Alex Fallenstedt

Mp3 Player

2025-04-01T12:00:00-08:00

I remember being a kid with an iPod filled with music. It had music which I owned which I could listen to without an internet connection or using data from my phone plan. I missed that feeling and decided to build my own mp3 player as an Android app. I wanted to get more familiar with Kotlin, Android app development, and build something that could help people own their own data. The app is free, open source, and there are zero advertisements. You can download it here and start building your own music library…again.

Mocking http requests with Go

2023-12-21T12:36:41-08:00

I used to rely on dependency injection and interfaces to mock my http clients. This worked, but was very burdensome. I learned about the httptest package which provides utilities for HTTP testing. I’ll walk through an example test I made in my weather CLI

The code which makes a network request

I ping NOAA for a weather forecast using the following code. I have a FetchForecast method which invokes fetch to perform the network request at a specific URL.

Frig off chat gpt

2023-08-19T12:36:41-08:00

I like chatgpt, but I don’t like it crawling my site. That’s why I told ChatGPT to frig off.

These two lines will make that happen

User-agent: GPTBot
Disallow: /

You can check out an example on this site by visiting its robots.txt file.

More information about ChatGPT’s crawler can be found here

Recording Web Vitals with New Relic

2023-08-06T12:36:41-08:00

How do you measure the performance and user experience of your website? Every change made can affect page loading speed, interactivity and visual stability. Together, these contribute to your product’s performance, search engine ranking, and advertisement performance. With New Relic, you can monitor these web vitals and be notified of user experience regressions.

Which main web vitals I should monitor?

From Google, their are several main web vitals you should focus on monitoring to evaluate how well users are experiencing your application.

Managing API Gateway Deployments with Terraform: Achieving Full Stage Isolation

2023-02-20T12:36:41-08:00

The Problem

API Gateway allows you to assocate deployments with stages, each stage representing a logical reference of your api. For example, my gardentour API project needs a dev and a prod stage to represent my environments.

I manage infrastructure with terraform, and I needed to achieve full isolation of my stages. It would be impracticable to manage deploys of many API Gateway stages with a single Terraform environment like so:

How I built a Powerbox

2023-01-19T12:36:41-08:00

I recently had a power outage which lasted 10 hours here at home. It was not pleasant sitting the dark with just a flashlight. I knew I had to build a power box, a device which provides a variety of input leads from a battery. This article details what how I designed and built a power box for simple applications such as powering lamps, charging phones, laptops, and powering my ham radio.

Terraform Cognito With Lambda Triggers

2022-07-18T12:36:41-08:00

The Problem

I have been building a side project with AWS Cognito and Terraform. I wanted a custom message lambda trigger to be invoked anytime the user signed up for my app, however I kept getting permission errors. This blog shows you the terraform configuration you need to to let cognito invoke lambda triggers with Terrafrom.

Terraform config

AWC Cognito

For AWS Cognito, I have a simple user pool that allows users to sign up with their email and a passowrd, and a single user pool client to hold users for my development environment.

Streaming Tweets With Go

2021-12-29T12:36:41-08:00

Update

This repo is read-only and is no longer worked on. Twitter was a wonderful platform, built by a wonderful team. With its recent changes, its time to re-evaluate what we invest in and the world we want to build. To the projects using this library, I’ll leave the repo read-only so you can migrate on your own time

Building with free APIs is a great way to teach yourself new skills in languages you like. I’ve always found APIs as an underrated way to learn something new. Building with APIs brings challenges that force you to learn new parts of programming that video tutorials can not do.

Three Steps I Took to Get a Job Offer From Amazon

2021-07-12T12:36:41-08:00

Last year, I took the plunge and applied for a Frontend Engineering Position at Amazon. I knew little about the interview process and I had just one month to prepare for it. The result? I got an offer. In fact, the use of the interview techniques below granted me the opportunity to choose between two competing job offers. In this guide I will reveal the steps I took in order to become a competitive candidate.

Using Rust and WebAssembly to Process Pixels from a Video Feed

2021-05-10T12:36:41-08:00

At Streem we are on a mission to make the world’s expertise more accessible. We create guidance tools to steer the discussion and ensure accurate understanding the first time. One of the guidance tools we are developing for web is a 3d cursor that can be positioned in a remote video. To accomplish this, we need to process a lot of raw pixel data and AR data per frame.