Domains
Domains, DNS and email: connecting a custom domain, the records that matter, redirects and propagation, and sending mail that lands in the inbox.
19 posts
"Your Connection Is Not Private" on Your Own Site: Causes and Fixes
When visitors see NET::ERR_CERT_DATE_INVALID, ERR_CERT_COMMON_NAME_INVALID or ERR_CERT_AUTHORITY_INVALID on your site, the SSL certificate is expired, for the wrong name, or incomplete. How to tell which, and how to fix each one.
What Is Cloudflare? What It Does When You Put Your Site Behind It
Cloudflare sits between your visitors and your server: DNS, a CDN, free SSL, DDoS protection and a firewall. What changes when you turn on the orange cloud, what it costs, what it can break, and whether a small app needs it.
Cloudflare Proxied vs DNS Only: The Orange Cloud Explained
In Cloudflare's DNS settings, the orange cloud sends traffic through Cloudflare and the grey cloud doesn't. What changes with each, which records must be grey, the SSL modes that avoid redirect loops, and how proxying interacts with your host's automatic SSL.
.com vs .io vs .ai vs .app: How to Choose a Domain Extension
The ending of your domain affects trust, price and renewal cost more than SEO. What .com, .io, .ai, .app, .dev and country codes signal, which ones force HTTPS, why renewal prices matter more than first-year prices, and a quick way to decide.
www vs non-www: Which Should Your Website Use?
example.com or www.example.com? What the difference actually is, why it doesn't matter for SEO as long as you pick one, how to redirect the other, the DNS catch with root domains, and the cookie consideration that makes some teams choose www.
How to Transfer a Domain to Another Registrar (Without Breaking Your Site or Email)
A step-by-step domain transfer guide: what moves and what doesn't, the transfer lock and auth code, how long it takes, copying DNS records first so your site and email keep working, and the difference between transferring a domain and just changing nameservers.
Subdomain vs Subdirectory: blog.example.com or example.com/blog?
Should your blog, docs or app live on a subdomain (app.example.com) or a subdirectory (example.com/app)? The technical differences, what it means for SEO, cookies and hosting, and sensible defaults for a small product.
Mixed Content Errors: Why Your HTTPS Site Loads Things Over HTTP (and How to Fix It)
"Mixed Content: The page was loaded over HTTPS, but requested an insecure resource." What mixed content is, why browsers block it, how to find every http:// URL, and the fixes — including apps behind a proxy that generate http links.
How to Get Your Website on Google: A Beginner's Step-by-Step Guide
Your new site doesn't show up on Google. How to check whether it's indexed, set up Google Search Console, verify your domain, submit a sitemap, request indexing, fix the common blockers, and what to realistically expect in the first weeks.
ERR_TOO_MANY_REDIRECTS: What Causes It and How to Fix It (Including Cloudflare)
"This page isn't working — redirected you too many times." The usual causes of a redirect loop — Cloudflare's Flexible SSL mode, conflicting www rules, an app that doesn't know it's behind a proxy, and login loops — and how to find and fix each.
DNS Propagation Explained: Why Domain Changes Take Time (and How to Speed Them Up)
You changed a DNS record and your site still points to the old place. What "DNS propagation" really is (caching, not spreading), how TTL controls the wait, why nameserver changes take longest, how to check from different places, and how to flush your own cache.
What Is HTTPS? The Padlock, Explained for Beginners
HTTPS is why the browser shows a padlock instead of 'Not secure'. What it protects, what it doesn't, what a certificate is, why your app needs it before launch, and how to fix the common 'mixed content' and certificate errors.
What Is a Domain Name? (And How to Buy One Without Getting Caught Out)
A domain name is your app's address on the internet — and the one part of it you should truly own. What domains are, how to pick one, where to buy it, and the renewal-price and ownership traps that catch first-time buyers.
How to Send Email From Your App Without Landing in Spam
Password resets, receipts, and sign-up confirmations that land in spam — or never arrive — are one of the most common launch-week problems. What SPF, DKIM, and DMARC actually do, how to set them up for your domain, and why your app should never send mail itself.
How Automatic SSL Actually Works (and Why It Sometimes Doesn't)
The padlock in the browser comes from a certificate that has to be issued, installed, and renewed on a schedule that keeps getting shorter. How Let's Encrypt and ACME prove you own a domain, how tools like Traefik and Caddy automate it, and the five reasons a certificate fails to issue or renew.
DNS Records Explained: A, CNAME, MX, and TXT for Beginners
Your domain's DNS settings page is a table of cryptic records. What A, AAAA, CNAME, MX, TXT, and NS records do, how subdomains work, what TTL means, why changes 'take time to propagate', and how to check what the world actually sees.
How to Get a Custom Email Address for Your Domain
you@yourapp.com looks far more trustworthy than yourapp.support@gmail.com. The options — Google Workspace, Microsoft 365, Zoho, Proton, Fastmail, and forwarding — how MX, SPF, DKIM, and DMARC records set it up, and how mailboxes differ from sending email from your app.
How to Connect a Custom Domain to Your App: DNS Without the Jargon
Your app works at a long platform URL, and you want it at yourname.com. What DNS records actually do, A vs CNAME in plain English, the apex-domain problem, how HTTPS gets issued, and how to fix the usual errors.
Anatomy of a URL: What Every Part of a Web Address Means
https://app.example.com:8080/orders/42?sort=new#details has seven parts, and each one matters when you build an app. The scheme, subdomain, domain, port, path, query string, and fragment, explained — plus URL encoding and why some characters turn into %20.