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Showing entries 441–480 of 651 in this first collection.
Troubleshooting guide
A secret was committed to git: revoke it first, then decide whether to rewrite history
Order the response to a committed credential correctly: revoke, remove it from the code, decide on a history rewrite and its limits, and stop the next one with ignore rules and push-time scanning.
Inspectable example
Example stabilisation ledger for five flaky tests, with how to read the run counts
An inspectable synthetic ledger of five tests showing baseline failures and rates, classified causes, fixes, a not-reproduced test and an approved open quarantine, with how the required run count is worked out and what a clean run count can and cannot show.
Inspectable example
Example definition of three critical flows for a browser smoke suite, with break checks
An inspectable synthetic definition of three flows with start, steps, observable end state, data, third-party handling and the deliberate fault that must make each test fail.
Inspectable example
Example rotation checklist for a committed access key, with what the account holder does
An inspectable synthetic checklist in the order a rotation should happen: revoke, replace, configure, verify, review logs, find copies and only then clean the repository.
Inspectable example
Example written review of one pull request: findings, labels and a not-examined list
An inspectable synthetic review of an invented pull request showing the five parts of a finding, the shown and suspected labels, and the list of what was not examined.
Troubleshooting guide
Error reports show minified code: make stack traces readable with source maps
Work out why an error tracker shows bundled, minified lines and check that the build, the upload and the deployed code agree, using a deliberate test error rather than waiting for a real one.
Troubleshooting guide
Check what your error reports contain before launch, and filter sensitive data at the source
Find out what an error event carries beyond a stack trace, choose where to scrub it, use a before-send hook and test the filter with invented secrets before real traffic arrives.
Troubleshooting guide
An error tracker that alerts on everything gets muted: tune grouping and alert rules
Understand how events are grouped into issues, why one fault becomes many issues, and how to build one alert rule that tells the right person about the right thing.
Troubleshooting guide
Follow one request through your logs: structured records and a request ID in Python
Turn free-text log lines into records a program can parse and attach a request identifier with filters and context variables so every line from one request can be found together.
Troubleshooting guide
One slow endpoint or page: measure the distribution before you change any code
Build a measurement two people would agree on, read percentiles instead of averages, separate lab from field figures and decide what a believable before and after comparison has to show.
Platform
Sentry: see production errors with readable traces, safe payloads and one alert you can trust
What an error tracker needs before it is useful: readable stack traces, release and environment, filtered sensitive data and a quiet alert, with the guide that covers each and the paid setup job.
Platform
pytest: fixtures, patching and markers, and where test suites quietly go wrong
How pytest's fixture scopes, monkeypatch, temporary directories and skip or xfail markers shape test reliability, with the guide for each pattern and the bounded jobs that fit.
Troubleshooting guide
What a useful written pull request review contains, and what it cannot tell you
Set the standard for a written review of a pull request: what to look at, how to write a finding someone can verify and why a review informs a merge decision without making it.
Troubleshooting guide
Your setup instructions have never been run on a clean machine: test the README before you hand it over
Find the hidden prerequisites in a README by following it, and only it, on a clean environment, and know who should try it and what to record.
Troubleshooting guide
Scanning one page is not an accessibility audit: how to scope an audit of a single flow
Separate what automated accessibility checks find from what needs a person, scope an audit by complete process rather than by page, and know which WCAG 2.2 criteria are new.
Troubleshooting guide
A pytest test passes alone but fails in the full run: look for shared state first
Find what one test leaves behind for the next one, from wide fixture scopes to shared files and environment changes, and prove the cause by changing the order instead of guessing.
Troubleshooting guide
A test fails only at certain times or on some machines: find the clock, the randomness or the environment
Trace a test that depends on the date, a random value or the machine it runs on, and control that input instead of waiting for the next failure.
Troubleshooting guide
Before you skip or mark a flaky test, know what the marker hides
Compare skip, xfail, strict xfail and a separate quarantine suite so that taking a flaky test out of the way leaves a visible, dated record instead of a permanent blind spot.
Free tool
Backlog cost and break-even calculator: arithmetic on your own backlog numbers
Enter your backlog by size, your own hours, review hours, hourly cost, lead time, pace and a monthly running cost to compare, and see total hours, total cost, months to clear and break-even. Not a quote.
Free tool
GitHub Actions failure triage: an ordered checklist of what to check first
Answer eight questions about a failing GitHub Actions run and get an ordered checklist from fixed, documented rules, with the reason, the evidence to collect and the limits of each step. It does not read your logs or diagnose the failure.
