AI 资讯
One View Per Layer: Four Sharp Edges I Found in My Own Code
There is a layer in my database called 1 . Somebody created it, presumably by accident, and it sat there for months looking harmless. It was the only layer in the system that never served a single tile, and nobody noticed, because it was empty anyway. That layer turned out to be a symptom of a SQL injection vulnerability. This post is about the design that produced it — which I still think is a good design — and the four things I got wrong inside it. The setup A web GIS with about 2.7 million features: 1.8 million points, 697,000 lines, 172,000 polygons. Users create layers through the UI, upload data into them, edit geometry, and expect to see it on a map. The features do not live in a table per layer. They live in three tables — one for points, one for lines, one for polygons — with a layer_id foreign key and a JSON column for attributes: project_pointfeature 1,820,288 rows project_linefeature 697,009 rows project_polygonfeature 171,830 rows That's a deliberate trade. A table per layer means DDL every time a user clicks "new layer", a migration story that never ends, and a schema that drifts. Three generic tables mean one schema, one set of indexes, and layers that are just rows in a metadata table. The cost lands on the tile server. The pattern Martin serves vector tiles from PostGIS. Point it at a database and it discovers spatial tables and views and publishes each as an MVT endpoint. It can be told to publish views but not tables: postgres : auto_publish : from_schemas : [ public ] publish_tables : false reload_interval : 5s So: give every layer its own view. A Django post_save signal on the Layer model creates it: CREATE OR REPLACE VIEW t19_saobracajni_znakovi AS SELECT f . id , f . feature_attrs , f . geom , f . layer_id , l . name AS layer_name , lg . name AS layer_group_name , p . title AS project_title FROM project_pointfeature f JOIN project_layer l ON f . layer_id = l . id JOIN project_layergroup lg ON l . layer_group_id = lg . id JOIN project_project p
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De-Googled GrapheneOS is coming to Motorola’s foldables next year
GrapheneOS, an open source version of Android that prioritizes security and privacy, has detailed its plans for supporting Motorola smartphones. Official support is set to arrive next year, starting with traditional flagships, before rolling out to Motorola's foldable phones and perhaps cheaper models, eventually. In a Mastodon thread, the GrapheneOS Foundation announced that it will […]
开发者
Criminal Deception in Silicon Valley
Interesting paper : Abstract: With entrepreneurial fraud cases on the rise, we investigate how entrepreneurs carry out criminal deception , employing deceptive means to defraud audiences. Analyzing court data from Silicon Valley ventures and their founders prosecuted for fraud between 2000 and 2023, our findings reveal that entrepreneurs carry out criminal deception through a process of façading : Entrepreneurs construct, perform, and protect illusory appearances (façades) that externally project high-growth performance to audiences while masking ventures’ actual underperformance. We identify three forms of façading—surface, reinforced, and deep façading—that are contingent on the severity of the gap that entrepreneurs face between audiences’ performance expectations and ventures’ performance reality. Our theoretical framework captures how entrepreneurs facing minor, wide, and extreme expectation-reality gaps engage in evermore sophisticated efforts to detach the venture’s externally projected appearance from its actual operational reality. Practically, we propose several approaches to deter and detect criminal deception, including the extension of U.S. Securities and Exchange Commission surveillance and whistleblower program, investor due diligence reform, and dedicated entrepreneurship education interventions that clearly demarcate when entrepreneurs transgress into criminal deception. We make contributions to literatures on cultural entrepreneurship, organizational wrongdoing, and the social effects of entrepreneurship. ...
AI 资讯
SSE in Go: Your Timeouts Do Not Apply Where You Think
An SSE stream is an HTTP request that never ends. Every default you did not touch is working against it. TL;DR : your SSE endpoint breaks twice before it reaches your logic. Once because the Connection header is illegal in HTTP/2. Once because your Go server's default timeouts cut the stream at 30 seconds. And if you stay on HTTP/1.1, a permanent stream freezes the rest of your page. In August 2026, Go patched a flaw where a timeout was not applied to HTTP/2 connections. Same lesson: a timeout only protects what it covers. This article is for Go developers shipping streaming to production. SSE, WebSocket, long-poll: anything that stays open. The setup SSE stands for Server-Sent Events. It is a one-way HTTP stream. The server pushes messages, the browser listens. The format is simple. You open a text/event-stream response, you write lines, you flush. The browser receives them as they come. I run two SSE endpoints in production. The first is a Go notification service, on Kubernetes, behind a reverse proxy. The second is an internal cockpit that refreshes its UI without a page reload. Both broke. In different places, with the same symptom. An SSE stream is a request that never ends Here is the key to the whole article. To your server, an SSE stream is not a special case. It is a very slow request. And every guardrail in an HTTP server targets the slow request. Write timeout, context timeout, idle timeout. They exist to kill whatever drags on. Your legitimate stream looks exactly like what they are meant to kill. That is the whole problem. The Connection header is illegal in HTTP/2 First incident. The endpoint answers 200, then the browser shows net::ERR_HTTP2_PROTOCOL_ERROR . The client reconnects in a loop. The cause was one line. My handler set a Connection: keep-alive header. We all copy it from some old SSE tutorial. Connection is a hop-by-hop header. A hop-by-hop header applies to one network hop only, never end to end. HTTP/2 forbids these headers (RFC 9113 §8.2.
