diff --git a/pkgs/development/compilers/smlnj/default.nix b/pkgs/development/compilers/smlnj/default.nix
index c7322d9ef99e..d86a7121f104 100644
--- a/pkgs/development/compilers/smlnj/default.nix
+++ b/pkgs/development/compilers/smlnj/default.nix
@@ -6,112 +6,47 @@
 }:
 let
   version = "110.99.6.1";
-  baseurl = "http://smlnj.cs.uchicago.edu/dist/working/${version}";
+  baseurl = "https://smlnj.cs.uchicago.edu/dist/working/${version}";
 
   arch = if stdenv.hostPlatform.is64bit then "64" else "32";
 
-  boot32 = {
-    url = "${baseurl}/boot.x86-unix.tgz";
-    hash = "sha256-2yBY0wGZ8B1jYC5os9SfH6eKJoWlQ4rAclBC3Pnacoc=";
-  };
-  boot64 = {
-    url = "${baseurl}/boot.amd64-unix.tgz";
-    hash = "sha256-kUabK03MdSYVRWhWKl3kS32SExUYpM3MtLU0mCxhiaQ=";
-  };
+  hashes = builtins.fromJSON (builtins.readFile ./hashes.json);
 
-  bootBinary = if stdenv.hostPlatform.is64bit then boot64 else boot32;
+  fetchSource =
+    name:
+    fetchurl {
+      url = "${baseurl}/${name}";
+      hash = hashes.${name};
+    };
 
-  sources = map fetchurl [
-    bootBinary
-    {
-      url = "${baseurl}/config.tgz";
-      hash = "sha256-9BJPpa/xouqi3j39WsfzlRys4z1yxTdbYttHF5VwCVw=";
-    }
-    {
-      url = "${baseurl}/cm.tgz";
-      hash = "sha256-A3crC5EWX4kEB6olwdaObglQgkBBNqcBSCi/pQR5Wdw=";
-    }
-    {
-      url = "${baseurl}/compiler.tgz";
-      hash = "sha256-cTgkc5opaEXskdzt5yYsdjyF5m9846t2SyEiwY6W3HU=";
-    }
-    {
-      url = "${baseurl}/runtime.tgz";
-      hash = "sha256-JiNzfuZnp1eWQPNZBb9SPmQXtwgknpoGl+38iqUU3W4=";
-    }
-    {
-      url = "${baseurl}/system.tgz";
-      hash = "sha256-HUn8YCxlLe6+e5H9oMJjIoG23GBF3thMlHEkSGLZTus=";
-    }
-    {
-      url = "${baseurl}/MLRISC.tgz";
-      hash = "sha256-MPNpYhrbsIbVEOzJ7GIEQCm/7F/Jnxj0UXS7FeTp+7o=";
-    }
-    {
-      url = "${baseurl}/smlnj-lib.tgz";
-      hash = "sha256-1tp5waPl7MCWS4kIUFm/woQeeRfCjkpgSxHpGb+ymTM=";
-    }
-    {
-      url = "${baseurl}/old-basis.tgz";
-      hash = "sha256-I6DJRfIx+09ynFKXZ63dDWRpv0pEljWciAarK/EhQ/s=";
-    }
-    {
-      url = "${baseurl}/ckit.tgz";
-      hash = "sha256-vi6dSZISL+KWkpp/jxLPCNBno+qTYThvbExZ5R5L7Wc=";
-    }
-    {
-      url = "${baseurl}/nlffi.tgz";
-      hash = "sha256-WfYmX7dhrBqtE4juDVNyjuFtsJ1H+B7rJY2BXJYtKNM=";
-    }
-    {
-      url = "${baseurl}/cml.tgz";
-      hash = "sha256-5rZzp5IUj/xZX0fyeoNMohyTz1ifdY6Anu/Hg0spDQw=";
-    }
-    {
-      url = "${baseurl}/eXene.tgz";
-      hash = "sha256-c5QnjAQTtlBgYE6DGFMNDbu9ILSEVZgzs/u0bIowfHc=";
-    }
-    {
-      url = "${baseurl}/ml-lpt.tgz";
-      hash = "sha256-aRYFTEEl4td7LQ0LhsXGLtJ/ptwCDV1m9GeDtM7+vlo=";
-    }
-    {
-      url = "${baseurl}/ml-lex.tgz";
-      hash = "sha256-ZwO3xQUDaD2f7Tsro6kkahT7vSN1JvQbLkwY/m7xSIs=";
-    }
-    {
-      url = "${baseurl}/ml-yacc.tgz";
-      hash = "sha256-DBR4xmKiSA5on7+YDz7Zr8qBA6aD1fS64+g69ukSprc=";
-    }
-    {
-      url = "${baseurl}/ml-burg.tgz";
-      hash = "sha256-4ruWhGjxny97eUD9Gk4FakqEZzNHwJp7uSa97ET20p0=";
-    }
-    {
-      url = "${baseurl}/pgraph.tgz";
-      hash = "sha256-kDyaAMB6Pt3CdAna+V8aLfTx8Tj6a5vPfuSxtpga08w=";
-    }
-    {
-      url = "${baseurl}/trace-debug-profile.tgz";
-      hash = "sha256-AD9KWsskRkjTFYiRCIm0qj02sIBHG6HtBM5wKMBqeXY=";
-    }
-    {
-      url = "${baseurl}/heap2asm.tgz";
-      hash = "sha256-OHNPMErNoLpYuatgbgYlU/mMB4JXQ4aA50WZ2BHtt3I=";
-    }
-    {
-      url = "${baseurl}/smlnj-c.tgz";
-      hash = "sha256-Vure6h0TKqne5+5MJBX9cRkBgmrJ/kKVLUzrIIiH7lE=";
-    }
-    {
-      url = "${baseurl}/doc.tgz";
-      hash = "sha256-PliWxCffISPrAO7Zan33recFLRmGoqZLKHOzSEP0PEk=";
-    }
-    {
-      url = "${baseurl}/asdl.tgz";
-      hash = "sha256-O6/g20/hsMTG3CvMA59btjG+4UdUbGhMHkizESKJDEA=";
-    }
+  bootSource = if stdenv.hostPlatform.is64bit then "boot.amd64-unix.tgz" else "boot.x86-unix.tgz";
+
+  sources = map fetchSource [
+    bootSource
+    "config.tgz"
+    "cm.tgz"
+    "compiler.tgz"
+    "runtime.tgz"
+    "system.tgz"
+    "MLRISC.tgz"
+    "smlnj-lib.tgz"
+    "old-basis.tgz"
+    "ckit.tgz"
+    "nlffi.tgz"
+    "cml.tgz"
+    "eXene.tgz"
+    "ml-lpt.tgz"
+    "ml-lex.tgz"
+    "ml-yacc.tgz"
+    "ml-burg.tgz"
+    "pgraph.tgz"
+    "trace-debug-profile.tgz"
+    "heap2asm.tgz"
+    "smlnj-c.tgz"
+    "doc.tgz"
+    "asdl.tgz"
   ];
+
 in
 stdenv.mkDerivation {
   pname = "smlnj";
@@ -152,6 +87,8 @@ stdenv.mkDerivation {
     done
   '';
 
