Oct 7

How a few lines of code reduced database load by a few million queries

Back when I originally published Slonik PostgreSQL client for Node.js, I was working with large datasets, inserting tens of millions of records per hour. However, the shape of the data being inserted was usually pretty flat and therefore pretty easy to insert using INSERT INTO ... SELECT * FROM unnset()…

Database

3 min read

Database

3 min read

Oct 6

Load-balancing PostgreSQL queries between read-only and read-write instances

Scaling databases is hard. However, perhaps the lowest hanging fruit is introducing read-only replicas. A typical load balancing requirement is to route all “logical” read-only queries to a read-only instance. This requirement can be implemented in 2 ways: Create two database clients (read-write and read-only) and pass them around the…

Postgres

4 min read

Postgres

4 min read

Sep 30

Building advanced SQL search from a user text input

We are going to build a program that parses user search query and serializes it into a SQL statement. Here is an example of a search query: firstName:"Thomas" -jefferson birthdate:[1960 TO 1970] (profession:"inventor" OR profession:"engineer") What this says is: Find records with first name “Thomas” Exclude mentions of “jefferson” Narrow down results to where the birthdate is between 1960 and 1970

Java Script

1 min read

Building advanced SQL search from a user text input

Java Script

1 min read

Building advanced SQL search from a user text input

We are going to build a program that parses user search query and serializes it into a SQL statement. Here is an example of a search query:

firstName:"Thomas" -jefferson birthdate:[1960 TO 1970] (profession:"inventor" OR profession:"engineer")

What this says is:

Find records with first name “Thomas”
Exclude mentions of “jefferson”
Narrow down results to where the birthdate is between 1960 and 1970
Narrow down results to where the profession is either “inventor” or “engineer”

In SQL, this could look something like:

"firstName" = 'Thomas' AND
"searchName" ILIKE '%jefferson%' AND
"birthdate" BETWEEN 1960 AND 1970 AND
(
  "profession" = 'inventor' OR
  "profession" = 'engineer'
)

It might not be the most succinct form of SQL to do the job, but it is good enough.

https://contra.com/p/WobOBob7-building-advanced-sql-search-from-a-user-text-input

Sep 11

Fully qualified names vs a jungle of imports

Originally published on Contra Open any Node.js project and any deeply nested file within that project and the first thing you will see is a variation of: import { configureScope } from '@sentry/node'; import { serializeError } from 'serialize-error'; import { type CommonQueryMethods, sql } from 'slonik'; import { z } from 'zod'; import…

Nodejs

3 min read

Fully qualified names vs a jungle of imports

Nodejs

3 min read

Sep 7

Migrating from Cypress to Playwright using GPT3

Cypress and @playwright/test are two competing integration testing frameworks. We have been using Cypress for a long time but recently made a decision to migrate our Cypress tests to Playwright, all 400 of them. It is absolutely worth it for the speed and reliability gains (a future post)… However, it meant a lot of manual work! Or so I thought… Continue reading on Contra https://contra.com/p/PWBcPYZc-rewriting-tests-from-cypress-to-playwright-using-gpt-3

Playwright Test

1 min read

Migrating from Cypress to Playwright using GPT3

Playwright Test

1 min read

Migrating from Cypress to Playwright using GPT3

Left: Cypress, Right: Playwright. There are a lot of structural similarities between how both tests are written.

Continue reading on Contra

https://contra.com/p/PWBcPYZc-rewriting-tests-from-cypress-to-playwright-using-gpt-3

Aug 5

Validating PostgreSQL results & inferring query static types

Most of the bugs come from misaligned expectations. When working with databases, the first line of defense is to type the expected query results statically. type SubscriptionPayment = { id: number, subscriber: string, amount: number }; await connection.many( sql<Person>` SELECT id, subscriber, amount FROM subscription_payment ` ); Doing this already…

Nodejs

4 min read

Validating PostgreSQL results & inferring query static types

Nodejs

4 min read

Jun 27

What makes a good commit

First, the main goal of a commit is to introduce an atomic change. Atomic changes contain only one feature, refactor, fix, etc. A good commit allows to evaluate one change at a time and it contains only/all the changes necessary. Bad commits happen because of a bad workflow. Your workflow…

Git

3 min read

Git

3 min read

Aug 10, 2021

CTO vs Head of Engineering

What is the difference between CTO and Head of Engineering / VP of Technology at a 30–100 people company? — Contra is growing fast and we are bringing in people that are taking over some of the responsibilities that were owned by the CEO/CTO at the early stages of the company. For CEO, that’s noticeable with Head of Product. For CTO, that’s most likely to be Head of Engineering. However…

Technology

4 min read

Technology

4 min read

Oct 26, 2020

Redesigning Remote Team Culture

As the world becomes “virtual first”, businesses need to step up their company culture game beyond motivational posters in the office. — Originally published by Tracy Chen on Snack Blog. The pandemic accelerated the shift to a fully-remote or hybrid workforce, and companies had to quickly adopt new collaboration tech and processes to enable employees to work from home. Similarly, transitioning to a remote work culture requires intention and effort, and businesses…

Remote Working

3 min read

Remote Working

3 min read

Sep 25, 2020

How I got my first Node.js job

A story of shameless persistence to inspire those who are seeking their first job in IT. — It was 2012. I was in a university. I was obsessed with building games. The moment I read about Node.js, I thought of it as the future of online gaming. I began studying Node.js documentation. The goal was to learn the basics and find a freelancing project to work on…

Careers

2 min read