Convert Single-File Web App to SaaS

Posted 3 weeks ago

Worldwide

Summary

# ACFaultPro — Full Stack SaaS Developer ### Project Overview Fully working web app for AC/HVAC service engineers — diagnostic tool, commissioning calculators, and model-specific technical data. Built as a single HTML file (~6,000 lines), all logic and data working and tested. Needs converting to a hosted SaaS product with auth, subscription billing, and a database, then maintained and expanded ongoing. This is not a design job. UI is built. This is a conversion, hosting, and data expansion role. ----- ### Phase 1 — Convert and Host (Fixed Scope) - **Framework** — React or Next.js. Existing JS logic and data objects preserved exactly. No rewrites. - **Auth** — Clerk or Auth0. Email/password login and account management. - **Billing** — Stripe. Individual (£10/month) and Enterprise (£500/month unlimited seats). Customer Portal for self-service. - **Database** — Supabase or PostgreSQL. User accounts, subscription status, usage logging. - **Hosting** — Vercel or equivalent. Custom domain, SSL, production-ready. - **Admin view** — Active subscribers, revenue, basic usage stats. - **Data integrity** — Diagnostic data must pass an automated verification test confirming it matches the source file exactly. Required before final payment. **Budget: £3,000–5,000. Timeline: 4–6 weeks.** ----- ### Phase 2 — Ongoing Data Expansion (Long-Term) The app has verified diagnostic data for several Daikin platforms. The UK AC market covers 15+ years of installed equipment across 10+ manufacturers. Goal is full coverage of all major platforms. **Each model series requires data from all manual types — not just one document:** - **Service manual** — fault codes with causes and steps, thermistor resistance tables (A and B curves), compressor winding resistances, pressure sensor lookup tables, valve coil resistances, fan motor windings, megger specs - **Installation manual** — pipe sizes, flare torques, factory charge per model, additional charge rate, max pipe lengths, electrical specs, MCB ratings, vacuum/pressure test procedures, field settings, PCB jumper map - **Technical data sheet** — cooling/heating capacities, sound power levels Lw dB(A), operating temperature ranges, SEER/SCOP ratings, dimensions and weights - **Wiring diagrams** — PCB terminal IDs, sensor locations, refrigerant circuit (where available) Each series has 2–4 documents. All must be processed and cross-referenced. Partial entries are flagged in a dataGaps field until remaining manuals are done. **Manufacturers (priority order):** 1. Daikin — VRV III, FTXS/RXS, FTXP/RXP, MXS multi-split, FBQ/FCQ indoor units 1. Mitsubishi Electric — PUZ-ZM, PUHZ-ZRP, PUHZ-P, PURY VRF 1. Toshiba — RAV series 1. Fujitsu — AOYG/AOTG 1. Mitsubishi Heavy Industries — FDC/FDE/FDCW 1. Panasonic, LG, Samsung, Hitachi, Midea/MDV 80–120 documents estimated for full UK coverage. PDFs provided. Each takes 2–5 hours depending on complexity. Paid hourly or per document. Regular weekly commitment required. ----- ### Technical Requirements React/Next.js · Stripe subscriptions · Supabase/PostgreSQL · Vercel deployment · JavaScript/TypeScript · Large structured data files · SaaS subscription products ----- ### About the Data Built over several months from manufacturer service manuals. Not AI-generated. Every value sourced and cited. Must never be modified outside the agreed process. Automated verification runs after every data addition. ----- ### What I’m Looking For Long-term partner for both the SaaS build and ongoing data work. Clear commercial roadmap with a pilot FM company client already confirmed. **Please include:** examples of SaaS products with Stripe billing, your approach to preserving existing JS data during conversion, Phase 1 estimate, and Phase 2 availability. **NDA required before the source file is shared.**

  • Hours to be determined
    Hourly
  • 1-3 months
    Duration
  • Intermediate
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
HTML5
JavaScript
Nice-to-have skills
PHP
Web Design
Activity on this job
  • Proposals:50+
  • Last viewed by client:3 weeks ago
  • Interviewing:
    4
  • Invites sent:
    4
  • Unanswered invites:
    0
About the client
Member since Jun 9, 2026
  • United Kingdom
    3:01 AM
  • Engineering & Architecture
    Small company (2-9 people)

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