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Master Haskell.

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

Build your own Redis
FREE THIS MONTH
This challenge is free until 1 June 2024!
Build your own Redis

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

Bind to a port
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Respond to PING
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Respond to multiple PINGs
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Handle concurrent clients
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Implement the ECHO command
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Implement the SET & GET commands
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Expiry
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Replication

Configure listening port
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The INFO command
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The INFO command on a replica
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Initial Replication ID and Offset
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Send handshake (1/3)
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Send handshake (2/3)
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Send handshake (3/3)
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Receive handshake (1/2)
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Receive handshake (2/2)
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Empty RDB Transfer
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Single-replica propagation
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Multi Replica Command Propagation
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Command Processing
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ACKs with no commands
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ACKs with commands
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WAIT with no replicas
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WAIT with no commands
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WAIT with multiple commands
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RDB Persistence

RDB file config
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Read a key
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Read a string value
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Read multiple keys
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Read multiple string values
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Read value with expiry
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Streams

The TYPE command
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Create a stream
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Validating entry IDs
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Partially auto-generated IDs
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Fully auto-generated IDs
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Query entries from stream
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Query with -
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Query with +
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Query single stream using XREAD
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Query multiple streams using XREAD
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Blocking reads
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Blocking reads without timeout
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Blocking reads using $
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Build your own HTTP server
FREE THIS MONTH
This challenge is free until 1 June 2024!
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.

Bind to a port
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Respond with 200
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Extract URL path
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Respond with body
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Read header
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Concurrent connections
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Get a file
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Post a file
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HTTP Compression

Content-Encoding header
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Multiple compression schemes
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Gzip compression
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Build your own BitTorrent
Build your own BitTorrent

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

Decode bencoded strings
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Decode bencoded integers
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Decode bencoded lists
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Decode bencoded dictionaries
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Parse torrent file
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Calculate info hash
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Piece hashes
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Discover peers
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Peer handshake
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Download a piece
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Download the whole file
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Build your own grep
Build your own grep

Learn about regular expressions and how they're evaluated. Implement your own version of grep in Haskell.

Match a literal character
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Match digits
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Match alphanumeric characters
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Positive Character Groups
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Negative Character Groups
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Combining Character Classes
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Start of string anchor
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End of string anchor
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Match one or more times
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Match zero or one times
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Wildcard
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Alternation
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Backreferences

Single Backreference
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Multiple Backreferences
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Nested Backreferences
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Many more to come...
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