competitive-intel

Tech Stack Teardown

Reverse-engineer a company's sales and marketing tech stack from public signals. Detects CRMs, cold email tools, people databases, ad pixels, email delivery services, and outbound sending domains via DNS records, website source inspection, Apify technology profiling, blacklist checks, and public spam complaint searches. Works on single companies or batches. Outputs a structured markdown report per company.

Gooseby Athina AI
Run in Gooseworks
Install
Terminal
npx gooseworks install --claude

# Then in your agent:
/gooseworks <prompt> --skill tech-stack-teardown
About This Skill

Tech Stack Recon

Reverse-engineer a company's sales, marketing, and outbound infrastructure from public signals. No login, no API access to their tools needed — everything is derived from DNS records, website source code, technology profiling, blacklist databases, and public complaints.

What It Detects

CategoryTools Detected
CRMHubSpot, Salesforce (via SPF, website pixels, DNS)
Cold Email ToolsSmartlead, Instantly, Outreach, Salesloft, Lemlist (via SPF, DKIM, TXT records, website source)
People DatabasesApollo, ZoomInfo, Clearbit, 6sense (via website tracker scripts)
Email DeliverySendGrid, Amazon SES, Postmark, Mailgun, Mandrill (via SPF includes, DKIM selectors)
Email MarketingMailchimp, Brevo, ActiveCampaign, Klaviyo (via DKIM selectors)
Ad RetargetingLinkedIn Insight Tag, Facebook Pixel, AdRoll, Reddit Ads, Twitter Ads (via Apify profiler + source)
Website BuilderWebflow, Framer, Next.js, WordPress (via Apify profiler + source)
Chat / SupportIntercom, Drift, Crisp, Zendesk (via website source)
AnalyticsGoogle Analytics, Segment, Mixpanel, Amplitude, PostHog, Heap (via website source)
Outbound DomainsSeparate cold sending domains (via SPF-only Google Workspace + redirect to primary)

How It Works

The skill runs 5 layers of detection, each revealing different signals:

Layer 1: DNS Records (Free, instant)

MX     → Primary email provider (Google Workspace, Microsoft 365, etc.)
SPF    → Every service authorized to send email on their behalf
DKIM   → Cryptographic proof of which tools actually send email
DMARC  → Email authentication policy (how strict they are)
TXT    → Misc verifications (Smartlead tracking domains, tool verifications)
CNAME  → Subdomains pointing to third-party services

This is the highest-signal layer. SPF and DKIM don't lie — if SendGrid is in their SPF, they use SendGrid.

Layer 2: Website Source Inspection (Free, instant)

Fetches the target website and searches HTML for:

  • Tracking pixels (Apollo, REB2B, HubSpot, Facebook, LinkedIn)
  • Script tags loading third-party tools
  • Meta tags and framework signatures
  • Hidden form handlers and API endpoints

Layer 3: Apify Technology Profiler (Pay-per-use, ~$0.005/domain)

Runs justa/technology-profiling-engine actor for deep detection of 7,000+ technologies using 8-tier inspection with confidence scores. Catches tools that don't appear in source code (loaded dynamically, via GTM, etc.).

Layer 4: Blacklist Checks (Free, instant)

Queries 6 major DNS-based blacklists:

  • Spamhaus (zen.spamhaus.org)
  • Barracuda (b.barracudacentral.org)
  • SpamCop (bl.spamcop.net)
  • SORBS (dnsbl.sorbs.net)
  • SURBL (multi.surbl.org)
  • URIBL (black.uribl.com)

Layer 5: Public Complaint Search (Free)

Web searches for spam complaints on Trustpilot, Reddit, SpamCop forums, and general web. Also searches for the company + tool names to find public mentions of their stack.

Cost

ComponentCost
DNS queriesFree
Website source fetchFree
Blacklist checksFree
Web searchesFree
Apify Technology Profiler~$0.005 per domain

Typical costs:

ScenarioDomainsEst. Cost
Single company1~$0.005
Small batch5~$0.025
Large batch20~$0.10

Skip the Apify profiler with --no-apify for free-only analysis (DNS + source + blacklists).

