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"Passkeys are a trap" got over 1,100 points on Hacker News. Its advice: go back to a password and a 6-digit code.

A phishing kit relays that code as you type it. Troy Hunt got phished exactly this way.

A passkey is never typed, and your browser only offers it on the real domain.

https://t.co/7Ko6d2Z2uT

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A passing Spark job proves its config worked, not that it needed it. Over-provisioned jobs keep passing.

Salesforce traced eight million runs a day, found executors completing zero tasks, and trimmed allocations. Targeted weekly compute cost fell 31%.

https://t.co/l4y5zBkopx

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Cloudflare's analytics data nearly doubles every year. Its hardware doesn't.

So the data team moved sampling and counting onto every server, and made the second region's copy last, after the data had shrunk. 70 GB/s off the network.

https://t.co/JR4wUd3FaY

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NTP replies carry no signature. Clients trust whatever answer arrives first, and certificate expiry trusts that clock.

Meta runs NTS: time packets authenticated with TLS-derived keys, carried in cookies any server can open by re-deriving the day's key.

https://t.co/lcycGTVVNZ

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CLI tables are padded for humans; truncation notes are easy to miss. Agents pay tokens for padding and may reason from rows they never saw.

DuckDB's CLI detects agents and prints compact Markdown with explicit truncation: 59% fewer output tokens read.

https://t.co/IFsx4Xs6er

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Anthropic merges 30,000 changes a day, so it replaced git.

Git gives every clone the whole repo to work offline. Anthropic's clients are agents and jobs that never go offline.

Scion keeps the repo on the server; clients ask for what they need.

https://t.co/JR4wUd3FaY

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Bulk loading a terabyte into Postgres funnels every row through one writer, the primary serving live queries.

Databricks has Spark build the heap pages in object storage and swaps them in with one WAL record. Loading 1 TB takes less than 5 minutes.

https://t.co/qi9pVOxWkD

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A 125B-parameter model is running on a 12 GB gaming card.

Each layer is 512 blocks of weights, called experts, and only ten run per token. Strata caches the popular ones on the GPU and the CPU computes the rest from RAM.

94 tokens/s, heavily compressed.

https://t.co/JR4wUd3FaY

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A circuit breaker's probes test a service at its quietest: the autoscaler shrank it while the breaker was open. Probes pass; full traffic hits a cold fleet.

Zalando found one stuck in that loop for hours, blocking 95% of traffic. Pre-scaling broke it.

https://t.co/hN8AfKLCmC

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Retries are how one struggling service turns into a full outage.

One retry per hop, and a failing service four deep gets 8x its traffic.

Uber's fix: every error carries a header saying whether its sender caused it. Callers only retry the ones it did.

https://t.co/JR4wUd3FaY

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Datadog made its Python profiler cheaper by letting it segfault.

It used to make a system call on every read. Now it copies memory directly, catches the SIGSEGV, and drops that one sample. Overhead fell over 60% on Datadog's own services.

https://t.co/JR4wUd4d0w

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GROUP BY on a string column makes DuckDB hash every byte of every row, then follow a pointer to compare the full string.

The fix: give each distinct string a narrow integer key in a dimension table, aggregate on the key, and join the names back last.

https://t.co/g4TWxZUflO

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You might run GTA 6 on PC before Rockstar ports it.

AnyPS5 doesn't emulate a PS5. It keeps the game's code, rebuilds the executable around it, and swaps Sony's system libraries for native ones your OS loader binds by hash.

One game verified so far.

https://t.co/JR4wUd3FaY

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Hash several inputs by concatenation and the boundaries vanish: different sequences give the same SHA-256 digest.

Trail of Bits' SequenceHash appends each input's length as a fixed 128-bit integer, so every sequence encodes one way. Rust, Go and Python.

https://t.co/yDu0WNiDwI