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Showing entries 521–560 of 651 in this first collection.
Platform
Next.js app problems: which fault to check first, and which bounded job fits
For a product owner with a working Next.js app that fails in one specific way (sign-in, webhooks, speed, rendering or errors), a map of the usual faults with the checks that separate them.
Platform
React app problems: blank screens, mismatched text, forms and layout, and the job that fits each
For a product owner with a React front end that misbehaves in a specific way, a map from symptom to cause and to a bounded, checkable repair.
Platform
Supabase app problems: empty results, permission errors and where each key belongs
For a product owner whose app is built on Supabase and returns nothing, refuses a write or leaks data, a map of the access-rule faults and the bounded repair that fits.
Inspectable example
Synthetic test-event matrix: eleven named actions and what GA4 DebugView should show
An invented shop and form with a numbered test table, so every tracking claim can be checked with a pass condition. Synthetic example, not a client result.
Inspectable example
Synthetic data layer specification for a small shop: which push, when, with which fields
A one-page specification for five data layer pushes on an invented shop, showing field names, types and the clear-first rule. Synthetic example, not a client document.
Troubleshooting guide
A GA4 key event shows zero: is it not sent, mis-named or not marked?
Separate the three faults that make a GA4 key event count stay at zero, with a DebugView check for each and a note on what reports can and cannot repair.
Troubleshooting guide
Before you delete anything from a Tag Manager container: inventory, preview, then version
A safe order for cleaning up an inherited Tag Manager container: record what each tag sends, watch what fires, change in a workspace and keep a version to return to.
Troubleshooting guide
Google Ads conversion shows Unverified or Inactive: tag, linker, auto-tagging or a lost click ID
What the conversion statuses mean, how the click ID travels from ad to conversion page, where a redirect or missing linker breaks it, and how to test one conversion.
Troubleshooting guide
Meta Purchase event with no value, or counted twice: parameters, deduplication and how to test
What a Meta Purchase event needs, when deduplication applies and when it does not, and how to check one test event with Pixel Helper and Test Events.
Troubleshooting guide
Counting form submissions: the Tag Manager trigger, a custom event, or enhanced measurement?
When each way of detecting a successful form submission works, what Check Validation and Wait for Tags change, and a three-case test per form.
Troubleshooting guide
Server-side tagging for GA4: what the server container does, what a custom domain adds, what it does not fix
How a server container receives and forwards events, why the first-party subdomain matters, how to preview it, and the cost and consent questions to settle first.
Troubleshooting guide
Link Search Console to GA4, and write a one-page measurement plan before you build anything
The permissions, steps, limits and delay for linking Search Console to a GA4 web stream, and a measurement plan template that ties every event to a business question and a test.
Platform
Google Tag Manager: containers, previews and versions for safe tracking changes
How Tag Manager separates a container into workspaces, versions and preview, how the data layer feeds it, and which tracking repairs depend on each part.
Platform
Meta Pixel conversion events: check one test event before you trust the counts
What the Meta Pixel needs for Purchase events, how to see a test event arrive, when deduplication applies and where the Conversions API is a different job.
Buyer collection
For an agency: when Google Ads, Meta and GA4 disagree, check the chain link by link
Find the first broken link between a paid click and a counted conversion, agree what each platform can be compared on, and ask for tests that each client can watch.
Inspectable example
Synthetic record for one slow query: plan, timings and a rows-identical check
An invented before and after record showing what acceptance evidence for a single-query fix contains, including the write-cost line that is often left out.
Buyer collection
For an engineering manager: turn a slow, flaky service into measured data-layer items
Replace theories with a baseline, pick the smallest set of bounded database jobs the baseline supports, and agree acceptance before anyone changes an index.
Troubleshooting guide
A database query is slow: read its plan on a copy before you add an index
How to compare estimated and actual rows, why EXPLAIN ANALYZE runs the statement, and what a before and after measurement must show before a fix counts.
Troubleshooting guide
The index exists but the query still scans the table: check column order, expressions and statistics
Why a database ignores an index: leading columns, expressions that do not match, tiny test tables and stale statistics, and how to test safely without forcing plans in production.
Troubleshooting guide
Jobs reappear or vanish: visibility timeouts, retry counts and dead-letter queues explained
How a queue decides a message is still being worked, when it hands it out again, where failed messages go, and the alarms that stop them sitting unseen.
