The author describes creating a DNS sinkhole using an ESP32 microcontroller to combat doomscrolling. By intercepting DNS requests on their local network and redirecting specific domains (like social media sites) to a local web server, they effectively block access to these sites. The ESP32 runs a custom DNS server that returns a pre-defined IP address for targeted domains, leading devices to a blank webpage hosted on the ESP32 itself. This allows the author to curtail time spent on distracting websites without relying on browser extensions or more complex network configurations.
mdq is a command-line tool, inspired by jq, that allows users to process and manipulate Markdown files using CSS-like selectors. It can extract specific elements from Markdown, such as headings, paragraphs, or code blocks, and output them in various formats, including Markdown, HTML, and text. This facilitates tasks like extracting specific sections of a document, reformatting content, and generating summaries, offering a powerful way to automate Markdown workflows.
Hacker News users generally praised mdq for its potential usefulness, comparing it favorably to jq for JSON. Several commenters expressed interest in using it for tasks like extracting links or reformatting Markdown files. Some suggested improvements, such as adding support for YAML frontmatter and improving error handling. Others highlighted the complexities of parsing Markdown reliably due to its flexible nature and the potential challenges of handling variations and edge cases. One user pointed out the limitations of existing markdown parsers and the difficulties in accurately representing markdown as a data structure, while another cautioned against over-engineering the tool for simple tasks that could be accomplished with grep, sed, or awk.
This paper presents a simplified derivation of the Kalman filter, focusing on intuitive understanding. It begins by establishing the goal: to estimate the state of a system based on noisy measurements. The core idea is to combine two pieces of information: a prediction of the state based on a model of the system's dynamics, and a measurement of the state. These are weighted based on their respective uncertainties (covariances). The Kalman filter elegantly calculates the optimal blend, minimizing the variance of the resulting estimate. It does this recursively, updating the state estimate and its uncertainty with each new measurement, making it ideal for real-time applications. The paper derives the key Kalman filter equations step-by-step, emphasizing the underlying logic and avoiding complex matrix manipulations.
HN users generally praised the linked paper for its clear and intuitive explanation of the Kalman filter. Several commenters highlighted the value of the paper's geometric approach and its focus on the underlying principles, making it easier to grasp than other resources. One user pointed out a potential typo in the noise variance notation. Another appreciated the connection made to recursive least squares, providing further context and understanding. Overall, the comments reflect a positive reception of the paper as a valuable resource for learning about Kalman filters.
TheretoWhere.com lets you visualize ideal housing locations in a city based on your personalized criteria. By inputting preferences like price range, commute time, proximity to amenities (parks, groceries, etc.), and preferred neighborhood vibes, the site generates a heatmap highlighting areas that best match your needs. This allows users to quickly identify promising neighborhoods and explore potential living areas based on their individualized priorities, making the often daunting process of apartment hunting or relocation more efficient and targeted.
HN users generally found the "theretowhere" website concept interesting, but criticized its execution. Several commenters pointed out the limited and US-centric data, making it less useful for those outside major American cities. The reliance on Zillow data was also questioned, with some noting Zillow's known inaccuracies and biases. Others criticized the UI/UX, citing slow load times and a cumbersome interface. Despite the flaws, some saw potential in the idea, suggesting improvements like incorporating more data sources, expanding geographic coverage, and allowing users to adjust weighting for different preferences. A few commenters questioned the overall utility of the heatmap approach, arguing that it oversimplifies a complex decision-making process.
Summary of Comments ( 9 )
https://news.ycombinator.com/item?id=43204091
Hacker News users generally praised the project's simplicity and effectiveness for blocking distracting websites. Several commenters suggested improvements, such as using a pre-built DNS sinkhole list or implementing a local DNS server for better performance. Some discussed the ethics and potential downsides of blocking websites, particularly for families or in situations where access is necessary. Others offered alternative solutions, like using Pi-hole or modifying the hosts file. A few pointed out potential issues with the ESP32's limited resources and the importance of using a reliable power supply. The overall sentiment was positive, viewing the project as a clever, albeit somewhat limited, solution to a common problem.
The Hacker News post "Turning my ESP32 into a DNS sinkhole to fight doomscrolling" generated a moderate number of comments, mostly focusing on the practicality and efficacy of the approach, as well as alternative solutions.
Several commenters questioned the effectiveness of using an ESP32 for this purpose, citing its limited resources and potential performance bottlenecks. One commenter pointed out that DNS queries are generally small and infrequent, suggesting the ESP32 might be sufficient for a home network. Another countered this by highlighting the ESP32's relatively slow processing speed and limited RAM, which could become problematic with more devices or complex DNS configurations. The potential for latency issues and single point of failure were also raised as concerns.
A prominent thread discussed alternative methods for achieving the same goal, such as using a Pi-hole, modifying the hosts file, or utilizing features built into existing routers. Pi-hole was frequently mentioned as a more robust and feature-rich solution, already designed for network-wide ad blocking and DNS sinkholing. Modifying the hosts file was suggested as a simpler, though potentially less manageable, alternative for individual devices. Some commenters highlighted the built-in DNS filtering options available in certain routers, offering a convenient solution without requiring additional hardware.
Some users discussed the broader implications of DNS sinkholing, including the ethical considerations of blocking content and the potential for inadvertently breaking legitimate websites. One commenter argued that while the author's intentions were understandable, blocking entire domains might be overly aggressive, suggesting a more targeted approach to filtering specific unwanted content.
While generally receptive to the author's ingenuity, the overall sentiment in the comments leans towards exploring alternative, more established solutions for DNS sinkholing and content filtering. The ESP32 approach is acknowledged as a functional proof-of-concept, but its limitations and potential drawbacks are highlighted, leading to recommendations for more robust and scalable alternatives. The discussion also extends to the ethical considerations surrounding content blocking and the importance of carefully considering the implications of such practices.