Python sets and dictionaries can have quadratic-time performance https://lemire.me/blog/2026/09/03/python-sets-and-dictionaries-can-have-quadratic-time-performance/
Daniel Lemire
Computer science professor at the University of Quebec (TELUQ), open-source hacker, and long-time blogger. 👨💻
Java’s String.indexOf can be slow (quadratic) https://lemire.me/blog/2026/08/22/javas-string-indexof-can-be-slow-quadratic/
AI programming: a layered model https://lemire.me/blog/2026/09/05/ai-programming-a-layered-model/
Parsing IP addresses in C# at crazy speeds https://lemire.me/blog/2026/08/19/parsing-ip-addresses-in-c-at-crazy-speeds/
The new Go JSON API: twice as fast, or 1.5x slower? https://lemire.me/blog/2026/08/29/the-new-go-json-api-twice-as-fast-or-1-5x-slower/
Memory-level parallelism: AMD is the king https://lemire.me/blog/2026/07/25/memory-level-parallelism-amd-is-the-king/
Go 1.27 will make some allocations cheaper https://lemire.me/blog/2026/08/15/go-1-27-will-make-some-allocations-cheaper/
Using AI to build your own software https://lemire.me/blog/2026/07/16/using-ai-to-build-your-own-software/
AI programming : are you angry yet? https://lemire.me/blog/2026/08/12/ai-programming-are-you-angry-yet/
Profile-guided optimization in Go https://lemire.me/blog/2026/08/09/profile-guided-optimization-in-go/
Chatting with AI Won’t Make You a Top Programmer https://lemire.me/blog/2026/06/21/chatting-with-ai-wont-make-you-a-top-programmer/
A brief history of C/C++ programming languages https://lemire.me/blog/2026/04/09/a-brief-history-of-c-c-programming-languages/
Converting floats to strings quickly https://lemire.me/blog/2026/02/01/converting-floats-to-strings-quickly/
The fastest way to match characters on ARM processors? https://lemire.me/blog/2026/04/19/the-fastest-way-to-match-characters-on-arm-processors/
How many branches can your CPU predict? https://lemire.me/blog/2026/03/18/how-many-branches-can-your-cpu-predict/
Can your AI rewrite your code in assembly? https://lemire.me/blog/2026/04/05/can-your-ai-rewrite-your-code-in-assembly/
Prefix sums at tens of gigabytes per second with ARM NEON https://lemire.me/blog/2026/03/08/prefix-sums-at-tens-of-gigabytes-per-second-with-arm-neon/
Parsing JSON at compile time with C++26 static reflection https://lemire.me/blog/2026/06/14/parsing-json-at-compile-time-with-c26-static-reflection/
How stagnant is CPU technology? https://lemire.me/blog/2026/01/14/how-stagnant-is-cpu-technology/
How much do amd64 microarchitecture levels help in Go? https://lemire.me/blog/2026/06/06/how-much-do-amd64-microarchitecture-levels-help-in-go/
How bad can Python stop-the-world pauses get? https://lemire.me/blog/2026/02/15/how-bad-can-python-stop-the-world-pauses-get/
Embodied cognition and agentic AI https://lemire.me/blog/2026/05/28/embodied-cognition-and-agentic-ai/
A new way to call C from Java: how fast is it? https://lemire.me/blog/2026/01/17/a-new-way-to-call-c-from-java-how-fast-is-it/
A bit of glass and freedom is all you need https://lemire.me/blog/2026/01/07/a-bit-of-glass-and-freedom-is-all-you-need/
JSON and C++26 compile-time reflection: a talk https://lemire.me/blog/2026/03/26/json-and-c26-compile-time-reflection-a-talk/
Text formats are everywhere. Why? https://lemire.me/blog/2026/03/05/text-formats-are-everywhere-why/
You can use newline characters in URLs https://lemire.me/blog/2026/02/28/you-can-use-newline-characters-in-urls/
How fast do browsers correct UTF-16 strings? https://lemire.me/blog/2026/02/21/how-fast-do-browsers-correct-utf-16-strings/
AI: Igniting the Spark to End Stagnation https://lemire.me/blog/2026/02/15/ai-igniting-the-spark-to-end-stagnation/
Converting data to hexadecimal outputs quickly https://lemire.me/blog/2026/02/02/converting-data-to-hexadecimal-outputs-quickly/
What I Got Wrong About “Hard Work” in My 20s https://lemire.me/blog/2026/01/08/what-i-got-wrong-about-hard-work-in-my-20s/
Models and science https://lemire.me/blog/2025/05/23/models-and-science/
The ancient Greeks crafted extraordinary models that continue to resonate. For instance, P
From Institutions to Individuals: the White House Report on Revitalizing U.S. Scientific Leadership https://lemire.me/blog/2026/07/22/from-institutions-to-individuals-the-white-house-report-on-revitalizing-u-s-scientific-leadership/
A quick overview of atomics in C https://lemire.me/blog/2026/09/09/a-quick-overview-of-atomics-in-c/
X just gave us an interface that AI agents can use. I pointed it at my own posts. https://lemire.me/blog/2026/07/11/x-just-gave-us-an-interface-that-ai-agents-can-use-i-pointed-it-at-my-own-posts/
Optimizing Python scripts with AI https://lemire.me/blog/2026/01/25/optimizing-python-scripts-with-ai/