AI 资讯
Leetcode 31: Next Permutation
Question : Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order). The replacement must be in-place and use only constant extra memory. Here are some examples. Inputs are in the left-hand column and its corresponding outputs are in the right-hand column. Example : 1,2,3 → 1,3,2 3,2,1 → 1,2,3 1,1,5 → 1,5,1 Idea : Scan from right to left and find the first element that is less that its previous. eg: 1 6 3 5 -> here it is 3. Let's name it as index. Again scan from right to left and find the first element that is greater than 3 and that's 5. Let's mark it as idx. 3.In this step we swap 3 and 5. Reverse elements from index+1 till the array length. Code: public void nextPermutation(int[] nums) { int index = -1; for(int i=nums.length-1;i>0;i--){ if(nums[i]>nums[i-1]){ index = i-1; break; } } if(index==-1){ reverse(nums,0,nums.length-1); return; } int idx=0; for(int i=nums.length-1;i>=index+1;i--){ if(nums[i]>nums[index]){ idx=i; break; } } swap(nums,index,idx); reverse(nums,index+1,nums.length-1); } void swap(int[] nums,int i,int j){ int temp =nums[i]; nums[i] = nums[j]; nums[j] = temp; } void reverse(int[] nums,int i ,int j){ while(i<j){ swap(nums,i,j); i++; j--; } } Code Explanation : We first initialize index=-1 and traverse backward to find the first one with i that satisfy the condition nums[i]>nums[i-1] . We assign this to index and break out of the loop. for(int i=nums.length-1;i>0;i--){ if(nums[i]>nums[i-1]){ index = i-1; break; } } Next step we are discussing a corner case. For example if the given array is 3,2,1 then we cannot find the element that satisfies the previous condition. So when the array is given in decreasing order we just reverse it and return. if(index==-1){ reverse(nums,0,nums.length-1); return; } Next iteration we are considering another variable idx and traverse backw
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Construyendo un recomendador de emparejamiento de expertos
La forma del problema Un directorio es una superficie: el miembro lo abre y adivina. Un recomendador es una superficie de empujar: el sistema propone y tiene que justificarse. La justificación es la parte difícil, y es donde vive la estadística. Tres restricciones hicieron esto distinto de un recomendador de contenido: El item es una persona con capacidad finita. Un hilo se le puede recomendar a diez mil personas. Un experto no. Una mala recomendación es cara de los dos lados. Quien pide desperdicia una petición, el experto desperdicia una hora, y los dos aprenden a ignorar la superficie. La afirmación tiene que ser checable. "Quizá te guste este hilo" no necesita evidencia. "Esta persona está un nivel adelante de ti en diseño de sistemas" sí. Recuperación: híbrida, fusionada con RRF Tres recuperadores independientes sobre el conjunto de expertos elegibles, fusionados con Reciprocal Rank Fusion: def rrf_fuse ( * ranked_lists , k = 60 ): """ Fusiona listas de ids rankeadas. El score depende solo del rank, nunca de la escala propia del recuperador, que es el punto: la similitud coseno y un conteo de hilos resueltos no son números comparables. """ fused = {} for lst in ranked_lists : for rank , key in enumerate ( lst ): fused [ key ] = fused . get ( key , 0.0 ) + 1.0 / ( k + rank ) return fused RRF es la primitiva correcta aquí por una razón que vale la pena decir: los recuperadores emiten cantidades incomparables. Uno regresa un coseno en [-1, 1] , uno regresa un conteo entero de hilos resueltos, uno regresa un delta de nivel de escalera. Normalizarlos a una escala común requiere supuestos sobre sus distribuciones que nadie tiene a este volumen de datos. RRF descarta las magnitudes y se queda solo con el orden, que es exactamente la información que sobrevive a una muestra chica. k = 60 es la constante estándar de la formulación original de Cormack et al. Aplana la cabeza: la diferencia entre el rank 1 y el rank 2 es 1/61 - 1/62 ≈ 0.00026 , así que un recuperador no pu
产品设计
How is Android Auto different from Android Automotive?
