Solo founder · United Kingdom · Building in public

I build small SaaS. Solo. From a UK desk.

I am Sal. I run Consent Leads, a reply-system SaaS for UK service businesses. I do the engineering, product, copy, sales, design and ops. The whole stack runs on free tiers and costs less than a weekly Oyster card to operate.

• UK-based, GMT timezone • Full-stack: Python, FastAPI, Cloudflare, Claude API • 6 months shipping

What I do right now

I run Consent Leads. The product is a reply system for UK clinics, salons, dental practices, chiropractors and pilates studios. It reads inbound Instagram DMs, replies in the owner's voice in under 30 seconds, and escalates anything subtle to the owner. Lite tier is £49/mo, no setup fee, cancel anytime. Founding tier with full multi-channel + booking is £1,500 build + £200/mo.

The site is at consentleads.uk. The live demo is at demo.consentleads.uk - message it the way a real customer would and watch it reply in real time.

Receipts

What I have actually shipped, not what I plan to ship.

Live SaaS

Consent Leads

Reply-system SaaS for UK service businesses. Multi-tier (Lite, Concierge, Founding, Custom). Solo-built and run.

Python · FastAPI · Claude API · Stripe · Resend · Cloudflare
Demo platform

Live multi-vertical demo

Prospect-facing demo that loads a different system prompt per vertical (hair, dental, medspa, chiro, pilates). One server, six businesses.

FastAPI · Oracle Cloud ARM · Cloudflare Tunnel
Mobile dashboard

In-house customer dashboard

Magic-link auth, mobile-first conversation review, pause/resume controls, one-tap cancel. Replaces a third-party form tool we deprecated.

HMAC sessions · FastAPI · native HTML/CSS
Outbound engine

Cold-email + sourcing pipeline

Unattended ICP-sourcing agent (Brave + Companies House), opt-out-respecting outbound, multi-tenant reply triage. 800+ sends queued as at-jobs.

Brave API · Companies House API · Resend · Notion CRM
SEO + content

5 blog pillars + 6 vertical landing pages

Programmatic per-vertical SEO under /for/. Comparison pages vs ManyChat and Sprout Social. Lead-magnet calculator with backend playback emails.

Static HTML · JSON-LD · Cloudflare Pages
Infra

Cron-driven ops

Daily sourcing, reply triage, bounce handling, health checks, hot-lead phone alerts (ntfy). Runs unattended on Oracle ARM Always Free.

systemd timers · at-jobs · ntfy.sh

Code (public)

Public repos on github.com/visione4906. Production code, real test suites, MIT-licensed. Not stub demos.

FastAPI auth

fastapi-magic-link-auth

HMAC-signed magic-link auth + session cookies for FastAPI. Single-file Python, no third-party deps, production-grade.

Python · FastAPI · HMAC · pytest
Email shell

email-styles

Brand-matched HTML email shell. Single-file Python, no build step. Works in Outlook, Gmail, Apple Mail with the right plain-text fallback.

Python · HTML email · table layout · inline styles
Stack notes

solo-saas-stack

README-as-portfolio. The exact stack and monthly costs that run a UK SaaS solo for under £40/month. Useful as reference for anyone planning the same.

Oracle Cloud ARM · Cloudflare · FastAPI · Resend
Quant research

polymarket-research-toolkit

Cross-venue arbitrage research. Brownian-motion z-score edge model, fractional Kelly with 6-layer safety caps, live orderbook handling. Paper-trade only.

Python · asyncio · websocket · SQLite
Content pipeline

horror-shorts-pipeline

Faceless YouTube channel pipeline. State-machine driven, idempotent stages, crash-safe resume. Runs unattended on a single consumer GPU. Real production code for a real channel.

Python · SDXL · Whisper · FFmpeg · Telegram

How I operate

  • Ship small. The roadmap stays short because the constraint is the product. One feature done well beats six half-built.
  • Free-tier first. The whole stack runs on Oracle Cloud Always Free, Cloudflare Pages, Resend free tier, and pay-per-token Claude. Total burn is under £40/mo.
  • Talk to customers, then talk to customers, then build. Most of the product design comes from watching friends with service businesses ignore me while replying to DMs.
  • ASCII-only copy. No em-dashes, no ellipsis, no buzzwords. Reads like a human, because one writes it.
  • Boring tech where it counts, novel tech where it pays. JSON files on disk until SQLite breaks. Claude API for the inference layer that actually moves bookings.
  • Build in public with real numbers. Receipts beat narrative.

What I am open to

I am not actively looking for any of these, but the door is open if any of them are a fit.

  • Engineering
    Senior IC / staff engineering roles at AI-first companies. Especially LLM-product teams, developer-tools, or anything where solo full-stack shipping speed matters more than process. UK timezone preferred.
  • Investment
    Angel or pre-seed cheques into Consent Leads. Looking for operator-investors who have run service-business or SMB-SaaS before, not pure financial cheques.
  • Advisory
    Advisory work for other solo SaaS or UK service businesses. Particularly around LLM product integration, Stripe + Cal.com pipelines, and the boring infrastructure that makes solo shipping possible.
  • Co-founder
    Co-founder approaches from operators with a real wedge (existing audience, domain expertise, distribution channel) in a market where reply-system tech extends naturally. I bring engineering + product, you bring market.
  • Press / pod
    Interviews, podcasts, build-in-public spotlights. Happy to talk about the solo-SaaS-on-free-tier stack, the Anthropic API integration patterns, or the anti-platform thesis behind Consent Leads.

Easiest way to reach me is email.

I read everything personally. No assistant, no inbox-zero performance, no auto-responder pretending to be me. If it is interesting, you will hear back the same day.

[email protected] Book 15 minutes on Cal