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Front-page articles summarized hourly.

Bipartisan Bill to Tighten Controls on Sensitive Chipmaking Equipment

Congressman Michael Baumgartner introduced the bipartisan MATCH Act to tighten export controls on semiconductor manufacturing equipment (SME) and counter China. It would ban chokepoint SME to countries of concern, extend controls to major Chinese fabs (CXMT, Hua Hong, Huawei, SMIC, YMTC), and require allied alignment with a 150-day deadline; if allies fail, the U.S. could act unilaterally. It uses the Foreign Direct Product Rule and includes a National Security Waiver to extend negotiations. A companion Senate bill exists. Endorsements emphasize protecting jobs, innovation, and national security.

The becquerel as an SI unit for request rate

Argues that request rate must be tied to a fixed period (preferably one second) and reported as requests per second. Explains two SI candidates: Hz (one event per second) and Bq (also one event per second). Hz fits highly regular loads; Bq suits stochastic traffic via Poisson-like arrivals. Recommends 500 Hz for regular load testing, 500 Bq for typical traffic, and notes convenience of 'kBq' over 'k requests/s'. A reader suggested 'rips' for a unit, but there is no general SI unit for arbitrary events; author will keep using Bq.

What Are Skiplists Good For?

Skiplists generalize to a 'skiptree'—a tree of skiplists enabling fast ancestor queries over huge, tree-structured logs from fault-injection runs. Antithesis faced slow point lookups in BigQuery when walking ancestors one by one. They stored each tree level in its own SQL table with next_level_ancestor and ancestors_between, enabling a single fixed-height, non-recursive join to retrieve all ancestors. It worked but required large, hand-written SQL; later they built Pangolin, their own tree database, to run these queries efficiently. Takeaway: exotic data structures can save time and money.

Dizzying Spiral Staircase with Single Guardrail Once Led to Top of Eiffel Tower

Could not summarize article.

Bypassing the kernel for 56ns cross-language IPC

The Tachyon ADR directory hosts Architecture Decision Records for Tachyon. Each ADR documents a key design choice, its motivating context, decision, and consequences, using a standard template. The index shows several ADRs (ADR-001 memfd_create vs shm_open; ADR-002 SPSC vs MPSC; ADR-003 Futex vs eventfd; ADR-004 msg alignment 64; ADR-005 SCM_RIGHTS vs named mmap; ADR-006 No-serialization contract) all with Status and Date (Accepted 2026-03-30). ADRs are permanent records; superseded decisions are linked; templates include Context, Decision, Consequences.

Updating Gun Rocket through 10 years of Unity Engine

Could not summarize article.

Show HN: Sostactic – polynomial inequalities using sums-of-squares in Lean

sostactic is a Lean4 toolkit and Python backend for proving polynomial inequalities using sum-of-squares certificates. It enables global nonnegativity and semialgebraic-set reasoning via tactics (sos_decomp; putinar_decomp; schmudgen_decomp) and emptiness checks (putinar_empty; schmudgen_empty). It can be used from Lean, Python API/CLI, or via certificates loaded from JSON. It relies on cvxpy for SDP, with exactification to produce exact certificates. It supports denominators and basis overrides; failures suggest higher order, alternative theorems (Putinar/Schmüdgen) or pre-generated certificates. Requires Lean Mathlib and Python 3.10+. MIT license.

My first impressions on ROCm and Strix Halo

First impressions of ROCm with Strix Halo on Ubuntu 24.04 LTS: 128 GB shared memory between CPU/GPU, BIOS update required for PyTorch detection, and GRUB tweaks (ttm.pages_limit, amdgpu.gttsize) to enable shared memory with CPU reserves (4–12 GB). The post covers PyTorch-ROCm setup via uv, a Podman/Llama.cpp workflow for Qwen-3.6 with large context, and model download/conversion steps. Conclusion: it works—PyTorch runs and Qwen-3.6 with a large context window is playable, with some rough edges but worthwhile.

Zero-Copy GPU Inference from WebAssembly on Apple Silicon

Apple Silicon’s Unified Memory lets a Wasm module’s linear memory be shared directly with the GPU, enabling zero-copy inference. The chain: mmap page-aligned memory; Metal buffers can wrap the pointer without copying; Wasmtime’s MemoryCreator lets Wasm use that memory. A 128×128 GEMM validated zero-copy (pointer identity, negligible RSS delta) with ~6.75 ms latency, same as copy path. Running Llama 3.2 1B from Wasm via MLX gave ~9 ms per token; serialize/restore of KV cache via safetensors yields 5.45× speedup over recompute and bit-identical results. Driftwood aims to portable, stateful Wasm actors with model swaps and snapshots; early but working.

A story about how I dug into the PostgreSQL sources to write my own WAL receiver

Could not summarize article.

Dad brains: How fatherhood rewires the male mind

Fatherhood triggers biological changes in men, not just social roles. Expectant fathers show lower testosterone and vasopressin before birth; postnatally, greater caregiving links to lower testosterone and higher bonding hormones such as oxytocin and prolactin. Brain imaging finds neural changes during the transition, shaping responses to infants. Involvement level drives the degree of change, supporting Hrdy’s idea of an alloparental substrate. Findings span straight and gay fathers. Public policy should bolster dads’ involvement and leave. A large 7-year study found children of more attentive fathers have better heart health, underscoring paternal biology’s family benefits.

