GTM Engineering Pipelines

A code-first GTM engineering portfolio: real, version-controlled signal → route → act pipelines built on Sygnal buyer-intent signals with a 100% free tool stack.

Status: Pipeline A (Signal Router) is runnable end-to-end against Postgres; the competitor/alternative SEO generator is live on Cloudflare Pages.

Architecture (Pipeline A)

  Sygnal webhook                          Sygnal owns scoring.
        │  POST + X-Sygnal-Secret          We consume its verdict:
        ▼                                 score, icp_score, entities,
┌──────────────────────────────┐          competitors, suggested_action.
│  webhook_receiver (FastAPI)  │   verify secret header
│  services/webhook_receiver   │   idempotent insert into raw_events
│                              │   ACK 202, process async
└───────────────┬──────────────┘
                │ normalize → route (pipeline_core)
                ▼
┌──────────────────────────────┐
│  n8n orchestration workflow  │   branch on priority, notify, respond
│  n8n/workflows/…router.json  │
└───────────────┬──────────────┘
                ▼
     Slack/Discord alert · Postgres signal state · event log

Design choices worth talking about in interviews:

• Consume the verdict, don't recompute it. Sygnal already scores intent against an ICP blueprint; this pipeline maps score → priority = score × 10 and routes (pipeline_core/verdict.py). Only the routing logic is ours.
• Verify at the edge. Sygnal sends a static shared secret in X-Sygnal-Secret (a sha256= HMAC is also accepted); compared in constant time (pipeline_core/signature.py).
• Idempotency. raw_events.event_id is the PK; duplicate deliveries are acked, not reprocessed.
• ACK fast, work async. Receiver returns 202 and processes in a background task.
• Event sourcing. pipeline_events is an append-only audit log of every stage.
• Graceful degradation. n8n forward retries with exponential backoff, then dead-letters.
• Enriched routing. entities.competitors triggers a competitive play; suggested_action is carried through to the alert.

Quickstart (free stack)

# 1. Deps
make install              # uv sync --extra dev

# 2. Config
cp .env.example .env      # set SYGNAL_WEBHOOK_SECRET; leave DATABASE_URL blank to start

# 3. Run the receiver (in-memory store until Postgres is up)
make run                  # http://localhost:8080

# 4. Fire a signed sample signal at it
make send-test            # -> 202 {"status":"accepted", ...}

Add Postgres + n8n (both free, Docker):

make up                   # postgres:5433, n8n:http://localhost:5678
make import-workflow      # loads the Pipeline A workflow into n8n

The container Postgres host port is ${POSTGRES_HOST_PORT} (default 5432); set 5433 in .env if you already run Postgres locally.

Expose your machine so Sygnal can reach it (no paid hosting):

make tunnel               # prints https://<random>.trycloudflare.com

Point a Sygnal webhook at https://<random>.trycloudflare.com/webhooks/sygnal, set the same secret in .env, and the flow runs end-to-end. Full setup: docs/SETUP.md. Design notes: docs/ARCHITECTURE.md. Portfolio write-up: docs/CASE_STUDY.md.

SEO generator (acquisition asset)

Turns structured competitor data into static, answer-first comparison pages — the BOFU keywords that convert for a challenger brand:

make seo         # -> seo/site/index.html, alternatives/*.html, vs/*.html, sitemap.xml, llms.txt
make seo-serve   # preview at http://localhost:8090
make seo-deploy  # publish to Cloudflare Pages

Live: https://sygnal-alternatives.pages.dev (Cloudflare Pages).

Content is generated from seo/data.json (never free-written), so every page carries unique facts. Pricing in that file is source-cited (vendor pages + Vendr procurement data, Oct 2026) — re-verify before republishing, since prices change.

Layout

pipeline_core/            shared domain logic (framework-free, unit-tested)
  signature.py            webhook shared-secret (or HMAC) verification
  normalize.py            Sygnal webhook envelope -> NormalizedSignal
  verdict.py              consume Sygnal's score (priority, competitive, ICP match)
  routing.py              bucket + owner + SLA + play
  db.py                   Postgres store + in-memory fallback
services/webhook_receiver/ FastAPI edge service
n8n/workflows/            version-controlled workflow JSON
db/migrations/            append-only event store schema
seo/                      competitor/alternative static-site generator
tests/                    pytest for signature, normalize, verdict, routing, seo
fixtures/, scripts/       sample payload + signed test sender

Roadmap

Pipeline	Scope	Status
A — Signal Router	webhook → verify → normalize → route → n8n notify	✅ runnable
B — Enrichment + scoring	waterfall enrichment (free providers), real firmographic fit, dashboard	⏭️ next
C — Personalization + feedback loop	LLM opener drafts, human review, reply outcomes re-weight scoring	planned
SEO — Competitor/alternative pages	programmatic pages from structured data, free static hosting	✅ live (Cloudflare Pages)

Tool stack (all free / free tier)

n8n (self-hosted) · Cloudflare Tunnel · Supabase/Postgres · HubSpot free CRM · Metabase (self-hosted) · GitHub Actions · Gemini/Groq free LLM tiers · Slack/Discord webhooks · Sygnal.