+  passthru.updateScript = ./update.sh;
+
   meta = {
     description = "Standard ML of New Jersey, a compiler";
     homepage = "http://smlnj.org";
@@ -160,13 +97,12 @@ stdenv.mkDerivation {
       "x86_64-linux"
       "i686-linux"
       "x86_64-darwin"
+      "aarch64-darwin"
     ];
     maintainers = with lib.maintainers; [
       skyesoss
       thoughtpolice
     ];
     mainProgram = "sml";
-    # never built on x86_64-darwin since first introduction in nixpkgs
-    broken = stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isx86_64;
   };
 }
diff --git a/pkgs/development/compilers/smlnj/hashes.json b/pkgs/development/compilers/smlnj/hashes.json
new file mode 100644
index 000000000000..a3319e2625d2
--- /dev/null
+++ b/pkgs/development/compilers/smlnj/hashes.json
@@ -0,0 +1,27 @@
+{
+  "boot.x86-unix.tgz": "sha256-2yBY0wGZ8B1jYC5os9SfH6eKJoWlQ4rAclBC3Pnacoc=",
+  "boot.amd64-unix.tgz": "sha256-kUabK03MdSYVRWhWKl3kS32SExUYpM3MtLU0mCxhiaQ=",
+  "config.tgz": "sha256-9BJPpa/xouqi3j39WsfzlRys4z1yxTdbYttHF5VwCVw=",
+  "cm.tgz": "sha256-A3crC5EWX4kEB6olwdaObglQgkBBNqcBSCi/pQR5Wdw=",
+  "compiler.tgz": "sha256-cTgkc5opaEXskdzt5yYsdjyF5m9846t2SyEiwY6W3HU=",
+  "runtime.tgz": "sha256-JiNzfuZnp1eWQPNZBb9SPmQXtwgknpoGl+38iqUU3W4=",
+  "system.tgz": "sha256-HUn8YCxlLe6+e5H9oMJjIoG23GBF3thMlHEkSGLZTus=",
+  "MLRISC.tgz": "sha256-MPNpYhrbsIbVEOzJ7GIEQCm/7F/Jnxj0UXS7FeTp+7o=",
+  "smlnj-lib.tgz": "sha256-1tp5waPl7MCWS4kIUFm/woQeeRfCjkpgSxHpGb+ymTM=",
+  "old-basis.tgz": "sha256-I6DJRfIx+09ynFKXZ63dDWRpv0pEljWciAarK/EhQ/s=",
+  "ckit.tgz": "sha256-vi6dSZISL+KWkpp/jxLPCNBno+qTYThvbExZ5R5L7Wc=",
+  "nlffi.tgz": "sha256-WfYmX7dhrBqtE4juDVNyjuFtsJ1H+B7rJY2BXJYtKNM=",
+  "cml.tgz": "sha256-5rZzp5IUj/xZX0fyeoNMohyTz1ifdY6Anu/Hg0spDQw=",
+  "eXene.tgz": "sha256-c5QnjAQTtlBgYE6DGFMNDbu9ILSEVZgzs/u0bIowfHc=",
+  "ml-lpt.tgz": "sha256-aRYFTEEl4td7LQ0LhsXGLtJ/ptwCDV1m9GeDtM7+vlo=",
+  "ml-lex.tgz": "sha256-ZwO3xQUDaD2f7Tsro6kkahT7vSN1JvQbLkwY/m7xSIs=",
+  "ml-yacc.tgz": "sha256-DBR4xmKiSA5on7+YDz7Zr8qBA6aD1fS64+g69ukSprc=",
+  "ml-burg.tgz": "sha256-4ruWhGjxny97eUD9Gk4FakqEZzNHwJp7uSa97ET20p0=",
+  "pgraph.tgz": "sha256-kDyaAMB6Pt3CdAna+V8aLfTx8Tj6a5vPfuSxtpga08w=",
+  "trace-debug-profile.tgz": "sha256-AD9KWsskRkjTFYiRCIm0qj02sIBHG6HtBM5wKMBqeXY=",
