, and net pay. ``` 5. **Run Payroll Wizard & Ledger Ledger** — Build the multi-step employer 'Run Payroll' workflow that previews calculations, simulates money movement, and records historical pay runs. ``` Build an interactive 'Run Payroll' wizard flow in Next.js. Step 1: Select pay period dates and review employee hours or salaries. Step 2: Preview the calculated gross-to-net totals, total company cash requirement (net pay + employer taxes), and itemized deductions. Step 3: Confirmation button that executes a database transaction recording the payroll run and generating immutable paystub records for each employee. Display a success screen with a summary ledger. ``` 6. **Employee Self-Service Portal & Paystubs** — Create a dedicated worker portal view where employees can sign in, inspect past paystubs, view historical earnings, and download PDF summaries. ``` Build an employee self-service dashboard accessible via separate role permissions. Employees should be able to view their personal profile, review a chronological list of all issued paystubs across payroll runs, inspect year-to-date (YTD) earnings and tax withholdings, and view their direct deposit banking settings. Include a button to download a printable HTML/CSS paystub breakdown statement. ``` ### Cost vs paying **Starting costs (one-time):** - Domain Name (optional): $12/yr - Total: ~$12 one-time **Ongoing costs (monthly):** - Vercel + Turso: $0/mo - Total: $0/mo - Paying for the SaaS instead: $49/mo + $6/person (~$97/mo for 8 people) - Build time: 40-60 hours - AI tool credits: $20 (Claude Pro) - Break-even: Instant (for mock use only; real payroll compliance cannot be self-hosted) ## Sources - [Gusto Official Website](https://gusto.com) - [Tracxn - Gusto Company Profile](https://tracxn.com) - [PitchBook - Gusto Profile & Financing Data](https://pitchbook.com)