NASA Shuts Off Instrument on Voyager 1 to Keep Spacecraft Operating

NASA's Jet Propulsion Laboratory shut down the Low-energy Charged Particles instrument (LECP) aboard Voyager 1 to conserve power as the probe's energy margins thin. Launched in 1977 and now over 15 billion miles from Earth, Voyager 1 loses about 4 watts per year. The LECP shutdown will take about 23 hours to reach Voyager 1 and roughly 3 hours to complete; a small LECP motor (0.5 W) will stay on in case it can be reactivated. Two other instruments remain active. A broader "Big Bang" energy-saving upgrade will be tested first on Voyager 2, then Voyager 1 if successful.

In the AI propaganda war, Iran is winning

Could not summarize article.

Modern Common Lisp with FSET

Scott L. Burson’s Modern Common Lisp with FSet is a CC BY-NC-SA 4.0 guide to FSet, a functional-collections library for Common Lisp. It covers why FSet was created, benefits of functional data structures, and hands-on material: getting started, tutorials for Sets, Maps, Seqs, Bags, nesting, assignment, importing, and Emacs tips. It also presents conceptual background, design of FSet (equality, data structures, time complexity), a comprehensive API (sets, maps, bags, sequences, replay structures), iterators, printing/JSON, and examples (histograms, graph walking). The document includes recommendations for language designers and historical critiques of other libraries.

Optimizing Ruby Path Methods

The post outlines optimizing Ruby startup time in CI by shortening the setup phase with Bootsnap and faster path handling. Bootsnap caches load-path entries for near-constant-time requires, using mtimes for cache invalidation. A key win came from adding Dir.scan to walk load paths with file-type info, delivering about a 2x directory-scanning speedup and informing a Ruby 4.1 feature. The author also slimmed File.join and other path methods: added ASCII fast paths, inlined C, reduced allocations, and replaced rb_string_value_cstr with rb_str_null_check. Benchmarks show substantial gains in path-related operations.

Any Color You Like: NIST Scientists Create 'Any Wavelength' Lasers

NIST researchers have created integrated photonics chips that generate multiple laser colors on a single chip by stacking nonlinear materials on silicon. The 3D circuits use lithium niobate and tantalum pentoxide (tantala) with metal interfaces to convert, route, and switch light across many wavelengths. They demonstrated about 50 fingernail-sized chips on a wafer, each with roughly 10,000 circuits outputting a unique color. The approach could miniaturize bulky lasers, aiding quantum clocks/computers, AI, navigation, biomedicine and communications. Nature paper; collaboration with Octave Photonics.

PgQue: Zero-Bloat Postgres Queue

PgQue is a zero-bloat, pure-SQL Postgres queue that reimplements PgQ for PostgreSQL 14+ without C extensions or external daemons. It ships as a single sql/pgque.sql file and runs on managed Postgres (RDS, Aurora, Cloud SQL, AlloyDB, Supabase, Neon). It uses pg_cron (or your own scheduler) to tick every second, delivering snapshot-based batching with TRUNCATE rotation to avoid dead tuples. It offers language-agnostic SQL API, per-consumer cursors with fan-out, ACID durability, and modest end-to-end latency (~1–2 seconds). Roles: pgque_reader, pgque_writer, pgque_admin; client libraries in Python/Go/TypeScript.

PostgreSQL production incident caused by transaction ID wraparound

An in-production PostgreSQL outage was caused by transaction ID wraparound, where aging XIDs can silently near a 2‑billion limit and cause a hard stop on writes to prevent corruption. Autovacuum had been disabled on some tables for years, allowing relfrozenxid to age; others continued, letting the risk accumulate across the cluster. Recovery required aggressive VACUUM FREEZE and terminating long-running transactions. Root cause: long‑standing configuration decisions and disabled autovacuum; similar risks existed across systems. Unlike PostgreSQL, SQL Server uses LSNs and does not halt writes for wraparound.

Floating Point Fun on Cortex-M Processors

Floating Point Fun on Cortex‑M Processors explains how ARM Cortex‑M FPU support is exposed via ABI variants (-mfloat-abi): soft, softfp, and hard. It shows how hard ABI uses FP registers for argument passing and may call runtime FP functions for soft operations; soft and softfp mix with hard can trigger linker errors. It covers how to inspect ABI attributes with readelf and how Zephyr config (CONFIG_CPU_HAS_FPU, CONFIG_FPU) controls FPU enablement, including dynamic init via z_arm_floating_point_init and CPACR/FPCCR/FPSCR setup. It warns that using FP without enabling the FPU causes NOCP faults and discusses use cases for toggling FP hardware.

Rail: A self-hosting language that speaks TLS alone

Rail is a self-hosting systems language with zero C dependencies, whose ARM64-assembly GC and runtime live inside the compiler. As of v3.0.0 it includes a pure-Rail TLS 1.3 stack with X.509 chain validation and a native HTTPS client (no OpenSSL or curl). The compiler can bootstrap itself to byte-identical, targets macOS ARM64, Linux ARM64, Linux x86_64, and WASM, and ships four backends. The project also uses a self-improving flywheel: the compiler acts as the training signal for LLM-driven training loops. License: BSL 1.1.

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