+  "heap2asm.tgz": "sha256-OHNPMErNoLpYuatgbgYlU/mMB4JXQ4aA50WZ2BHtt3I=",
+  "smlnj-c.tgz": "sha256-Vure6h0TKqne5+5MJBX9cRkBgmrJ/kKVLUzrIIiH7lE=",
+  "doc.tgz": "sha256-PliWxCffISPrAO7Zan33recFLRmGoqZLKHOzSEP0PEk=",
+  "asdl.tgz": "sha256-O6/g20/hsMTG3CvMA59btjG+4UdUbGhMHkizESKJDEA=",
+  "version": "110.99.6.1"
+}
diff --git a/pkgs/development/compilers/smlnj/update.sh b/pkgs/development/compilers/smlnj/update.sh
new file mode 100755
index 000000000000..a5c9cd96d055
--- /dev/null
+++ b/pkgs/development/compilers/smlnj/update.sh
@@ -0,0 +1,60 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -I nixpkgs=./. -i bash -p bash curl nix-prefetch jq
+# shellcheck shell=bash
+
+set -euo pipefail
+
+dir="$(dirname "$0")"
+url="https://smlnj.cs.uchicago.edu/dist/working/"
+hashfile="$dir/hashes.json"
+nixfile="$dir/default.nix"
+
+version="$(curl --silent "$url" \
+    | sed -n 's:.*<b>\([0-9]\{3\}\.[0-9.-]\+\)</b>.*:\1:p' \
+    | head -n1)"
+
+echo "Latest SML/NJ release: $version"
+
+if [[ -e "$hashfile" ]]; then
+    old_version="$(jq -r .version "$hashfile")"
+    if [[ $old_version = "$version" ]]; then
+        echo "Package is already up-to-date, skipping"
+        exit 0
+    fi
+    echo "Upgrading from $old_version to $version"
+else
+    echo "Generating hashes for $version"
+fi
+
+files=(
+    boot.amd64-unix.tgz boot.x86-unix.tgz
+    config.tgz cm.tgz compiler.tgz runtime.tgz system.tgz MLRISC.tgz
+    smlnj-lib.tgz old-basis.tgz ckit.tgz nlffi.tgz cml.tgz eXene.tgz ml-lpt.tgz
+    ml-lex.tgz ml-yacc.tgz ml-burg.tgz pgraph.tgz trace-debug-profile.tgz
+    heap2asm.tgz smlnj-c.tgz doc.tgz asdl.tgz
+)
+
+tmpdir="$(mktemp --directory)"
+trap 'rm -rf -- "$tmpdir"' EXIT
+
+declare -a pids=()
+
+for file in "${files[@]}"; do
+    nix-prefetch --silent fetchurl --url "$url/$version/$file" > "$tmpdir/$file" &
+    pids+=($!)
+done
+
+for pid in "${pids[@]}"; do
+    wait "$pid"
+done
+
+printf '{\n' > "$hashfile"
+for file in "${files[@]}"; do
+    printf '  "%s": "%s",\n' "$file" "$(cat "$tmpdir/$file")" >> "$hashfile"
+done
+printf '  "version": "%s"\n' "$version" >> "$hashfile"
+printf '}\n' >> "$hashfile"
+
+sed --in-place 's:version = "[0-9.]\+";:version = "'"$version"'";:' "$nixfile"
+
+echo "Done"