Competitor Monitor – Tech Stack, DNS & Key Page Changes

Give it a competitor's domain and, on every scheduled run after the first, it tells you what changed: technologies added or removed, a new or dropped email/DNS provider (MX hosts, nameservers, authorized SPF senders, and domain-verification TXT tokens — usually a new SaaS sign-up), and text changes on the competitor's own pricing and careers pages, found automatically from its homepage. The first run for a domain takes the baseline; every run after that is a comparison. Only the competitor's own pages are compared — never a third-party job board or review site. Put it on an Apify schedule and it becomes a monitor. You pay per check that gave an answer.

What you get

One dataset item per processed distinct domain; timeouts and charge caps can leave inputs unfinished. Here is one, for a scheduled recheck of a competitor that switched email providers, swapped one marketing tool for another and raised its price:

{
  "domain": "acme.com",
  "monitorName": "daily",
  "reasonCode": "changed",
  "technologies": {
    "current": [{ "name": "Intercom", "category": "chat", "source": "html", "evidence": "widget.intercom.io" }],
    "added": [{ "name": "Intercom", "category": "chat", "source": "html", "evidence": "widget.intercom.io" }],
    "removed": [{ "name": "Drift", "category": "chat", "source": "html", "evidence": "js.driftt.com" }]
  },
  "mx": { "current": ["aspmx.l.google.com"], "added": ["aspmx.l.google.com"], "removed": ["mail.oldprovider.com"] },
  "ns": { "current": ["ns1.acme.com"], "added": [], "removed": [] },
  "spfIncludes": { "current": ["_spf.google.com"], "added": ["_spf.google.com"], "removed": ["oldprovider.net"] },
  "verificationTxt": { "current": ["google-site-verification=abc"], "added": ["google-site-verification=abc"], "removed": [] },
  "pricingPage": { "url": "https://acme.com/pricing", "added": ["$15 per month"], "removed": ["$10 per month"] },
  "careersPage": { "url": null, "added": [], "removed": [] },
  "previousCheckedAt": "2026-09-26T06:00:04.118Z",
  "checkedAt": "2026-09-27T06:00:03.902Z"
}

The first run for a domain stores its baseline and reports reasonCode: "baseline". Every later run that can compare against it reports unchanged, changed, or domain_gone if the competitor's site vanished entirely. A bot wall or an unreachable site on any run — first or later — is free instead and leaves the stored baseline untouched, so the next run that does succeed still compares against the last one that did.

Run it on a schedule

One run is a snapshot. A schedule is what makes it a monitor.

1. Fill in domains and save the input as a task.
2. In Apify Console open Schedules, click Create new, add the task and set the cron expression to @weekly (or @daily).
3. The first scheduled run takes the baselines and reports baseline. Every run after that reports what changed.

To hear only about what matters, read the run's dataset and keep the rows where reasonCode is changed or domain_gone. Apify's Slack integration posts when a run finishes but cannot see the rows, so on its own it tells you the check ran, not what it found. A Make, n8n or Zapier workflow that starts when the run finishes, fetches the dataset items and filters on that field does.

What it costs at $0.003 per check: 50 competitors weekly is about $0.65 a month, 50 competitors daily about $4.50.

Use it when

• You track a shortlist of competitors and want a weekly (or daily) diff instead of re-reading their sites by hand.
• A competitor's tech stack or email provider change tells you something (a new CRM, a new ESP, a payment processor swap).
• A new domain-verification TXT record (google-site-verification=, atlassian-domain-verification=, ...) usually means the competitor just signed up for a SaaS tool, before it shows up anywhere else.
• You want to know the moment a competitor's pricing page or careers page changes — a price move, a new plan, a hiring spree or a hiring freeze.
• An agent needs "what changed about this competitor since last week" as structured data, not a screenshot.

Input

Field	Type	Required	What it does
domains	array of strings	yes	Up to 1,000 competitor domains or URLs per run. A repeated site is checked and charged once.
monitorName	string	no	Keeps this monitor's snapshots apart from any other monitor watching the same domains. Use one per scheduled task. Change it to start over from a fresh baseline. Lowercase letters, digits and hyphens, up to 40.

