Builder-operator

Technical products built,
run, and transferred when ready.

Infrastructure, content, and commerce — deployed solo. Some assets are available to acquire.

12 domains 5 active builds 4 assets for sale All built solo

Active builds

In production. Open to offers.

DueRelay

duerelay.com
Live

Webhook relay and delivery infrastructure. Ingest, deduplicate, and route events with verified receipts.

  • Idempotent ingestion + deduplication
  • Delivery retries with attempt tracking
  • Agent Control Plane in development
  • Live in production, self-hosted on OVH
Infrastructure SaaS Go
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Vhaeon

vhaeon.com
Portfolio

3D knowledge graph. Navigate concepts through semantic connections and temporal correlation.

  • Blank canvas → search → crystallize → weave
  • AI-assisted navigation via local Ollama
  • Semantic axes: time, branch, depth
  • Self-hosted, open for exploration
Research Tools Go Three.js

The New Tradesman

thenewtradesman.com
Live

A publication on recurring failures in software businesses. Patterns, not blame. Judgment and restraint.

  • Pattern-driven editorial format
  • Anonymised case studies across billing, support, trust
  • Ghost CMS, self-hosted on OVH
  • Each post follows a strict pattern schema
Editorial Content Ghost
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Selling Currently

sellingcurrently.com
Live

AI-driven niche content site across commerce verticals. 50+ published articles, SEO-structured.

  • WordPress with REST API automation pipeline
  • 50+ published articles, actively growing
  • Commerce and affiliate-oriented content
  • Programmatic publishing via this server
Content Commerce WordPress
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PlainStatement

plainstatement.com
Live

Free invoice generator with Pro tier. No account required. Clean UX, fast PDF generation, live in production.

  • Live in production with active users
  • Free tier + Pro subscription model
  • PDF generation, international-friendly fields
  • Express.js backend, self-contained deployment
SaaS Billing Node.js
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Available to acquire

Open to offers on all assets below. Scope — domain, code, or both — is listed per asset. Use the offer form or email directly.

ForexFin

forexfin.tech
Available

Webhook-based market alert routing demo. TradingView-compatible event flow with public receipt verification.

Includes: Domain + codebase

  • Alert source → router → destination → receipt
  • TradingView + curl compatible payloads
  • Public receipt endpoint for verification
  • Proof of flow — no active users, idea stage
Fintech Webhooks
Details

CurrentlySelling

currentlyselling.com
Available

Multi-category product discovery site. Built for brand affiliate partnerships and deal-tier navigation.

Includes: Domain + partial static codebase

  • Category-driven static frontend, clean structure
  • Designed for brand affiliate deals (Nike-tier)
  • Monetisation layer not implemented — open foundation
  • Ready to extend or repurpose
Commerce Affiliate Static
Details

BillNode

billnode.app
Available

Shopify DTC margin and break-even ROAS calculator. Single-file, runs in a browser, no data sent.

Includes: Domain + working tool

  • 11 inputs: revenue, COGS, ad spend, refunds, fees, VAT
  • True net margin + break-even ROAS output
  • Verdict badge — profitable or not
  • Self-contained HTML — deploy anywhere or extend
Commerce Tools Shopify
Details

DueBeacon

duebeacon.com
Available

Domain built for reminders, invoice follow-ups, and receivables tracking. Strong metaphor, B2B-ready.

Includes: Domain only

  • Clear meaning on first read — no explanation needed
  • Professional, B2B-friendly naming
  • Natural fit for billing SaaS, fintech, AR tools
  • Was planned as a notification layer on DueRelay
Domain Fintech SaaS
Details

Held domains

Parked. Open to reasonable offers.

  • ixvor.com Short, invented. No category constraint. Five characters, premium feel.
  • nhiom.com Compact, unique. Flexible positioning. Five characters.
  • vhaelum.com Same semantic universe as Vhaeon. Knowledge graph, research, or AI niche.

Build on demand

Everything on this page was built solo — same pace, same standards, available for your project.

[ backend ]

Backend & infrastructure

Event systems, webhook routing, API integrations, deployment pipelines. Go, Node.js, Docker, nginx on self-hosted VPS.

[ content ]

Content automation

WordPress and Ghost setup, REST API publishing pipelines, programmatic content at scale. Structured for SEO from the start.

[ tools ]

SaaS tools & calculators

Single-page utilities, Stripe billing integration, lightweight SaaS products. No-fluff UX, fast to ship.

[ ops ]

Deployment & hosting

Self-hosted VPS setup, nginx, SSL, Docker Compose. Clean, maintainable, no platform lock-in.

Have something in mind? Send a brief.

About

I build and run technical products across infrastructure, content, and commerce. I run everything in production — some for years, some for months. When something reaches its ceiling or finds a better operator, I transfer it.

Everything listed here was built and deployed solo.

12 Domains
5 Active builds
4 For sale

Make an offer

Acquisition, domain transfer, or partnership. Keep it short — what you want and what context you're bringing.

office@constantin-works.com

Opens your email client. No server-side processing.