Is Lamdera for me?
Lots of tech projects seem to promote fast adoption and getting started, but not appropriateness, pitfalls or caveats.
Here are some reasons Lamdera might not be for you today. Things change though!
That said, as they say; “no risk, no reward”!
What is Lamdera?
Lamdera is a type-safe full-stack web-app platform for Elm.
Lamdera's goal is to empower you to write only the code that matters for the application logic of what you're building; not by hiding complexity, but by removing it.
Hosting, deployments, migrations, networking and persistent storage are handled by Lamdera, so you can focus on your application logic, not glue code.
See the Lamdera overview for more.
Reasons to not use Lamdera
You really don't like Elm
All user code in Lamdera is written in Elm, a delightful language for reliable web apps. Elm's design allows for certain Lamdera features, like type-safe live-reload deployments, that would be impossible with other languages.
It's not open source (as in FOSS)
The Lamdera approach integrates server infrastructure and compiler tooling to make type-safe migration checking and live-reload deployments possible, making it a software-as-a-service offering.
Lamdera is a paid product with a free "play" tier. See the pricing.
Source-available licenses are available for businesses, see the enterprise offering.
There is a high level of vendor lock-in
Lamdera covers setting up and writing infrastructure, deployments, type-safe migrations and versioning, type-safe networking, end-to-end type checking.
The cost of leaving Lamdera is the cost of implementing all these items yourself or finding some alternative (for which there are no known direct competitors for Elm at the time of writing).
No external database
Lamdera has no external database currently. Backend persistence is directly part of the language/platform in order to strip away complexity, with a currently unknown cap on data size.
This is motivated by my personal career experience; 95% of web projects I've been involved with haven't had more than a few hundred megabytes of persisted data over their lifetime.
If you know your data sets will grow very quickly (i.e. 1GB+), Lamdera is likely not for you right now.
It is not “web-scale”
Lamdera uses the Elm language and The Elm Architecture (TEA), which means it has a single-threaded async runtime, similar to Node.js.
Because of the integrated database, Lamdera apps currently only scale vertically.
If you need sustained loads of much more than 1000/req/s, or large (> 1GB) operational data-sets, Lamdera probably won’t work for you right now.
It is in Alpha early stage software
Lamdera has not yet hit a July 2021: Lamdera is now past v1.v1.0 release. It is alpha-quality software, currently focused on exploration and experimentation.
It is currently built on top of Elm 0.19.0, so some bugs fixed in 0.19.1 are still present. Dec 2020: Lamdera is now on Elm 0.19.1!
It is not secure or stable. Lamdera is now quite stable, with some apps having run for over 2 years.
There is no guarantee you won't lose your data. Lamdera apps have daily snapshot backups, and realtime Msg backups, allowing for intra-snapshot reconstructions if needed.
Restricted user-written Javascript
Lamdera intentionally restricts user-written Javascript. This makes things like type-safe live-reload deployments possible to guarantee. As a result, Backend ports/JS are not supported.
We're exploring a limited set of frontend-only javascript via the Labs elm-pkg-js exploration.
If you planned to use a bunch of npm packages, that is now possible, but that's not what Elm/Lamdera are really about.
POC request/response semantics
The current networking primitives only allow for async message passing between Frontend and Backend with no explicit failure tracking. See the Elm realworld app HTTP conversion PR for an example of what this looks like in practice.
There are no request/response network calls available in Lamdera currently. Update: There is now a Labs HTTP POST RPC API exploration.
It does not support old browsers
Lamdera's current target is modern browsers, roughly meaning mainstream browser versions released mid-2017 and onwards. IE11 is not supported.
WIP IDE integrations
Most Elm IDE tooling today relies on the existence of ~/.elm and elm-stuff, whereas Lamdera uses ~/.lamdera and lamdera-stuff to prevent corrupting your Elm caches.
Some people have found some workarounds to get things working, but it's not yet ideal.
Dec 2020: Elm IDE and tooling is now supported!
Still curious?
If you're wondering what the excitement for Lamdera is, check out the Lamdera Overview for the other side of the story!
Did I miss something? If so, let me know at hello@lamdera.com.