How it works

Each run reads the domain's DNS (MX, nameservers, TXT) and crawls its homepage plus, when linked from there, its pricing and careers pages. A careers or pricing link that redirects off the competitor's site (to a hosted job board, say) is not compared. Technologies are fingerprinted from that HTML and DNS using the same ~80-entry table as the Tech Stack Detector Actor (CMS, ecommerce, framework, analytics, marketing, chat, payments, consent, CDN, email and business-app tools). The result is compared against the snapshot the previous run stored:

• technologies — every technology currently fingerprinted, plus which ones are new or gone since last time.
• mx / ns — the domain's current mail servers and nameservers, plus what changed. A new MX host is usually a mail-provider migration; a new nameserver is usually a DNS or hosting migration.
• spfIncludes — the include: hosts in the domain's SPF record: who is currently authorized to send mail as this domain, and who was added or dropped.
• verificationTxt — other TXT records shaped like a domain-ownership verification token (key=value, e.g. google-site-verification=...). A new one is usually a new SaaS vendor's onboarding step, even one the technology table doesn't recognize by name.
• pricingPage / careersPage — the pricing and careers/jobs page found from the homepage (by URL pattern, e.g. /pricing, /careers), with the lines of visible text added or removed since last time, the same text-diff approach as the Website Change Monitor Actor. url is null when the homepage links no such page. A linked page that can't be read on a run (an error, a redirect off-site, no text) reports no change rather than all its text removed, and a page the first run couldn't read is not reported as all-new the first time it can. Only the lines that moved are reported, never the whole page.

Snapshots are kept in a key-value store named competitor-monitor-4vvponclb65hiavis (the Actor's name and id) in your own Apify account, one per domain and monitorName. Deleting that store resets every baseline.

Pricing

Pay per event, $3.00 per 1,000 checks ($0.003 each) that gave an answer, charged on the competitor-monitor-checked event.

reasonCode	Charged
baseline (no earlier snapshot for this domain and monitorName: the baseline is taken)	yes
unchanged (compared against the previous snapshot; nothing moved)	yes
changed (compared; see technologies, mx, ns, spfIncludes, verificationTxt, pricingPage, careersPage)	yes
domain_gone (DNS says the domain no longer exists, and a baseline had it: a real finding for a monitored competitor)	yes
domain_not_found (DNS says the domain does not exist, and it was never checked before: most likely a wrong domain)	no
website_blocked (401, 403 or 429 on the homepage: a bot wall, not an answer)	no
website_unreachable (no DNS, no connection, a timeout, or a server error)	no
invalid_domain (an IP, a bare TLD, localhost, a malformed name)	no

A free check never overwrites the stored baseline, so the next check that can see the domain still compares against the last one that did. If DNS itself fails to answer on an otherwise-successful check, the MX/nameserver/SPF/verification-TXT fields and the DNS-sourced technologies are carried forward from the last snapshot rather than reported as gone — a resolver outage on our side is never read as a change on the competitor's. If DNS failed on the baseline run itself, those fields show current: null (unknown, not empty), and the first run that reads them records them without reporting them as added.

Technologies are compared by vendor, not by where the evidence came from: Stripe seen in the HTML today and only in a TXT record last time is the same Stripe, not a new one. A domain that comes back after domain_gone reports changed, with everything it came back with listed as added.

A charge cap stops new work. Up to seven other sites may already be in flight and can return uncharged rows. Inputs not started are omitted; join rows to inputs by domain and resubmit only missing sites.

Limits

• Pricing and careers pages are found among at most 3 same-site links from the homepage matching common path shapes (/pricing, /plans, /careers, /jobs, ...). A site that names them differently, links them from somewhere other than the homepage, or hides them behind a JavaScript-rendered menu, will show url: null.
• Pages are read as served, without running JavaScript. A page that renders its content client-side may show no page found, or no change where a human would see one.
• Text that differs on every load (an A/B-tested fragment, a personalized recommendation widget, a "posted 3 minutes ago" line) reports a change every run, the same limitation website-change-monitor's text diff has. A real run against stripe.com/pricing hit exactly this: a "not sure where to start?" recommendation block reordered between two checks a minute apart, with no real pricing change underneath it.
• Technologies come from a fixed table of markup and DNS patterns, not from running JavaScript or reading HTTP response headers. A technology missing from technologies.current means it wasn't seen — never that the competitor definitely doesn't run it.
• Up to eight domains run concurrently; rows arrive in finish order, not input order. Persisted rows survive a timeout.
• Each page is capped at 4 MiB and 15 seconds including DNS, redirects and retries. Every hop validates all DNS addresses and pins a public IP. Unsafe or unsupported redirects are refused; unreadable extra pages are skipped.
• This only compares the competitor's own pages and public DNS records — never a job board, a review site, or any other third party. A key page that redirects elsewhere is fetched once per run (that is how the redirect is seen) but never compared.

Data sources

The competitor's own site, fetched directly, and its public DNS records, read through Cloudflare's public DNS-over-HTTPS resolver (1.1.1.1). No paid or third-party data service. Snapshots stay in a key-value store in your own Apify account.