My highly opinionated list of things needed to build an app in Scala

README.md

Libraries

• Web Server: Play (framework) or http4s (library)
• Actors: akka
• Asynchronous Programming: monix (for tasks, reactors, observables, scheduler etc)
• Authentication: Silhouette
• Authorization: Deadbolt
• Command-line option parsing: case-app
• CSV Parsing: kantan.csv
• DB: doobie (for PostgreSQL)
• Evolutions: flyaway
• I/O: better-files
• JSON: circe + rapture-json (for dynamic JSON access)
• Enums: enumeratum
• Records: scala-records
• DI: macwire
• Config: PureConfig
• Logging: log4s for Java logging or else scribe or BlindSight
• RPC: finagle
• Caching: scalacache
• Templating: ssp
• Utils: pimpathon, scalactic, rapture, shapeless
• Algebra: cats + monocole
• Numeric: spire, squants
• Codecs: scodec
• Java Integration: scala-time, scala-java8-compat
• Data Validation: accord, refined
• Streams: scalaz-zio
• ScalaJS: scalajs-react + Components

If you are using Play, these are reasonable alternatives to above since these have better out-of-the-box Play support:

• ORM: slick + slick-pg + type-checked SQL (for PostgreSQL)
• Evolutions: play-evolutions
• JSON: play-json + play-json-derived + support for >22 fields
• Logging: play-logger
• Templating: twirl
• ScalaJs + Play

Code Quality

• Testing: ScalaTest + ScalaCheck
• Coverage: https://codecov.io + scoverage
• CI: CircleCI
• Lint: wartremover, linter, etc
• Code style: ScalaStyle
• Codacy: https://www.codacy.com/
• Error Monitoring: OverOps + Loggly + NewRelic

sbt plugins

• Sample multi-project build.sbt
• Trailing commas
• better-monadic-for
• native packager + sbt-docker
• sbt-updates

See also: https://github.com/lauris/awesome-scala

@mdedetrich - Yes, quill is cool but I prefer writing vanilla SQL because:

1. I can copy paste the SQL from my Scala code into my DB console or into other parts of my company's codebase which maybe written in Python or Java.
2. What if I need to use something not in the ORM (e.g. some PostgreSQL features like CAST or functions)?

I still want static checking of my vanilla SQL queries so I use this

@yawaramin, @mdedetrich, @denisftw - Thanks for the suggestions. I added scalacache, log4s, monix

@rtfpessoa: What are the benefits of sbt-coursirer besides faster downloads? I personally don't care about my download speed because I have pretty good internet and most of my jars are in my ivy cache anyway.

@wsargent - I am yet to find something regarding authorization and authentication that I like - I always have to do something custom so far. I will give Silhouette and Deadbolt one more try :)

A nitpick: none of doobie, slick or quill is an ORM and they emphasize not being ORMs actually. How about just DB?

For configuration, there is a new project which seems very good if you are in the "toward pure software" mood: https://cir.is/
From the site:

Lightweight, extensible, and validated configuration loading in Scala and Scala.js.
The core library is dependency-free, while modules provide library integrations.
"Ciris encourages compile-time safety by defining as much as possible of your configurations in Scala"

Documentation seems to be quite good, to!

And if you spend a lot of time and boilerplate copying things between case class, there is that little lib built on top of shapeless: https://github.com/scalalandio/chimney

Saw Play, stopped reading