A Technical Guide by Leon Basin | basinleon.com
TL;DR
You don’t need a $50k/year tech stack to build serious revenue intelligence. This guide shows you how to assemble a complete GTM system using free tools: n8n for orchestration, free enrichment APIs, local LLMs, and Python glue code. Total cost: $0. Total capability: enterprise-grade.
The Problem: GTM Tools Are a Tax on Growth
Every Series A founder knows this pain: you need revenue intelligence, but the SaaS vendors want $2k/month per seat. By the time you’ve bought:
- CRM ($150/user/mo)
- Enrichment ($500/mo)
- Outreach automation ($200/user/mo)
- Intent data ($1,000/mo)
- Analytics ($300/mo)
…you’re spending $20k/month before closing a single deal.
The alternative: Build the 80% yourself, buy only what you can’t replicate.
The Architecture

The $0 GTM Stack has three layers:
- Signal Ingestion — Google Sheets, Webhooks, RSS feeds, LinkedIn Export
- Enrichment + Scoring — Hunter.io, Clearbit, GitHub API, Local LLM
- Output Layer — Executive Brief, Cold Email, CRM Update, Slack Alert
All orchestrated by n8n — self-hosted, unlimited executions, visual workflows.
Layer 1: Signal Ingestion
What We’re Building
A unified intake layer that captures signals from wherever your prospects live.
Free Tools
| Tool | Purpose | Cost |
|---|---|---|
| Google Sheets | Manual lead entry, imports | Free |
| n8n Webhooks | Automated triggers | Free (self-hosted) |
| RSS Feeds | News/blog monitoring | Free |
| LinkedIn Sales Nav Export | Contact lists | Free with trial |
Code Snippet: URL Ingestion
# logic/ingest.py
import requests
from bs4 import BeautifulSoup
def fetch_text_from_url(url: str) -> str:
"""Ingest article content from any URL for signal extraction."""
response = requests.get(url, timeout=10)
response.raise_for_status()
soup = BeautifulSoup(response.text, 'html.parser')
# Try article tag first, fall back to body
article = soup.find('article')
if article:
return article.get_text(separator='\n', strip=True)
return soup.body.get_text(separator='\n', strip=True)
Layer 2: Enrichment + Scoring
What We’re Building
Automated data enrichment that fills in company/contact details, then scores for priority.
Free APIs
| API | What It Gives You | Free Tier |
|---|---|---|
| Hunter.io | Email finder | 25/mo |
| Clearbit | Company data | Limited lookups |
| GitHub API | Tech stack signals | 5k req/hr |
| Apollo.io | Contact data | 50 credits/mo |
The Scoring Engine
# logic/prompt_engine.py
def score_lead(company_data: dict) -> float:
"""
Score a lead based on signal strength.
Returns 0.0-1.0 confidence score.
"""
score = 0.0
# Firmographic signals
if company_data.get('employee_count', 0) > 50:
score += 0.2
if company_data.get('funding_stage') in ['Series A', 'Series B']:
score += 0.3
# Intent signals
if company_data.get('recent_job_posts', 0) > 5:
score += 0.2
if company_data.get('tech_stack_match', False):
score += 0.3
return min(score, 1.0)
Layer 3: Output Generation
What We’re Building
LLM-powered content generation that turns enriched data into actionable artifacts.
Options (All Free)
| Tool | Use Case | Cost |
|---|---|---|
| Ollama + Llama 3 | Local LLM generation | Free |
| OpenAI (tier 0) | Cloud LLM | $5 free credit |
| Claude (free tier) | Alternative LLM | Limited |
Executive Brief Generator
# logic/generator.py
def generate_executive_brief(company: dict, signals: list) -> str:
"""Generate a McKinsey-style executive brief from signals."""
prompt = f"""
Generate a one-page executive brief for {company['name']}.
Key Signals:
{chr(10).join(f'- {s}' for s in signals)}
Format:
1. Executive Summary (2 sentences)
2. Key Opportunities (3 bullets)
3. Recommended Action (1 sentence)
4. Risk Assessment (1 sentence)
"""
return call_llm(prompt)
The n8n Workflow
Workflow Steps
- Trigger: New row in Google Sheet OR webhook
- Enrich: Call Hunter + Clearbit APIs
- Score: Run Python function node
- Branch: If score > 0.8, proceed
- Generate: Call local LLM for brief
- Output: Update CRM + send Slack alert
Running the Demo
Quick Start (5 minutes)
# Clone the starter repo
git clone https://github.com/BasinLeon/basin-signal-engine
cd basin-signal-engine
# Install dependencies
pip install -r requirements.txt
# Run the pipeline with sample data
python scripts/run_pipeline.py --input master_resume.md
# Output: outputs/brief.json + outputs/audio.mp3
Cost Comparison
| Capability | Enterprise Stack | $0 Stack |
|---|---|---|
| CRM | $150/user/mo | Google Sheets (free) |
| Enrichment | $500/mo | Hunter + Clearbit free tier |
| Automation | $200/user/mo | n8n self-hosted |
| AI Generation | $100/mo | Ollama (free) |
| Total | $950+/mo | $0 |
What’s Next
This stack got me 160% pipeline growth at a Series A startup. The secret wasn’t the tools—it was the architecture: unified signal ingestion, deterministic scoring, and LLM-powered output.
To go deeper:
- GitHub Repo — Full source code
- Live Demo — Try it yourself
- Newsletter — Weekly insights
Questions? DM me on LinkedIn or email lbasin23@gmail.com with subject “Signal received.”

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