April 25, 2021

Learning about p-value

What do people want you to think whey they say “p-value”? The top hit from Google says: The p value is the evidence against a null hypothesis. The smaller the p-value, the stronger the evidence that you should reject the null hypothesis. P values are expressed as decimals although it may be easier to understand what they are if you convert them to a percentage. For example, a p value of 0.

April 18, 2021

Posts Of The Week 2021-04-15

Lots of small things today. History “Those who cannot remember the past are condemned to repeat it”. I love reading about how software came to be the way they are today. Before we can talk about where generics are going, we first have to talk about where they are, and how they got there. https://cr.openjdk.java.net/~briangoetz/erasure.html Go Errors Error handling is still jacked in Go 1.16. That is, the formatting change is still not present.

April 3, 2021

Workflow Orchestration - Part 3 (How do I use this?)

In this part of the series, we’ll write some hands-on Temporal code and run it. Let’s start with our requirements: You need to transmit a data packet. You can choose from multiple Route Providers to do this. Transmission takes time – you will be notified on a callback URL when the packet is delivered. Delivery may fail – either because the acknowledgement was not sent or arrived late (because Internet).

April 1, 2021

Posts Of The Week 2021-04-01

I spent a couple of hours evaluating 3rd party libraries. What have I learned? For me, there’s one clear winner in a small field of candidates. Presently, these are the top hits for “golang gauge counter timer”. https://pkg.go.dev/github.com/go-kit/kit/metrics https://pkg.go.dev/github.com/facebookgo/metrics https://github.com/uber-go/tally The first result is go-kit. Go-kit isn’t a metrics library. Rather, it bills itself as a “framework for building microservices.” Its metrics package is simply a set of interfaces.

March 24, 2021

Posts Of The Week 2021-03-25

Go does not allow cyclic imports. A solution is to create a “shared” package to hold interfaces that related packages all reference. This, for some reason, reminds of me join tables in SQL. Here is an example of a typical Go project. Packages toward the bottom, e.g., “common/persistence”, allow different packages to work with each other without introducing cyclic dependencies. For this project, “log” can be referenced by “config”, but cannot use “config” to conifgure itself.

March 8, 2021

Posts Of The Week 2021-03-11

Oldie but goodie. Go concurrency patterns https://drive.google.com/file/d/1nPdvhB0PutEJzdCq5ms6UI58dp50fcAN/view

March 7, 2021

Workflow Orchestration - Part 2 (Why do I care?)

An increasingly distributed and fragile world Workflow platforms are important because software engineers are increasingly adopting distributed systems in their architecture. There are two reasons for this change: 1) Users are demanding more frequent releases, feature teams, better peformance, and higher availability; 2) Providers are increasingly moving away from “use our library” (Spring Framework) to “use our APIs” (AWS, Azure, and GCP). This change is undoubtedly a good thing, however, it also introduces new problems.

March 7, 2021

Posts Of The Week 2021-03-04

Two book recommendations https://www.oreilly.com/library/view/designing-data-intensive-applications/9781491903063/ https://www.oreilly.com/library/view/making-software/9780596808310/ Designing Data Intensive Applications: Don’t let the name fool you. The knowledge in this book applies to more than just data processing applications but to distributed systems in general. It is a great book for all software architects. Making Software: What Really Works, and Why We Believe It: A meta-analysis of various theories on software development processes. Is TDD effective? Is Agile just a hype or is it just misused?

February 28, 2021

Workflow Orchestration 1 - What is a workflow?

Introduction It is hard to describe what a Workflow Platform is. It is both familiar and exotic. There are aspects of the problem space we all know well: Retries, eventual consistency, message processing semantics, visibility, heartbeating, and distributed processing to name a few. Yet, when they’re all put together in a pretty package with a bow tied on top, it becomes something almost magical. It feels like seeing the iPhone for the first time: Of course you want a touch screen on a cellphone and mobile internet access.

February 22, 2021

Posts Of The Week 2021-02-18

The Peseverance rover lands on Mars. In this month, the UAE, PRC, and US all sent scientific instruments to Mars. https://www.nytimes.com/2021/02/18/science/nasa-peseverance-mars-landing.html