Setup

1. Required

# dig (DNS lookups) — included on macOS/Linux
which dig
 
# curl (website source fetch) — included on macOS/Linux
which curl
 
# Python 3 with requests + dotenv
pip3 install requests python-dotenv

2. Optional (for Apify Technology Profiler)

# Get your token at https://console.apify.com/account/integrations
# Add to .env:
APIFY_API_TOKEN=apify_api_YOUR_TOKEN_HERE

Usage

Single Company

python3 scripts/recon.py --domains pump.co

Batch of Companies

python3 scripts/recon.py --domains "dili.ai,pump.co,runautomat.com"

Free-Only Mode (No Apify)

python3 scripts/recon.py --domains pump.co --no-apify

Output to File

python3 scripts/recon.py --domains "dili.ai,pump.co" --output /path/to/report.md

JSON Output

python3 scripts/recon.py --domains pump.co --json

What the Script Does

For each domain:

  1. DNS Scan — Queries MX, SPF, DKIM (18 common selectors), DMARC, TXT records, and 30+ common subdomains (email, tracking, click, bounce, send, smtp, mail, etc.)
  2. Website Source Scan — Fetches the homepage HTML and greps for 40+ known tool signatures (script URLs, pixel IDs, tracking domains)
  3. Apify Technology Profile (optional) — Runs deep 8-tier technology detection for 7,000+ technologies with confidence scores
  4. Blacklist Check — Queries 6 DNS-based blacklists for the domain
  5. Outbound Domain Detection — Checks if common variations of the domain exist (get[name].com, try[name].com, [name]reach.com, etc.) and analyzes their DNS for cold outbound patterns
  6. Report Generation — Produces a structured markdown report with confirmed tools, evidence, email auth assessment, blacklist status, and an overall assessment

Agent Integration

When using this skill as an agent, follow this flow:

  1. User provides one or more company domains
  2. Run recon.py for all domains (confirm Apify cost if > 5 domains)
  3. Present the report — group findings by:
    • Confirmed tools (with evidence)
    • Email authentication (SPF/DKIM/DMARC assessment)
    • Deliverability (blacklist status + spam complaints)
    • Notable signals (outbound domains, missing DMARC, SPF gaps)
  4. If batch, include a comparative summary table at the end

Agent Without the Script

The agent can perform all checks manually using built-in tools:

DNS checks — Use Bash tool:

dig +short MX example.com
dig +short TXT example.com
dig +short TXT _dmarc.example.com
dig +short TXT selector._domainkey.example.com
dig +short CNAME subdomain.example.com

Website source scan — Use Bash tool:

curl -sL https://www.example.com | grep -oi 'pattern1\|pattern2\|pattern3' | sort -u

Blacklist checks — Use Bash tool:

dig +short example.com.zen.spamhaus.org A

Apify profiler — Use Bash tool with Python:

# See scripts/recon.py for the full implementation

Spam complaints — Use WebSearch tool:

"example.com" spam OR unsolicited OR "cold email" OR blacklist

DNS Record Cheat Sheet

SPF Includes → Tool Identification

SPF IncludeTool
_spf.google.comGoogle Workspace
spf.protection.outlook.comMicrosoft 365
sendgrid.netSendGrid
amazonses.comAmazon SES
*.hubspotemail.netHubSpot
*.rsgsv.net or servers.mcsv.netMailchimp/Mandrill
spf.mandrillapp.comMandrill (Mailchimp transactional)
mail.zendesk.comZendesk
*.freshdesk.comFreshdesk
spf.mailjet.comMailjet
spf.brevo.comBrevo (Sendinblue)
_spf.salesforce.comSalesforce
mktomail.comMarketo
postmarkapp.comPostmark
mailgun.orgMailgun