While these two names sound like they'd refer to the same product, there are major differences between them.
创业投融资
Uber faces fine of nearly $1B over automated driver suspensions
The Dutch Data Protection Authority is fining Uber €825 million in the second largest penalty issued under Europe’s GDPR.
科技前沿
These modern smartwatches are in their last year of updates
A whole bunch of smart watches are getting phased out this year. Is your watch on the list?
科技前沿
Flock CEO calls for ‘compromise’ as surveillance company faces growing backlash
Flock Safety faces a growing public outcry over concerns that its surveillance technology could be misused.
AI 资讯
Why Fixed-Window Rate Limiters Fail (And How to Fix Them with Math)
If you’ve ever built an Express API, you’ve probably reached for standard rate-limiting middleware to protect your login or payment endpoints from DDoS and brute-force attacks. Under the hood, most simple limiters use a Fixed-Window Counter . It’s easy to write: count incoming requests, and once the minute rolls over, reset the counter to zero. However, from a security and algorithmic standpoint, Fixed-Window counters have a massive blind spot. The Boundary Vulnerability (The 2-Second Spike) Imagine your endpoint allows a maximum of 100 requests per minute , resetting every full minute on the clock ( :00 ). Here is how an attacker bypasses that limit without breaking your rules: At 12:00:59 , the attacker fires 100 requests. (Allowed: 100/100 used). At 12:01:00 , the clock resets your counter back to 0. At 12:01:01 , the attacker fires another 100 requests. (Allowed: 100/100 used). To your server code, everything looks fine. But in reality, 200 requests slammed your backend within a 2-second window. In FinTech or authentication systems, that burst is more than enough to overwhelm payment gateways or run a successful credential-stuffing attack. The Algorithmic Fix: Sliding Window Counter To stop boundary spikes, we need a continuously sliding window rather than a rigid clock reset. Attempt 1: The Sliding Window Log (High Memory) You store a timestamps array (a Deque) for every user request and drop timestamps older than 60 seconds. While accurate, storing every single request timestamp takes $O(N)$ space. If your API receives millions of requests, your server memory dies instantly. Attempt 2: Sliding Window Counter (Optimal O(1) Math) Instead of keeping thousands of timestamps, we track only two integers : the request count of the previous window and the count of the current window . When a request arrives, we calculate an estimated request count by weighting the previous window based on how much time has passed in the current window: Estimated Requests = Current Cou
AI 资讯
When Python is Too Slow
Python is a perfect language for Agile development, where requirements might change on the go. Especially if you are in a startup business, you will need to experiment and change things fast. However, Python is an interpreted language, and in certain situations you might need faster performance than what an interpreted language can provide. A common practice in these cases is using python-to-binary bindings, where the binary code is built with Rust, C++, or Go. In this article, I will explore bindings to Rust-based code. How do the bindings work The idea behind bindings is that you create a module with functions of a specific domain in a language that compiles to binary, and build it as a C-compatible dynamic library ( .so on Linux, .dylib on macOS, .dll on Windows). Then a Python wrapper is built as a Python package and installed together with the dynamic library, allowing you to import and use functions that pass control to the corresponding functions in the dynamic library. On some occasions, classes can be used instead of functions. If any parameters are complex, they must be serialized in the wrapper and passed to the dynamic library as a JSON string or as a set of individual primitive parameters. An experiment with benchmarks To try this Python-Rust communication, I vibe coded an experiment that reads a large CSV file and builds a new one with duplicates stripped out based on specified column indexes. In my test case, it was a 3 MB CSV file with data about European NGOs for the donation platform I am building, where I wanted to remove the NGOs that don't have website URLs listed. As benchmarked, the file was processed 4.3x faster with the Rust binding than directly with Python. Here is the repo to get a first glimpse into the code and structure. What is there to know about Rust A few things about Rust: Rust packages are built with Cargo, which is the equivalent of pip, virtualenv, and setuptools combined. A single package is called a crate, and it can be publi
开发者
How to Build a Real-Time Google Docs for Code
