Linux & Server Operations
Make a Bash script find its own files from any directory
Stop confusing the caller’s working directory with the script’s location; handle spaces, sourced files, relative symlinks and physical paths deliberately.
Read note →FIELD NOTES
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164published notes
Containers & Kubernetes
Copy files into a Docker container without losing control
Use docker cp with exact paths, verify ownership and destination semantics, and know when an image rebuild or mounted configuration is safer.
Read note →Product Engineering
Capture architecture decisions briefly
Before touching configuration, we will turn the symptom into a precise question and collect a baseline that can be compared after the work.Our specific objective is capture architecture decisions briefly. A …
Read note →Tech News
GitHub adds a Copilot usage metrics impact dashboard
Published 2026-07-22. This is a sourced Emmanuel Corels field briefing, written for builders who need the operational meaning behind the headline.What was actually announcedGitHub announced a Copilot usage m…
Read note →Cloud & DevOps
Tag cloud resources for accountability
Treat this task as a short investigation rather than a magic command. The command matters, but the context around it is what makes the result trustworthy.Our specific objective is tag cloud resources for acc…
Read note →Networking & ISP Systems
Audit active DNS resolvers
Treat this task as a short investigation rather than a magic command. The command matters, but the context around it is what makes the result trustworthy.Our specific objective is audit active dns resolvers.…
Read note →Automation & Scripting
Stream a large Python data job with yield instead of filling memory
Turn an all-at-once import into a lazy, testable pipeline while preserving cleanup, error context, batching and backpressure.
Read note →Databases & Reliability
Read PostgreSQL index usage
This is a practical operator’s guide: establish context, run the smallest useful check, interpret it correctly, and leave a clean recovery path.Our specific objective is read postgresql index usage. Use work…
Read note →Cybersecurity
Find failed SSH authentication patterns
This is a practical operator’s guide: establish context, run the smallest useful check, interpret it correctly, and leave a clean recovery path.Our specific objective is find failed ssh authentication patter…
Read note →Web Infrastructure
Debug PHP foreach mutations and lingering references
Reason about PHP 8 array iteration, copy-on-write, in-loop mutation, and the reference that survives after foreach.
Read note →Linux & Server Operations
Schedule reliable work with systemd timers
When this problem appears in production, urgency encourages guessing. The procedure below deliberately slows the first minute down so the next thirty are useful.Our specific objective is schedule reliable wo…
Read note →Containers & Kubernetes
Clean Docker space deliberately
There are several ways to get a plausible answer here. This guide focuses on the path that preserves evidence and minimizes accidental change.Our specific objective is clean docker space deliberately. Measur…
Read note →Page 6 of 14 · 164 posts