PixelGrowth
Cold email infrastructure with a built-in tool suite
Role: Sole engineer — platform architecture, Supabase schema, tool suite, warmup system, deliverability logic. · Updated 2026-09-01
What's actually in it
The problem
Agencies running cold email were stitching together four SaaS subscriptions: one for sending, one for warmup, one for list hygiene, one for copy. Every handoff between them lost data and nobody could attribute a reply back to a subject line.
What I built
- 01Built a 23-route platform covering accounts, campaigns, contacts, pipeline, inbox, unibox, warmup, analytics, workflows, and API docs.
- 02Shipped six first-party tools as their own routes rather than buried features: List Cleaner, Copy Writer, Subject Tester, Send Planner, Audit Report, and Spintax.
- 03Built the warmup system to run against real mailboxes on a dedicated domain, so reputation is built on the same infrastructure that later sends.
- 04Unibox consolidates replies across every connected sending account into one thread view, so a reply is answered from the account it landed on.
- 05Workflow engine with a shared catalog module — the single most-imported file in the graph — so new automation steps register in one place.
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Walkthroughs
The developer POV video is the one worth your time — it walks the dependency graph, the route map, and the data layer rather than clicking through screens.
Engineering decisions
Tools as routes, not modals
Every tool has its own URL. That means an agency can hand a VA a link to the List Cleaner without giving them the campaign dashboard, and it means each tool is independently linkable from the docs.
A single workflow catalog module
components/workflows/lib/catalog.ts is the most-imported file in the codebase. Every workflow step type is declared there once. Adding a step is one entry, not a change across the builder, the runner, and the display layer.
Warmup on owned infrastructure
Warmup mailboxes live on a domain the platform controls. Renting warmup from a third party means your sending reputation is built on someone else's IP pool and disappears when you churn.
The product
Want something built the way PixelGrowth was?
Bring the problem, not a spec. 30-minute call — I'll tell you what it actually takes to build, what I'd cut, and what it costs. No decks, no discovery phase invoice.