How to Create Constant Maps, Slices, & Arrays in Golang

Oct 21, 2019 by Lane Wagner

For the most part, I’ve found that Go developers are pretty good at using global constants for configuration rather than global variables. However, a problem arises when we want a constant version of some of the more complex types. The Go compiler does not allow us to create array, map, or slice constants. After realizing this, many developers decide to use a dangerous global variable. In this article, we will explore some alternative options to effectively make constant maps, slices, and arrays, albeit with some trade-offs.

Systems and Processes that Aren’t in Code are Terrifying

Oct 03, 2019 by Lane Wagner

My worst enemy is processes that a developer spun up years ago on a server everyone has forgotten about. I don’t know how to find these systems reliably, I don’t know where they came from, what depends on them, and if they are safe to delete. For example, the dreaded 15 6 2 1 * /home/lane/backup.sh. You may recognize this as a Unix cronjob, a job that is scheduled to run on a server periodically.

The Proper Use of Pointers in Go (Golang)

Sep 25, 2019 by Lane Wagner

Go has become increasingly popular in recent years, especially in my local area. It has been consistently displacing other backend languages like Ruby, Python, C# and Java. Go is wanted for its simplicity, explicitness, speed, and low memory consumption. Many developers that are new to the language, or new to a language that can handle memory directly using pointers end up misusing those pointers. What Is a Pointer? A pointer is a variable that stores the address of a value, rather than the value itself.

How to Recursively Traverse JSON Objects

Sep 22, 2019 by Lane Wagner

I’ve found that it’s pretty rare that I need recursion in application code, but every once in a while I need to write a function that operates on a tree of unknown depth, such as a JSON object, and that’s often best solved recursively. Even though recursion is rare, it is important to recognize when a problem is best solved recursively so that we can implement a good solution when the time comes.

How to Secure Your Bitcoin

Aug 30, 2019 by Lane Wagner

If you’re new to Bitcoin and cryptocurrency, you may have heard the common phrase not your keys not your coins. While self-custody isn’t for everyone, its the only way to truly have exclusive control over your funds. If that’s what you’re into, read on. Dangers of storing your own Bitcoin In order to spend your Bitcoin, you need to have access to your wallet or to the seed phrase that was created alongside the wallet.

Security in Dependencies

Aug 21, 2019 by Lane Wagner

Choosing the right dependencies is a difficult task. Assuming the developer of an application is the best programmer in the world, the “best” thing to do would be to write the entire codebase alone. This would eliminate the bugs, vulnerabilities, and malicious intrusions of inferior developers. The trouble is that we like to move quickly in order to be able to compete in the market and offer new features. We try to avoid re-inventing the wheel when the wheel in question is widely used, is peer-reviewed, and we consider it stable and trusted.

Encoding vs Encryption - They Aren’t the Same

Aug 14, 2019 by Lane Wagner

While encryption does involve various methods of encoding data, the two are absolutely not interchangeable. In fact, if you get them mixed up it can result in serious data breaches and security vulnerabilities. Encryption is a specific subset of encoding where the encoded messages can only be accessed by authorized parties (the ones holding the decryption keys). Encoding is simply a way of representing data in a specific format. For example, raw binary data can be encoded and decoded using the ASCII format as shown in the table below.

Automatic Cross-Platform Deployments with Electron on a CI Server (Travis)

Aug 08, 2019 by Lane Wagner

This is a tutorial on how to set up an Electron app on Travis CI, so that new versions are deployed to Github Releases with a simple pull request. Boilerplate I created a boilerplate repo that has all the necessary configuration to deploy a minimalistic app to Github releases. If you get lost during the tutorial you can look to that as an example. Also, if you don’t have an electron app yet and just want to start with it as an example feel free.

Creating and Remembering a Strong Passphrase

Aug 03, 2019 by Lane Wagner

We all have hundreds of online accounts. Ideally, as many of those accounts as possible have unique passwords. Unique passwords however present a difficult problem. No one can remember hundreds of strong passwords. To fix this problem, we created password managers. Now, all of our passwords are neatly stored in one place, encrypted by one master password or passphrase. The problem with this of course is the master password or passphrase needs to be very secure.

BIP 32 Watch-Only Wallets

Jul 25, 2019 by Lane Wagner

Bitcoin improvement proposal 32 is, in my opinion, one of the most important BIPs we have. (Thanks Peter Wuille!) BIP 32 gave us Hierarchical Deterministic Wallets. That is, the ability to create a tree of keys from a single seed. In the early days of Bitcoin, each time a user wanted to receive new coins, their wallet would randomly generate a new Bitcoin private key, along with the associated public key and address.