Engineering Blog
The UpMonitor engineering blog covers the technical craft of keeping production sites alive — SSL renewals, DNS propagation, security-header audits, performance tuning, and the AI-native incident workflows that turn 60-minute MTTR into 10-minute MTTR.
How the upmonitor:// Protocol Turns AI Agents into Self-Healing Infrastructure
Learn how the UpMonitor CLI and custom protocol bridge the gap between cloud alerts and local recovery playbooks for AI agents.
What Is DNSSEC? The Chain of Trust Explained
DNSSEC signs DNS records so a resolver can prove an answer is genuine. See the 6 record types, the chain of trust from root to zone, and how to fix SERVFAIL.
What Is TTFB? Time to First Byte Explained and Measured
TTFB is the time from the start of a request to the first byte of the response. See the 5 phases inside it, the 800 ms good threshold and 6 ways to cut it.
AI Agents Ship Fast, Security Slips Through (2026)
AI coding agents optimize for code that runs, not behavior that is correct. Green CI and HTTP 200 hide silent regressions. Here is how to catch them.
Googlebot's 2MB Crawl Limit: Why Your Decompressed HTML Goes Uncrawlable (and How to Fix It)
Googlebot indexes only the first 2MB of your HTML, measured on uncompressed bytes, distinct from the 15MB fetch limit. Detect silent truncation and fix it.
HSTS Preloading Guide: How to Secure Your Domain at the Browser Level
Learn how to get your domain on the global HSTS preload list to ensure maximum transport security.
HTTP Status Codes Explained: The 5 Classes and 24 Codes
HTTP status codes explained: the 5 response classes, the 24 codes that carry a decision, and the fix for the 6 failures that break sites and crawling.
How to Fix Mixed Content Warnings on an HTTPS Site
Fix mixed content in 3 steps: find every http:// resource with DevTools and a report-only CSP, rewrite the source, then add upgrade-insecure-requests.
DNS Propagation Guide: How Long It Takes and How to Check It
DNS propagation ends when the last cached copy of the old record expires. See how TTL, negative caching and TLD delegation set the wait, and how to check it.
Technical SEO Audit Guide: Robots.txt, Sitemaps, and Meta Tags
How to ensure your website is fully discoverable by search engines and AI crawlers using our free diagnostic tools.
Free Website Uptime Monitoring: How to Get Started in 2026
A beginner's guide to setting up professional-grade uptime monitoring and diagnostic audits for free.
Security Headers Guide: HSTS, CSP, and X-Frame-Options Explained
How to implement and verify critical HTTP security headers to protect your website from client-side attacks.
SSL Certificate Errors: Decode & Fix NET::ERR_CERT_* and More
Every common SSL/TLS browser error decoded - NET::ERR_CERT_DATE_INVALID, ERR_CERT_AUTHORITY_INVALID, handshake failures, name mismatch - with the exact openssl probe and server-config fix for each.
How to Build a Website Monitoring Pipeline in CI/CD
Build a website monitoring pipeline in CI/CD: 5 stages, the UpMonitor CLI gate with --fail-on, GitHub Actions and GitLab CI jobs, and the 5 default checks.
How to Ensure Your Website Is Secure: 8-Point Checklist
Secure a website with 8 outside-in checks: a 1-hop HTTPS redirect, a valid certificate chain, TLS 1.2+, HSTS and 6 more headers, DNSSEC, no version leaks.
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