Manu Ajith

rust

Writing Rust NIF code to convert encryption code from Elixir to Rust

In this article, we will go through what a NIF is, how to write safe NIF code using Rust and Rustler

elixir

Add latency tracking to phoenix live view apps.

Add latency tracking to phoenix live view apps

rust

Running scheduled cron jobs in Rust using tokio

Running periodic/scheduled tasks in Rust using tokio and async/await

rust

Making periodic http requests in Rust

Making http requests in Rust using reqwest, tokio, async/await and http proxies and cookies

nix

Configure max_connections for PostgreSQL using nix

How to configure max_connections value for PostgreSQL using nix

elixir

using elixir master branch using nix and nix-shell

There were some noteable changes that landed on the master branch in elixir today, related to improving the compilation, and I wanted to try out the latest version of elixir that was on the master branch. Since I use nix for setting up my projects, the latest version of elixir

elixir

Using variables inside binary pattern matching

I was refactoring a piece of code that I inherited in a codebase, which was parsing date from an external source in various formats into Date in elixir. The initial version of parse/1 function look something like the following: defmodule DateParser do def parse( <<_day_value::binary-size(

elixir

Tracing in Elixir/Erlang using :erlang.trace and GenServer

Recently, I wanted to trace a running Elixir system and see the messages that a function received. I was looking to inspect the params that it received and even manipulate the params to fiddle with some edge cases in the system. I knew that I could use dbg to start

postgresql

Deleting stale Postgres wal files

I was debugging a system earlier today, where one of the postgres instances ran out of disk space, and taking a closer look at the system, I realised that the backup command was failing silently, but the postgres archive files was still being retained in the wal folder. Checking a

postgresql

Finding long running SQL queries in PostgreSQL

Recently in one of the projects that I was working on, I came across a situation where the SQL query times was getting slower and slower per day, and I had to figure out what was happening to the system. One of the things that I checked immediately was whether

nix

Using custom/older versions of libraries and packages using nix.

Install custom or older versions of package(Ruby or Node or any other) using nix by overriding the package derivation using overrideAttrs

nix

nix-shell for elixir projects

Simple nix-shell to get started with using nix as development environment with Elixir/Phoenix/Rust

elixir

Tracing in Elixir/Erlang using dbg trips and tricks.

Tips and tricks for tracing in elixir/erlang using dbg module and some helper functions.

ruby

Custom types using dry-logic and predicates

Build custom types for IPv4 and IPv6 using dry-logic and predicates.

ghost

Upgrading ghost to 3.X from 2.x

Upgrading Ghost from v2.x to v3.x and fixing compatibility of ghost-cli with nodejs versions.

rails

Escaping special characters like & in rails Html views

Safely escape and render html characters while preserving special characters like ampersand(&) using strip_tags and Loofah

rails

Letter opener is not processing emails in rails app

letter_opener is one of the most useful gems out there for a rails developer. The configuration is pretty much easy and straightforward. But yet I stumbled upon a situation where it stopped working. All the setup instructions were in order, but still, for some reason, the emails were not

rspec

Fixing Rspec tests involving timestamps on CircleCI.

Use TimeCop gem or rspec be_within built in matcher to fix specs involving timestamps in CircleCI

AWS

Tuning concurrency settings for AWS S3 CLI

Tuning the max_concurrent_requests configuration for better performance when copying files from S3 buckets using the AWS CLI S3.

internet explorer

Using X-UA-Compatible to render websites in compatibility mode.

Add X-UA-Compatible meta tags or headers to force Internet Explorer to run websites in compatibility mode. the same can be done by forcing http headers on web servers

node

Fix for 100% CPU usage by node.js

If you are on MacOs and you don't have installed fsevents, you might see a spike in CPU usage when running projects which watches the filesystem changes, especially projects like Webpack. To fix the issue, install fsevents or rebuild using fsevents.

docker

Making dependent services wait till containers are healthy using docker health check

Using the health check option provided by docker we can make containers wait till the dependent containers are online and healthy

elixir

How to make a Genstage consumer subscribe only to particular events or stream

Genstage consumer can optionally subscribe to some of the events produced by the producer by using GenStage.BroadcastDispatcher as dispatcher and by specifying a :selector function which filters out the events we are interested in

linux

Extending the disk space on an EC2 instance

How to extend disk space on an AWS EC2 instance or Elastic BeanStalk instance by extending the Elastic Block Store volume and resizing the partition

blog

Upgrade ghost from v0.11 to v1.0+ and tweak Casper theme layout to use list instead of cards

How to update ghost from version v0.11 to v1.0 and up and tweaking the default casper theme for lists instead of cards, adding syntax highlighting, and bigger fonts