Free tool
CSV header diff: find missing, added, renamed and duplicate columns between two files
Paste two CSV header rows, or read the header of two small files in your browser, and see missing, added and likely renamed columns, duplicate and empty headers and the delimiter. Nothing is uploaded.
Free tool
Invoice rounding bench: compare per-line and total rounding, half-up and half-even
Enter invoice lines and see net, tax and gross under four rounding rules side by side, in exact whole-number minor units, with the difference between summing lines and rounding the total. Not tax or accounting advice.
Free tool
Certificate expiry countdown: sort your HTTPS certificates by time left
Paste hostnames and certificate not-after dates. See them sorted by time remaining, flagged at 7, 30 and 60 days, with a renewal-by date for each. Nothing is looked up.
Free tool
DNS cutover TTL planner: when to lower the TTL, switch and raise it again
Enter the current TTL, your planned switch time, the TTL to lower to and when you can lower it. Get exact timestamps and the worst-case time old answers can linger.
Free tool
SPF, DKIM and DMARC record checker: read your pasted records against the RFCs
Paste your SPF, DMARC and optional DKIM key records as text and get specific findings, each with the RFC section behind it. No DNS lookups; nothing leaves your browser.
Free tool
Pack and case unit-price calculator: compare supplier prices per single unit
Enter supplier price lines priced per unit, pack or case. Get the exact price per single unit, the working, and the lines whose pack basis is unclear. No floating point.
Buyer collection
For an engineering lead: turn 'we are behind on versions' into a ranked, dated plan
Name the forcing event, decide who accepts each step, and choose the smallest paid job that answers the question: a plan, one upgrade, a programme or a standing service.
Buyer collection
For an owner whose app nobody maintains: ask for a checkable result, not a version number
Turn a host's retirement notice into a plain request: which part is affected, what 'working' means, who can release it and what you need to send.
Collection
Which upgrade first? A diagnosis order for runtime, framework, build tool and database
An ordered map from the first warning to the right paid job: forcing date, test baseline, inventory, runtime, framework, front-end tooling, data and host, and keeping it supported.
Collection
Moving an app or database to another host or engine: the order that avoids lost writes
An ordered map from the dependency inventory to a rehearsed copy, reconciliation, a write freeze, the switch and a way back, for Heroku moves and MySQL to PostgreSQL moves.
Inspectable example
Synthetic upgrade register: one invented Node.js app, five components and a ranked path
An invented inventory shows how support dates, a test baseline and prerequisites turn into an ordered upgrade path, including a component whose date is unknown and one that is outside our fixed jobs.
Inspectable example
Synthetic MySQL to PostgreSQL reconciliation: counts, checksums, sequences and one failing lookup
An invented rehearsal result shows what per-table evidence looks like, including a zero-date column, a generated-key check and a case-sensitivity failure that must be decided, not hidden.
Inspectable example
Synthetic Express 4 to 5 URL table: patterns, async errors, dotfiles and a removed method
An invented before-and-after table shows how to check that converted route patterns still match the right URLs, with each expected Express 5 result taken from the migration guide.
Troubleshooting guide
MySQL to PostgreSQL: the decisions a data copy does not make for you
Case-insensitive lookups, zero dates, tiny-integer flags, enums, auto-increment keys and views: what the documentation says changes, and which choices belong to you.
Troubleshooting guide
Webpack to Vite: translate the config item by item and treat environment variables as public
Inventory every loader, plugin and setting first, then handle environment variables, require calls and glob imports, and keep the type check that Vite does not run.
Troubleshooting guide
Adopt TypeScript one folder at a time: allowJs, checkJs and a strict area that only grows
How JavaScript and TypeScript coexist, how to find type errors before renaming files, and why strictness is a dial you raise folder by folder.
Troubleshooting guide
Replacing one jQuery or AngularJS feature: write its contract before you touch it
Where support stands for old jQuery and AngularJS, what a feature's hidden contract contains, and how to prove a replacement matches it without rewriting the page.
Troubleshooting guide
Which Node.js line should you move to? Read the project's schedule, then ask your host
Two clocks decide when a Node.js version stops being usable: the project's release schedule and your host's runtime list. How to read both and find every place the version is set.
Troubleshooting guide
Native modules after a Node.js runtime change: what breaks, how to find it and what fixes it
Compiled Node.js add-ons depend on interfaces that stay stable across majors only if they use Node-API. How to find them, test them in a clean install and decide each one.
Troubleshooting guide
Express 4 to 5: test the behaviour changes, not just the methods you rename
The documented Express 5 changes that alter what a route matches, how async errors flow and what request properties contain, with a safe way to check them before upgrading.