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+\documentclass[12pt]{beamer}
+\usetheme{metropolis}
+\usepackage{minted}
+
+\newenvironment{code}{\ttfamily}{\par}
+
+\title{servant}
+\subtitle{Defining web APIs at the type-level}
+
+\begin{document}
+\metroset{titleformat frame=smallcaps}
+\setminted{fontsize=\scriptsize}
+
+
+\maketitle
+
+\section{Introduction}
+
+\begin{frame}{Type-level DSLs?}
+  \begin{itemize}
+  \item (Uninhabited) types with attached ``meaning''
+  \item The Expression Problem (Wadler 1998)
+  \item API representation and interpretation are separated
+  \item APIs become first-class citizens
+  \end{itemize}
+\end{frame}
+
+\begin{frame}{Haskell extensions}
+  \begin{itemize}
+  \item TypeOperators
+  \item DataKinds
+  \item TypeFamilies
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]{A servant example}
+  \begin{minted}{haskell}
+    type PubAPI = "pubs" :> Get ’[JSON] [Pub]
+             :<|> "pubs" :> "tagged"
+                         :> Capture "tag" Text
+                         :> Get ’[JSON] [Pub]
+  \end{minted}
+\end{frame}
+
+\begin{frame}[fragile]{Computed types}
+  \begin{minted}{haskell}
+    type TaggedPubs = "tagged" :> Capture "tag" Text :> ...
+
+    taggedPubsHandler :: Server TaggedPubs
+    taggedPubsHandler tag = ...
+  \end{minted}
+\end{frame}
+
+\begin{frame}[fragile]{Computed types}
+  \begin{minted}{haskell}
+    type TaggedPubs = "tagged" :> Capture "tag" Text :> ...
+
+    taggedPubsHandler :: Server TaggedPubs
+    taggedPubsHandler tag = ...
+
+    Server TaggedPubs ~
+    Text -> EitherT ServantErr IO [Pub]
+  \end{minted}
+\end{frame}
+
+\section{Interpretations}
+
+\begin{frame}{servant-server}
+  The one everyone is interested in!
+
+  \begin{itemize}
+  \item Based on WAI, can run on warp
+  \item Interprets combinators with a simple \texttt{HasServer c} class
+  \item Easy to use!
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]{HasServer ...}
+  \begin{minted}{haskell}
+    instance (KnownSymbol path, HasServer sublayout)
+             => HasServer (path :> sublayout) where
+      type ServerT (path :> sublayout) m = ServerT sublayout m
+
+      route ...
+        where
+          pathString = symbolVal (Proxy :: Proxy path)
+  \end{minted}
+\end{frame}
+
+\begin{frame}[fragile]{Server example}
+  \begin{minted}{haskell}
+    type Echo = Capture "echo" Text :> Get ’[PlainText] Text
+
+    echoAPI :: Proxy Echo
+    echoAPI = Proxy
+
+    echoServer :: Server Echo
+    echoServer = return
+  \end{minted}
+\end{frame}
+
+\begin{frame}{servant-client}
+  \begin{itemize}
+  \item Generates Haskell client functions for API
+  \item Same types as API specification: For RPC the whole ``web layer'' is abstracted away
+  \item Also easy to use!
+  \end{itemize}
+\end{frame}
+
+\begin{frame}{servant-docs, servant-js ...}
+  Many other interpretations exist already, for example:
+  \begin{itemize}
+  \item Documentation generation
+  \item Foreign function export (e.g. Elm, JavaScript)
+  \item Mock-server generation
+  \end{itemize}
+\end{frame}
+
+\section{Demo}
+
+\section{Conclusion}
+
+\begin{frame}{Drawbacks}
+  \begin{itemize}
+  \item Haskell has no custom open kinds (yet)
+  \item Proxies are ugly
+  \item Errors can be a bit daunting
+  \end{itemize}
+\end{frame}
+
+\begin{frame}{Questions?}
+  Ølkartet: github.com/tazjin/pubkartet \\
+  Slides: github.com/tazjin/servant-presentation
+
+  @tazjin
+\end{frame}
+\end{document}