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Master Elixir.

Elixir mastery exercises. Become your team's resident Elixir expert.

Elixir

Build your own Redis

FREE THIS MONTH

Build your own Redis

Discover concurrent programming in Elixir while also learning about TCP servers, network programming, and the Redis Protocol.

Respond to PING

Respond to multiple PINGs

Handle concurrent clients

Implement the ECHO command

Implement the SET & GET commands

RDB Persistence

RDB file config

Read a string value

Read multiple keys

Read multiple string values

Read value with expiry

Replication

Configure listening port

The INFO command

The INFO command on a replica

Initial Replication ID and Offset

Send handshake (1/3)

Send handshake (2/3)

Send handshake (3/3)

Receive handshake (1/2)

Receive handshake (2/2)

Empty RDB Transfer

Single-replica propagation

Multi Replica Command Propagation

Command Processing

ACKs with no commands

ACKs with commands

WAIT with no replicas

WAIT with no commands

WAIT with multiple commands

Streams

The TYPE command

Create a stream

Validating entry IDs

Partially auto-generated IDs

Fully auto-generated IDs

Query entries from stream

Query single stream using XREAD

Query multiple streams using XREAD

Blocking reads without timeout

Blocking reads using $

Transactions

The INCR command (1/3)

The INCR command (2/3)

The INCR command (3/3)

The MULTI command

The EXEC command

Empty transaction

Queueing commands

Executing a transaction

The DISCARD command

Failures within transactions

Multiple transactions

Build your own HTTP server

Build your own HTTP server

HTTP is the protocol that powers the web. In this challenge, you'll build a HTTP server that's capable of handling simple GET/POST requests, serving files and handling multiple concurrent connections.

Along the way, we'll learn about TCP connections, HTTP headers, HTTP verbs, handling multiple connections and more.

Respond with 200

Extract URL path

Respond with body

Concurrent connections

Read request body

HTTP Compression

Compression headers

Multiple compression schemes

Gzip compression

Build your own BitTorrent

Build your own BitTorrent

Learn about .torrent files and the famous BitTorrent protocol. Implement your own BitTorrent client in Elixir.

Decode bencoded strings

Decode bencoded integers

Decode bencoded lists

Decode bencoded dictionaries

Parse torrent file

Calculate info hash

Download a piece

Download the whole file

Magnet Links

Parse magnet link

Announce extension support

Send extension handshake

Receive extension handshake

Request metadata

Receive metadata

Download a piece

Download the whole file

Many more to come...

coming soon

We release new challenges based on user votes. Let us know what you'd like to see next!

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RECENT ACTIVITY 0

“ The Redis challenge was extremely fun. I ended up having to read the Redis Protocol specification doc pretty carefully in its entirety! The result felt like lightly-guided independent study, if that makes sense. (Which, again, was lots of fun)

Charles Guo Software Engineer, Stripe “ I think the instant feedback right there in the git push is really cool. Didn't even know that was possible!

Patrick Burris Senior Software Developer, CenturyLink