Vigilmon vs AppSignal: Uptime Monitoring vs Application Performance Monitoring (2026)

Vigilmon and AppSignal both monitor your applications — but from completely different angles. Choosing the wrong tool means either missing uptime incidents or overpaying for features you don't use.

This comparison breaks down exactly what each tool does and when you need one, the other, or both.

What Is AppSignal?

AppSignal is an application performance monitoring (APM) and error tracking tool, originally built for Ruby on Rails and Elixir but now supporting Node.js, Python, and more.

It instruments your application from inside — wrapping your code to track:

• N+1 database queries
• Slow background jobs
• Exception/error tracking with stack traces
• Performance per endpoint
• Memory and CPU usage
• Host metrics

What Is Vigilmon?

Vigilmon is an external uptime monitoring service that pings your app from outside your infrastructure:

• HTTP/HTTPS status checks every 1 minute
• SSL certificate expiry monitoring (30/14/7 day warnings)
• Multi-region probes (confirms reachability from multiple locations)
• Status pages (for user-facing incident communication)
• Heartbeat monitoring (for cron jobs and scheduled tasks)

The Core Difference: Inside vs Outside

AppSignal view:          Vigilmon view:
   [Your App]              [Internet]
   [Code traces]           [HTTP request]
   [DB queries]            [DNS lookup]
   [Memory usage]          [TLS handshake]
   [Error stacks]          [Response code]

AppSignal knows why your app is slow. Vigilmon knows if your app is reachable at all.

What AppSignal Catches That Vigilmon Doesn't

• N+1 queries causing 2-second page loads
• A single slow endpoint degrading user experience
• Memory leak gradually growing over hours
• Unhandled exceptions in specific code paths
• Background job failures with stack traces
• Performance regression after a deploy

What Vigilmon Catches That AppSignal Doesn't

• Total process crash (no requests = no APM data)
• DNS failure (app is running but unreachable)
• Network partition between user and server
• SSL certificate expired
• Cloud provider outage (entire region down)
• Load balancer misconfiguration
• Deployment that broke startup

When your process crashes, AppSignal goes silent — it can't report from a dead process. Vigilmon's external probes continue and alert you.

Pricing Comparison

	Vigilmon	AppSignal
Free tier	✅ 5 monitors	✅ Limited trial
Starting price	~$10/month	~$18/month
Pricing model	Flat/monitors	Per-host or per-user
Per-host cost	None	$18+/host/month
Ruby support	External HTTP check	Deep instrumentation
Multi-language	Any HTTP service	Ruby, Elixir, Node, Python

For a typical 3-host Rails app, AppSignal runs ~$54+/month. Vigilmon covers all 3 hosts externally at a fraction of that.

Use Case Decision Tree

Use Vigilmon when:

• You need to know if your site is up right now
• You want to catch infrastructure failures before users call you
• You're monitoring SSL expiry
• You're running cron jobs that need heartbeat verification
• You want a status page for users
• You're cost-conscious and don't need code-level APM

Use AppSignal when:

• You need to debug slow Rails controllers
• You're tracking exception rates and stack traces
• You want N+1 query detection
• You're doing performance profiling on specific code paths
• You have a Ruby/Elixir/Node app and want language-native metrics

Use both when:

• You're running a production app with SLA requirements
• You need both "is it up?" (Vigilmon) and "why is it slow?" (AppSignal)

Integration Story

Vigilmon and AppSignal complement each other well:

# app/controllers/health_controller.rb
class HealthController < ApplicationController
  # Vigilmon pings this from outside every minute
  # AppSignal instruments this like any other action
  def show
    checks = {
      database: ActiveRecord::Base.connection.execute("SELECT 1").any?,
      redis: $redis.ping == "PONG"
    }
    status = checks.values.all? ? :ok : :service_unavailable
    render json: { status: status, checks: checks }, status: status
  end
end

When this endpoint returns 503:

• Vigilmon fires an alert within 60 seconds to your on-call channel
• AppSignal shows you the error trace explaining why the check failed

AppSignal's Uptime Monitoring (Yes, It Has One)

AppSignal includes basic uptime monitoring — but it's not the focus. Limitations:

• Check intervals are longer (typically 5 minutes vs Vigilmon's 1 minute)
• No multi-region probes
• No dedicated SSL monitoring
• No status page builder

For teams already on AppSignal, their built-in uptime check may be sufficient for simple use cases. But for production apps where every minute of downtime matters, Vigilmon's 1-minute interval and multi-region approach is worth having alongside it.

Verdict

Team Profile	Recommendation
Solo dev / side project	Vigilmon free tier only
Rails app, no APM budget	Vigilmon paid
Rails app, need error tracking	AppSignal alone (includes basic uptime)
Production app with SLA	Vigilmon + AppSignal
Cost-sensitive production	Vigilmon + Sentry free (error tracking)

For most teams: start with Vigilmon for external monitoring. Add AppSignal when you need to debug why things are slow, not just when they're down.

---

Start external monitoring free at vigilmon.online — 5 monitors, no credit card.