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ツールと組み合わせた開発者向けの詳細記事。
- 2026年8月18日
Android performance via ADB: how to read CPU, GPU, and NPU utilization
Read CPU, GPU, and NPU usage from any Android device over ADB — dumpsys cpuinfo and /proc/stat for CPU, Adreno kgsl and Mali devfreq sysfs nodes for GPU, and honest guidance on why NPU utilization has no standard interface.
記事を読む → - 2026年8月18日
Windows cleanup guide: reclaim disk space on every version from 7 to 11
Safe, version-specific ways to free disk space on Windows 11, 10, 8 and 7 — Storage Sense, Disk Cleanup, DISM component cleanup, developer caches, and what never to delete.
記事を読む → - 2026年8月18日
How to check CPU, RAM, and disk model and capacity on Windows — GUI and command line
Every way to see your hardware specs on Windows: Task Manager and msinfo32 for quick checks, wmic and PowerShell CIM for exact CPU model, per-stick RAM capacity and part numbers, disk model and health — plus why wmic is deprecated on Windows 11.
記事を読む → - 2026年8月18日
How to install an SSH server on Windows: built-in OpenSSH for 11/10, manual setup for 8.1 and 7
Step-by-step OpenSSH server setup for every Windows version — the built-in optional feature on 11/10, Win32-OpenSSH for older systems, key-based auth with the administrators_authorized_keys gotcha, and hardening.
記事を読む → - 2026年8月17日
HMAC, explained: how keyed hashing protects webhooks
What HMAC actually computes, why plain SHA-256 is not enough, and how to verify webhook signatures like the ones Stripe and GitHub send.
記事を読む → - 2026年8月9日
API request signing: the complete nonce + timestamp + HMAC workflow
How to sign API requests with HMAC, why the timestamp and nonce are what actually stop replay attacks, and a full curl-to-code example you can verify in your browser.
記事を読む → - 2026年8月9日
bcrypt vs SHA-256: choosing the right hash for password storage
Why fast hashes like MD5 and SHA-256 are the wrong tool for storing login passwords, how bcrypt's cost factor and built-in salt fix that, and how to pick a cost you can defend.
記事を読む → - 2026年8月9日
CIDR and subnetting, explained: prefixes, netmasks and VLSM
How a.b.c.d/n really works — converting between prefix length and netmask, finding network and broadcast addresses by hand, and carving one /24 into right-sized subnets with VLSM.
記事を読む → - 2026年8月9日
HMAC and API request signing: a practical walkthrough with real numbers
How to sign API requests with HMAC — canonical request strings, timestamp and nonce anti-replay, webhook verification, and how it compares to JWT. With reproducible digests you can check in your browser.
記事を読む → - 2026年8月9日
JSON formatting and validation in practice: pinpoint the error, not the vibes
Why formatted JSON is easier to debug, the five syntax errors you will actually meet, and how row-and-column error location turns a frustrating afternoon into a two-minute fix.
記事を読む → - 2026年8月9日
Regular expressions in practice: patterns, capture groups, and the backtracking trap
A working developer's guide to regex: the patterns you actually need, how capture groups and references behave, why catastrophic backtracking freezes tabs, and how to test patterns before they hit production.
記事を読む → - 2026年8月9日
Unix timestamps and time zones: a complete guide for developers
What a Unix timestamp really counts, why UTC is not a time zone, how ISO 8601 works, and where DST breaks naive code — with real conversions you can verify in the browser.
記事を読む → - 2026年8月9日
URL encoding, explained: percent-encoding, reserved characters, and component vs full URLs
Why URLs need percent-encoding at all, which characters RFC 3986 reserves, when to encode a component versus a whole URL, and how base64url fits in — with worked examples you can verify in the browser.
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