Rename build/ to builders/ to avoid looking like build output

builders/linux.aarch64/Dockerfile

@@ -0,0 +1,40 @@
+FROM ubuntu:20.04
+
+ENV TARGET aarch64-linux-gnu
+ENV TARGETNAME linux.aarch64
+
+# Build dependencies
+USER root
+ENV DEBIAN_FRONTEND noninteractive
+
+# These deps are from 20.04, because GHC's compiler/llvm support moves slowly
+RUN apt-get update && apt-get install -y llvm gcc-$TARGET
+
+# The rest are from 22.10
+RUN sed -e 's/focal/kinetic/g' -i /etc/apt/sources.list
+# Kinetic does not receive updates anymore, switch to last available
+RUN sed -e 's/archive.ubuntu.com/old-releases.ubuntu.com/g' -i /etc/apt/sources.list
+RUN sed -e 's/security.ubuntu.com/old-releases.ubuntu.com/g' -i /etc/apt/sources.list
+
+RUN apt-get update && apt-get install -y ghc alex happy automake autoconf build-essential curl qemu-user-static
+
+# Build GHC
+WORKDIR /ghc
+RUN curl -L "https://downloads.haskell.org/~ghc/9.2.8/ghc-9.2.8-src.tar.xz" | tar xJ --strip-components=1
+RUN ./boot && ./configure --host x86_64-linux-gnu --build x86_64-linux-gnu --target "$TARGET"
+RUN cp mk/flavours/quick-cross.mk mk/build.mk && make -j "$(nproc)"
+RUN make install
+RUN curl -L "https://downloads.haskell.org/~cabal/cabal-install-3.9.0.0/cabal-install-3.9-x86_64-linux-alpine.tar.xz" | tar xJv -C /usr/local/bin
+
+# Due to an apparent cabal bug, we specify our options directly to cabal
+# It won't reuse caches if ghc-options are specified in ~/.cabal/config
+ENV CABALOPTS "--ghc-options;-split-sections -optc-Os -optc-Wl,--gc-sections -optc-fPIC;--with-ghc=$TARGET-ghc;--with-hc-pkg=$TARGET-ghc-pkg;-c;hashable -arch-native"
+
+# Prebuild the dependencies
+RUN cabal update && IFS=';' && cabal install --dependencies-only $CABALOPTS ShellCheck
+
+# Copy the build script
+COPY build /usr/bin
+
+WORKDIR /scratch
+ENTRYPOINT ["/usr/bin/build"]

builders/linux.aarch64/build

@@ -0,0 +1,14 @@
+#!/bin/sh
+set -xe
+{
+  tar xzv --strip-components=1
+  chmod +x striptests && ./striptests
+  mkdir "$TARGETNAME"
+  ( IFS=';'; cabal build $CABALOPTS --enable-executable-static )
+  find . -name shellcheck -type f -exec mv {} "$TARGETNAME/" \;
+  ls -l "$TARGETNAME"
+  "$TARGET-strip" -s "$TARGETNAME/shellcheck"
+  ls -l "$TARGETNAME"
+  qemu-aarch64-static "$TARGETNAME/shellcheck" --version
+} >&2
+tar czv "$TARGETNAME"

builders/linux.aarch64/tag

@@ -0,0 +1 @@
+koalaman/scbuilder-linux-aarch64