https://www.hillelwayne.com/tags/favorites/ Recent content in Favorites on Hillel Wayne Hugo -- gohugo.io en-us Wed, 20 Jan 2021 00:00:00 +0000 https://www.hillelwayne.com/post/we-are-not-special/ Wed, 20 Jan 2021 00:00:00 +0000 https://www.hillelwayne.com/post/we-are-not-special/ This is part two of the crossover project. Part one is here and part three is here. A conference talk based on this work is now available here. No one thinks about moving the starting or ending point of the bridge midway through construction. -Justin Cave I had to move a bridge. -Anonymous1 Carl worked as a mechanical verification engineer: he tested oil rigs to see how much they vibrated. https://www.hillelwayne.com/post/constructive/ Mon, 18 May 2020 00:00:00 +0000 https://www.hillelwayne.com/post/constructive/ Consider a data type that represents users, which includes “favorite people” and “blocked people”:1 data Person: favorites: set of Person blocked: set of Person We want a validation that says that these two sets are disjoint, a.k.a. no person can belong to both sets at once. We call these kinds of validations predicates, or boolean functions that correspond to our requirements. The predicates determine if a representable item is also a valid item. https://www.hillelwayne.com/post/this-is-how-science-happens/ Mon, 09 Mar 2020 00:00:00 +0000 https://www.hillelwayne.com/post/this-is-how-science-happens/ I love science. Not the “space is beautiful” faux-science, but the process of doing science. Hours spent calibrating equipment, cross-checking cites of cites of cites, tedious arguments about p-values and prediction intervals, all the stuff that makes science Go. And, when it does happen, the drama. I also want us to use more empirical science in software. That’s why I wrote a talk on it! One thing lay folk don’t realize is that science is social. https://www.hillelwayne.com/post/formally-modeling-migrations/ Wed, 09 Oct 2019 00:00:00 +0000 https://www.hillelwayne.com/post/formally-modeling-migrations/ Most of my formal methods examples deal with concurrency, because time is evil and I hate it. While FM is very effective for that, it gives people a limited sense of how flexible these tools are. One of the most common questions I get from people is Formal methods looks really useful for distributed systems, but I’m not making a distributed system. Is FM still useful for me? https://www.hillelwayne.com/post/why-dont-people-use-formal-methods/ Mon, 21 Jan 2019 00:00:00 +0000 https://www.hillelwayne.com/post/why-dont-people-use-formal-methods/ I saw this question on the Software Engineering Stack Exchange: What are the barriers that prevent widespread adoption of formal methods? The question was closed as opinion-based, and most of the answers were things like “its too expensive!!!” or “website isn’t airplane!!!” These are sorta kinda true but don’t explain very much. I wrote this to provide a larger historical picture of formal methods, why they’re actually so unused, and what we’re doing to make them used. https://www.hillelwayne.com/post/stamping-on-eventstream/ Wed, 02 Jan 2019 00:00:00 +0000 https://www.hillelwayne.com/post/stamping-on-eventstream/ The goal of a STAMP-based analysis is to determine why the events occurred… and to identify the changes that could prevent them and similar events in the future. 1 One of my big heroes is Nancy Leveson, who did a bunch of stuff like the Therac-25 investigation and debunking N-version programming. She studies what makes software unsafe and what we can do about that. More recently she’s advocated the “STAMP model” for understanding systems.