/Time Data

How To Think About Time

- Kevin Bourrillion tl;dr: “The Java And Kotlin Ecosystem team at Google has worked for several years to eliminate the sources of date / time bugs in Google’s codebase. We’ve learned a lot from this. But my goal here is not to provide a laundry list of programming practices. It’s more basic than that. I hope to provide a solid “conceptual model” for how we think about date and time concepts in the most helpful way. I’m shooting for it to be understandable, usable, and to avoid saying things that are egregiously wrong.”

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Storing Times For Human Events

- Simon Willison tl;dr: “I’ve worked on various event websites in the past, and one of the unintuitively difficult problems that inevitably comes up is the best way to store the time that an event is happening. Based on that past experience, here’s my current recommendation.”

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Australia / Lord_Howe Is The Weirdest Timezone

- Ulysse Carion tl;dr: “The standard trope when talking about timezones is to rattle off falsehoods programmers believe about them. These lists are only somewhat enlightening – it’s really hard to figure out what truth is just from the contours of falsehood. So here’s an alternative approach. I’m gonna show you some weird timezones. In fact, the weirdest timezones. They’re each about as weird as timezones are allowed to get in some way.”

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Introducing Netflix’s TimeSeries Data Abstraction Layer

tl;dr: Netflix developed the TimeSeries Abstraction — a versatile and scalable solution designed to efficiently store and query large volumes of temporal event data with low millisecond latencies, all in a cost-effective manner across various use cases. “In this post, we will delve into the architecture, design principles, and real-world applications of the TimeSeries Abstraction, demonstrating how it enhances our platform’s ability to manage temporal data at scale.”

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Test Clocks: How We Made It Easier To Test Stripe Billing Integrations

- Ji Huang tl;dr: Test Clocks simulates the passage of time in billing scenarios without waiting for actual seconds to tick by in the real world. This blog discusses the technical details of how Stripe built test clocks, and how they updated systems to account for the different ways that time passes. 

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Falsehoods Programmers Believe About Time Zones

- Zain Rizvi tl;dr: 22 misconceptions, starting with: (1): UTC offsets go from -12 to +12. (2) Every UTC offset corresponds to exactly one time zone. (3) There are more countries in the world than time zones - there are 244 time zones used by the 195 countries in the world. (4) Every time zone has exactly one agreed upon name. (5) Time zones are always offset from UTC by an integer number of hours. 

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The 2038 Problem

tl;dr: “”The 2038 problem" relates to an issue with how Unix-based systems store dates and timestamps. Most Unix systems use a 32-bit signed integer to represent the number of seconds since January 1st, 1970. This is known as the Unix epoch or Unix time. The core of the issue is that a 32-bit variable can only store integers up to 2147483647. Once the system clock ticks past this at 03:14:07 UTC on January 19, 2038, it will integer to overflow, setting its value to −(231).” 

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35 Misconceptions About Date And Time

- Gérald Barré tl;dr: (1) Everybody uses the same calendar. (2) 1 year equals 12 months. (3) GMT is the same as UTC. (4) Time zone offsets are always integer numbers of hours. (5) Weeks start on Monday. And more.

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Hate Leap Seconds? Imagine A Negative One

- Randy Au tl;dr: Earth's rotation, relative to the fixed stars, has sped up and is predicted to continue to do so. Although there are no immediate implications, if it continues over a sustained period of time, we might find ourselves having to consider a negative leap second, as explained here.

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The Largely Untold Story Of How One Guy In California Keeps The World’s Computers Running On The Right Time Zone. (Well, Sort Of)

- Daniel Rosehill tl;dr: "Brief odyssey into the esoteric world of the tight-knit time zone data maintenance community who quietly keep the world’s computers from avoiding DST-related-meltdowns."

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