alpine: Install xelatex and friends

x86_64-linux-alpine/Dockerfile

-FROM alpine:3.11.5
+FROM alpine:3.12.0
 
 SHELL ["/bin/ash", "-eo", "pipefail", "-c"]
 
@@ -6,28 +6,32 @@ RUN echo "Installing GHC build dependencies..." && \
     apk add --no-cache \
         autoconf=~2.69 \
         automake=~1.16 \
-        binutils-gold=~2.33 \
+        binutils-gold=~2.34 \
         build-base=~0.5 \
-        coreutils=~8.31 \
+        coreutils=~8.32 \
         cpio=~2.13 \
-        linux-headers=~4.19 \
-        libffi-dev=~3.2 \
+        linux-headers=~5.4 \
+        libffi-dev=~3.3 \
         musl-dev=~1 \
-        ncurses-dev=~6.1 \
-        ncurses-static=~6.1 \
+        ncurses-dev=~6.2 \
+        ncurses-static=~6.2 \
         python3=~3.8 \
-        py3-sphinx=~2.2 \
+        py3-sphinx=~2.4 \
         zlib-dev=~1.2 \
         xz=~5.2 \
         bash=~5.0 \
-        git=~2.24 \
+        git=~2.26 \
         wget=~1.20 \
-        sudo=~1.8 \
+        sudo=~1.9 \
         grep=~3 \
-        curl=~7.67 \
-        gmp-dev=~6.1 \
-        cabal=~2.4 \
-        ghc=~8.6
+        curl=~7.69 \
+        gmp-dev=~6.2 \
+        cabal=~3.2 \
+        ghc=~8.8 \
+        texlive=~20190410 \
+        texlive-xetex=~20190410 \
+        texmf-dist-latexextra=~2020 \
+        ttf-dejavu=~2.37
 
 WORKDIR /tmp
 # Install GHC
@@ -42,6 +46,7 @@ RUN ln -s /usr/lib/libncursesw.so.6 /usr/lib/libtinfow.so.6
 WORKDIR /tmp/ghc-$GHC_VERSION
 RUN ./configure --disable-ld-override --prefix=/opt/ghc/$GHC_VERSION; \
     make install;
+ENV BOOT_GHC /usr/bin/ghc
 
 WORKDIR /tmp
 RUN rm -rf /tmp/ghc-$GHC_VERSION
@@ -54,10 +59,10 @@ USER ghc
 WORKDIR /home/ghc/
 
 # Install cabal
-ENV BOOT_GHC /usr/bin/ghc
-RUN cabal v2-update && \
-    cabal v2-install cabal-install --constraint 'cabal-install ^>= 3.0' -w $BOOT_GHC
-ENV PATH /home/ghc/.cabal/bin:$PATH
+# N.B. We currently cabal-install from the Alpine repository
+#RUN cabal v2-update && \
+#    cabal v2-install cabal-install --constraint 'cabal-install ^>= 3.0' -w $BOOT_GHC
+#ENV PATH /home/ghc/.cabal/bin:$PATH
 
 # Build Haskell tools
 RUN cabal user-config update && \