scootcho

GROKKING NOTES

I liked the way Grokking the coding interview organized problems into learnable patterns. However, the course is expensive and the majority of the time the problems are copy-pasted from leetcode. As the explanations on leetcode are usually just as good, the course really boils down to being a glorified curated list of leetcode problems.

So below I made a list of leetcode problems that are as close to grokking problems as possible.

Pattern: Sliding Window

• https://leetcode.com/problems/maximum-subarray/ # Close enough
• https://leetcode.com/problems/minimum-size-subarray-sum/

scootcho

Deploy your own PaaS!

Setting up Dokku with DigitalOcean and Namecheap

..or how I made my own heroku in a few hours for $3.98.

---

This write-up is very out of date! You probably shouldn't use it.

scootcho

How to develop with Jetpack locally with ngrok

To connect Jetpack in your local installation, you'll need a way for WP.com servers to reach your server. That can be done in a number of different ways:

• You can open your router's ports and use your public IP
• You can use some kind of Dynamic DNS provider.

But these options fall short of ngrok, which is a "localhost tunnel". It basically allows the Internet to hit a local port on your machine without worrying about ports or IPs.

As long as ngrok is running, Jetpack / WP.com will be able to communicate with your local site. This will allow remote modules like Site Search and Manage to work.

scootcho

#!/bin/bash

remote=origin ; for brname in `git branch -r | grep $remote | grep -v /master | grep -v /HEAD | awk '{gsub(/^[^\/]+\//,"",$1); print $1}'`; do git branch --track $brname $remote/$brname || true; done 2>/dev/null

scootcho

#!/bin/bash

# See https://github.com/docker-library/mongo/pull/63

docker run --rm --volumes-from my-mongo-server mongo unlink "/data/db/mongod.lock"
docker run --rm --volumes-from my-mongo-server mongo --repair

scootcho

Express & Postgres via Knex

Note: <example> is meant to denote text replaced by you (including brackets).

Setup

// global dependencies
npm install -g knex

scootcho

{"id":0,"name":"Bitcoin","owner":"0xc0F030eac8b588817f8dA16b9a2CDCcc6451B25c"}
{"id":1,"name":"Trump","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":2,"name":"King","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":3,"name":"Joe","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":4,"name":"china","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":5,"name":"usa","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":6,"name":"love","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":7,"name":"covid19","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":8,"name":"Obama","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}
{"id":9,"name":"buterin","owner":"0x874c44A007168b1f4B260Bc7017504D151b0aF7a"}

scootcho

Install Instructions

Install Hardhat

npm install --save-dev hardhat

Initiate a new Hardhat project (in empty directory)

npx hardhat

scootcho

tldr;
DDD is primarily about modeling a Ubiquitous (= überall vertreten) Language in an Bounded Context.
It avoids the design of monolithic applications.
Use DDD when the business model complexity is high (higher than the technical aspects of the project).

Bounded Context - semantic contextual boundary
Within the boundary, each component of the software model has a specific meaning and does specific things
The components inside a Bounded Context are context specific and semantically motivated.

In the Beginning of software modeling the Bounded Context is only coceptual and is part of the Problem Space.

scootcho

tldr;
DDD is primarily about modeling a Ubiquitous (= überall vertreten) Language in an Bounded Context.
It avoids the design of monolithic applications.
Use DDD when the business model complexity is high (higher than the technical aspects of the project).

Bounded Context - semantic contextual boundary
Within the boundary, each component of the software model has a specific meaning and does specific things
The components inside a Bounded Context are context specific and semantically motivated.

In the Beginning of software modeling the Bounded Context is only coceptual and is part of the Problem Space.