protohackers

Solutions to the Protohackers server programming challenges:

0. Smoke Test - Echo service from RFC 862 (TCP).
1. Prime Time - Primality testing service using a JSON-based response-request protocol (TCP).
2. Means to an End - Asset price tracking service using a binary message format (TCP).
3. Budget Chat - Simple chat room (TCP).
4. Unusual Database Program - Key-value store (UDP).
5. Mob in the Middle - Man-in-the-middle attack on Budget Chat (TCP).

Setup

$ mkdir -p bin
$ go build -o bin ./...

Deployment

The server is deployed/hosted on AWS: see the CloudFormation template. Additionally, a useful collection of tiny Bash scripts is defined in internal/deploy.

I typically use direnv to automatically set project-relevant environment variables and add helper utilities to PATH. My .envrc looks something like:

export AWS_ACCESS_KEY_ID=
export AWS_SECRET_ACCESS_KEY=
export AWS_DEFAULT_REGION=

export EC2_KEYNAME=
export CHECKER_ADDR=

PATH_add internal/deploy
PATH_add bin