What happens when two developers edit the EXACT same line of code at the EXACT same millisecond? Race conditions, overwritten data, and a crashed server. Today, we’re tearing down the magic behind Figma and Google Docs to build a real-time collaborative code editor using Next.js 16 and CRDTs ⏱️ CHAPTER 1: The Collaborative Text Editing Trap "Building a single-user code editor is simple: a React state variable, a text area, and a save button.But the moment two developers open that same code file at the exact same millisecond... everything breaks. User A types a function name at index 5, while User B deletes a line at index 2. If you simply push text updates to a database over HTTP, you get catastrophic race conditions, overwritten code, and cursor teleportation.So, how do platforms like Google Docs, Figma, and Replit allow thousands of users to type simultaneously in real-time without locking files or destroying data? Welcome back to Behind the Abstraction. Today, we’re building a real-time collaborative code editor using Next.js 16. We’ll strip away the magic of real-time state, compare Operational Transformation vs CRDTs, and implement WebSocket edge routing using modern Full-Stack architecture." ⏱️ CHAPTER 2: OT vs CRDTs - The Core Math of Real-Time "Before writing a single line of Next.js code, we must solve a fundamental computer science problem: Mathematical Consistency across Distributed Systems.There are two primary ways to resolve typing conflicts: Operational Transformation (OT): Used by classic Google Docs. Every keypress sends an 'operation' (like Insert "a" at index 10) to a central server. The server acts as the absolute referee, transforming index positions and broadcasting the fix back to all clients. The Problem: Centralized OT servers are complex, memory-heavy, and difficult to scale horizontally at the Edge. CRDTs (Conflict-free Replicated Data Types): Used by modern tools like Figma and VS Code Live Share. Instead of raw array indexes, every chara
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Will the DOJ’s investigation into a16z spook other VCs?
On the latest episode of Equity, we wonder why the DOJ is investigating startup board seats.
AI 资讯
Inherent, founded by DeepMind alumni, says its AI ‘teammate’ just outperformed Anthropic and OpenAI at replicating research
Built by DeepMind alumni, British AI lab Inherent released Faraday, an AI agent whose ability to replicate scientific papers could be a stepping stone for innovation.
AI 资讯
Enterprise vibe coding: the governance framework for shipping AI-generated apps to production
Enterprise vibe coding: the governance framework for shipping AI-generated apps to production Published: August 22, 2026 Category: Enterprise · AI Deployments Reading time: 9 minutes Author: NEXUS AI Team Gartner forecasts that 40% of new enterprise production software will be built using vibe coding techniques by 2028. A 2026 scan of more than 1,400 live vibe-coded applications found that 65% already had a security issue, and 58% shipped with at least one critical vulnerability. Those two numbers describe the same industry moving in opposite directions at once: adoption is outrunning governance. This post covers what a governance framework for enterprise vibe coding actually looks like, the five controls it needs, and where most teams get it wrong. What is enterprise vibe coding? Enterprise vibe coding is the practice of using natural-language prompts to generate application code, then governing that code through mandatory review, access control, and audit before it reaches production, rather than letting it ship straight from a prompt to a live endpoint. The term (coined by Andrej Karpathy in early 2025) originally described a fast, low-friction way for one person to build a prototype. What "enterprise" adds is the governance layer prototyping was never built for: staging environments, encrypted secrets, role-based access, and a record of who approved what. That distinction matters because the adoption curve and the risk curve are not moving together. The governance gap, in three numbers 40% of new enterprise production software will be built using vibe coding techniques by 2028, according to Gartner's May 2025 report "Why Vibe Coding Needs to Be Taken Seriously," as reported by CIO Dive . 65% of vibe-coded production applications had a security issue, in a 2026 scan of more than 1,400 live apps by the API security firm Escape.tech, reported via a Cloud Security Alliance research note . 58% of those same applications shipped with at least one critical vulnerabilit
科技前沿
Android Auto YouTube Limitations: Is It Worth Using In The Car?
Android Auto YouTube Limitations: Is It Worth Using In The Car?
AI 资讯
OpenAI says California should strengthen its AI safety bill
OpenAI is calling for California to strengthen SB 53, an AI safety bill that the company previously opposed.
开源项目
🔥 Wei-Shaw / sub2api - Sub2API 一站式开源中转服务,让 Claude、Openai 、Gemini、Grok订阅统一接入,支持拼车共享,
GitHub热门项目 | Sub2API 一站式开源中转服务,让 Claude、Openai 、Gemini、Grok订阅统一接入,支持拼车共享,更高效分摊成本,原生工具无缝使用。 | Stars: 38,723 | 264 stars today | 语言: Go
AI 资讯
Frontier AI labs still won’t say how they’d contain a rogue model
A new study finds leading AI labs have few publicly documented plans for containing rogue models, raising questions about preparedness as AI systems increasingly demonstrate unexpected and potentially dangerous behavior.