DKIM Selectors → Tool Identification

Selector PatternTool
google._domainkeyGoogle Workspace
selector1._domainkey / selector2._domainkeyMicrosoft 365
s1._domainkey / s2._domainkey*.sendgrid.netSendGrid
k1._domainkey*.mcsv.net or dkim.mcsv.netMailchimp
k2._domainkey / k3._domainkeydkim2.mcsv.net / dkim3.mcsv.netMailchimp
mandrill._domainkeyMandrill
pm._domainkeyPostmark
smtp._domainkeyGeneric SMTP
em._domainkeyVarious (check CNAME target)

TXT Records → Tool Identification

TXT PatternTool
open.sleadtrack.comSmartlead (custom tracking domain)
hubspot-developer-verification=*HubSpot
anthropic-domain-verification-*Anthropic (Claude)
MS=*Microsoft 365
google-site-verification=*Google Search Console
slack-domain-verification=*Slack
atlassian-domain-verification=*Atlassian (Jira/Confluence)
docusign=*DocuSign
facebook-domain-verification=*Facebook/Meta
_github-pages-challenge-*GitHub Pages
stripe-verification=*Stripe

Website Source Patterns → Tool Identification

Pattern in HTMLTool
assets.apollo.io/micro/website-trackerApollo.io (visitor tracking)
hs-script or js.hs-scripts.comHubSpot
px.ads.linkedin.comLinkedIn Insight Tag
connect.facebook.net or fbq(Facebook Pixel
snap.licdn.comLinkedIn Insight Tag
cdn.segment.comSegment
cdn.mxpnl.com or mixpanelMixpanel
cdn.amplitude.comAmplitude
app.posthog.com or posthogPostHog
widget.intercom.ioIntercom
js.driftt.comDrift
client.crisp.chatCrisp
static.zdassets.comZendesk
s3-us-west-2.amazonaws.com + reb2bREB2B
clearbit.com/tag.js or revealClearbit Reveal
6sc.co or 6sense6sense
tag.demandbase.comDemandbase
d.adroll.comAdRoll
googletagmanager.comGoogle Tag Manager
gtag('config', 'G-*')Google Analytics 4

Cold Outbound Domain Patterns

A separate domain is being used for cold email if it has:

  • Google Workspace MX (or similar) but no product/marketing email tools in SPF
  • SPF that only includes _spf.google.com (sending from raw mailboxes)
  • A 301/302 redirect to the company's primary domain
  • No website content of its own
  • Domain name follows patterns like: [brand]reach.com, get[brand].com, try[brand].com, meet[brand].com, [brand]hq.com

DMARC Assessment Guide

PolicyMeaningAssessment
p=rejectReject unauthenticated emailStrong — best practice
p=quarantineSend to spam if unauthenticatedGood — enforcing
p=noneMonitor only, don't enforceWeak — anyone can spoof the domain
No DMARC recordNo policy at allMissing — wide open to spoofing

Troubleshooting

"No tools detected"

  • The company may be very early-stage with minimal tooling
  • Some tools (like Apollo used only for prospecting, not sending) leave no DNS trace
  • LinkedIn Sales Navigator, Clay enrichment, and similar tools don't leave public signals
  • Try the Apify profiler if you only ran free-only mode

"SPF has Google only but they use Smartlead/Instantly"

  • This is normal. Smartlead and Instantly typically connect to Google Workspace mailboxes via SMTP and send through Google — so SPF passes via Google's include. The cold email tool itself doesn't need its own SPF entry.
  • Look for Smartlead's open.sleadtrack.com in TXT records or website source as confirmation.

"Apify profiler timed out"

  • Some sites take longer to load. The profiler has a 3-minute timeout.
  • Retry once. If it fails again, rely on DNS + source code analysis.

"artisan.ai resolves but redirects to Afternic"

  • The domain is parked/for sale. Check common alternatives: .co, .com, .io.
  • Wildcard DNS (all subdomains resolve to the same IP) is a sign of a parked domain.

Links

What's included

·
Tracking pixels (Apollo, REB2B, HubSpot, Facebook, LinkedIn)
·
Script tags loading third-party tools
·
Meta tags and framework signatures
·
Hidden form handlers and API endpoints
·
Spamhaus (zen.spamhaus.org)

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