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Master Dart.

Dart

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

205 exercises

Dart

Dart Challenges

Put your Dart skills to the test. Practice by building popular open-source tools from scratch.

Build your own Shell

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Build your own Shell

A shell is the program that interprets what you type into the terminal. It reads your commands, runs programs, and prints their output. Popular examples are Bash and ZSH.

In this challenge, you'll build your own shell from scratch.

Your shell will run a REPL, parse commands, spawn processes, and more.

Handle invalid commands

Implement a REPL

Locate executable files

Navigation

The pwd builtin

The cd builtin: Absolute paths

The cd builtin: Relative paths

The cd builtin: Home directory

Quoting

Backslash outside quotes

Backslash within single quotes

Backslash within double quotes

Executing a quoted executable

Redirection

Redirect stdout

Redirect stderr

Command Completion

Builtin completion

Completion with arguments

Missing completions

Executable completion

Multiple completions

Partial completions

Filename Completion

File completion

Nested file completion

Directory completion

Missing completions

Multiple matches

Partial completions

Multi-argument completions

Programmable Completion

Register complete builtin

Printing missing specifications

Displaying registered specifications

Single completion

Handling no completions

Passing command-line arguments

Passing environment variables

Multiple completer candidates

Longest common prefix

Unregister a completion

Background Jobs

The jobs builtin

Starting background jobs

Printing background job output

List a single job

List multiple jobs

Reap multiple jobs

Reap before the next prompt

Recycle job numbers

Pipelines

Dual-command pipeline

Pipelines with built-ins

Multi-command pipelines

History

The history builtin

Listing history

Limiting history entries

Up-arrow navigation

Down-arrow navigation

Executing commands from history

History Persistence

Read history from file

Write history to file

Append history to file

Read history on startup

Write history on exit

Append history on exit

Parameter Expansion

The declare builtin

Printing missing variables

Storing shell variables

Validating variable names

Expanding variables

Expansion with braces

Expanding empty variables

Build your own Redis

Build your own Redis

Discover concurrent programming in Dart 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

Lists

Append an element

Append multiple elements

List elements (positive indexes)

List elements (negative indexes)

Prepend elements

Query list length

Remove an element

Remove multiple elements

Blocking retrieval

Blocking retrieval with timeout

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

Optimistic Locking

The WATCH command

WATCH inside transaction

Tracking key modifications

Watching multiple keys

Watching missing keys

The UNWATCH command

Unwatch on EXEC

Unwatch on DISCARD

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 propagation

Command processing

ACKs with no commands

ACKs with commands

WAIT with no replicas

WAIT with no commands

WAIT with multiple commands

RDB Persistence

RDB file config

Read a string value

Read multiple keys

Read multiple string values

Read value with expiry

AOF Persistence

Default AOF options

AOF options from flags

Create append-only directory

Create append-only file

Create manifest file

Write a single command

Write multiple commands

Filter write commands

Replay a single command

Replay multiple commands

Pub/Sub

Subscribe to a channel

Subscribe to multiple channels

Enter subscribed mode

PING in subscribed mode

Publish a message

Deliver messages

Sorted Sets

Create a sorted set

Retrieve member rank

List sorted set members

ZRANGE with negative indexes

Count sorted set members

Retrieve member score

Remove a member

Geospatial Commands

Respond to GEOADD

Validate coordinates

Store a location

Calculate location score

Respond to GEOPOS

Decode coordinates

Calculate distance

Search within radius

Authentication

Respond to ACL WHOAMI

Respond to ACL GETUSER

The nopass flag

The passwords property

Setting default user password

The AUTH command

Enforce authentication

Authenticate using AUTH

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 from scratch using TCP primitives. Your server will be 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

Persistent Connections

Persistent connections

Concurrent persistent connections

Connection closure

Dart LEADERBOARD

“ There are few sites I like as much that have a step by step guide. The real-time feedback is so good, it's creepy!

Ananthalakshmi Sankar Automation Engineer at Apple “ 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