Troubleshooting guide
A cron job stopped or does nothing: check its environment, mail, percent signs and overlap
Why a command that works by hand fails from cron, how the scheduler treats environment, output, percent signs and day fields, and how to stop runs overlapping.
Troubleshooting guide
Alert when a scheduled job does not run: heartbeat checks, grace time and their blind spots
How a heartbeat monitor inverts alerting, how to choose a schedule and grace time, what start and fail signals add, and what the check cannot see.
Troubleshooting guide
Adding a column to a big table: which steps rewrite it and which locks they take
What PostgreSQL and MySQL do for ADD COLUMN, defaults, NOT NULL, foreign keys and indexes on a large table, and how to order the steps so writes keep flowing.
Troubleshooting guide
Backfill a new column in batches: resume safely and write the rollback first
How to fill a column across millions of rows without one giant transaction, how to prove every row is correct, and how to make the way back reversible and rehearsed.
Troubleshooting guide
Timed out waiting for a database connection: pool size, leaks and server limits are different problems
How to tell an undersized pool from leaked connections, from many processes multiplying the pool, from a pooler mode that breaks features, using SQLAlchemy, Django, PostgreSQL and PgBouncer documentation.
Platform
Redis as a cache: expiry, eviction and invalidation decide whether users see fresh data
For teams using Redis in front of a database: how expiry is cleared by overwrites, what the memory limit does, why persistence is optional for a cache, and which bounded job fits.
Collection
A slow or failing database-backed request: find the first failing layer, in this order
An ordered process map from "the page is slow" to one named cause: query count, one statement, indexes, waits, connections, cache and data shape, each linked to its guide and fixed-scope job.
Collection
A background job or schedule misbehaves: did it run, did it run twice, did it finish?
An ordered process map for scheduled jobs and queue workers: whether the run happened, why it did not, whether it repeated, where failed messages went, and who is told, each linked to a guide and a fixed-scope job.
Troubleshooting guide
Bookings that duplicate or land an hour out in Google Calendar: event identity and time zones
Give each booking a stable Google Calendar event ID so retries never duplicate it, and store the time zone so events show the right local hour across clock changes.
Troubleshooting guide
Why a Google Calendar connection stops working after a week, or months later
The documented reasons a Google refresh token stops working, and how to design a visible reconnect state so bookings are never lost while it is broken.
Troubleshooting guide
Address autocomplete on a checkout: which Google component, which key settings, which fields
Use the current Places autocomplete component, restrict the key to your site and to the Maps JavaScript API and Places API (New), and request only the address fields the form uses.
Troubleshooting guide
Adding Sign in with Google to existing accounts: key on the subject ID and choose a linking rule
Why the provider's subject identifier, not email, identifies a Google user, and three linking rules with the risk each carries.
Inspectable example
Synthetic matrix: Twilio status callbacks arriving in the wrong order, and the stored result each must give
Invented message callback sequences show a forward-only status rule keeping a final state when older statuses arrive late, with the cases an acceptance test should include.
Inspectable example
Synthetic retry traces: waits, attempt limits, a Retry-After date and a timed-out create
Worked arithmetic for a capped, jittered retry policy with invented random draws, plus the records a safe retried write should leave.
Inspectable example
Synthetic booking table: Google Calendar event IDs and local times across clock changes
Five invented bookings show the event ID, zone and UTC offset a sync should write, including a local time that does not exist and one that happens twice.
Buyer collection
For a founder connecting one outside service to an app: ask for one result you can test
Turn 'connect it to Twilio, Slack or Google' into one named result with a test, decide who holds the credentials and pick the single outcome that fits.
Buyer collection
For a small dev team with several outside services: one retry fix, one module or a monthly check
Choose between hardening one failing client, consolidating several services behind one module and keeping a register of credentials, quotas and deprecations.
Collection
A notification did not arrive: check these in order before changing any code
An ordered map from 'the customer says it never came' through the app's own record, the provider's delivery trail, the callback, the recipient's state and the sender set-up, with the guide for each step.
Collection
Accepting a new integration: the order in which to test it before you trust it
An ordered acceptance map for any new connection to an outside service: result, credentials, test route, happy path, failure paths, inbound verification, retries and monitoring.
Troubleshooting guide
SendGrid says the domain is verified, but is your mail actually aligned with your From address?
Read a received message's headers to tell whether SendGrid's SPF and DKIM results match your From domain, and what to check when they do not.