The CodeKits notebook
Ideas into working code.
Practical tutorials, project walkthroughs and development notes. Explore the code, understand the structure, and build something of your own.
8 articles · Newest first
Ubuntu
Deploy a frontend, backend and database together
Connect a frontend, API and MySQL through an explicit deployment contract, private credentials, readiness checks and compatible migrations.
· 4 min read
Ubuntu
Diagnose Nginx 502 errors after deployment
Trace a 502 from Nginx to the listening port, systemd process and application logs, then distinguish refusal, timeout and upstream errors.
· 4 min read
Ubuntu
Find Linux ports, processes and systemd services
Trace a Linux listening port to its process and systemd unit, distinguish bindings and connections, and avoid killing the wrong service.
· 4 min read
Ubuntu
Monitor HTTPS certificate expiry and renewal
Check the certificate visitors actually receive, test Certbot renewal separately, and rehearse an expiry alert without breaking HTTPS.
· 4 min read
Ubuntu
Route several apps through one Nginx domain
Route a website, API and WebSocket through one Nginx hostname with explicit prefix handling, forwarding headers and predictable tests.
· 4 min read
Ubuntu
Create server-health alerts with systemd timers
Build a bounded server-health check with deduplicated email alerts, recovery notices and a systemd timer, then test without harming services.
· 4 min read
Ubuntu
Set up an Ubuntu VPS without locking yourself out
Prepare an Ubuntu VPS with a sudo user, tested SSH keys, updates and UFW rules while keeping a working recovery path throughout.
· 4 min read
Ubuntu
Run a website, Node API and MySQL on one VPS
Plan a small single-VPS stack with clear service boundaries, memory and connection budgets, durable storage and a realistic recovery plan.
· 4 min read