Add -nightly, move standard build to LTS 17

Author: snoyberg

.github/workflows/unit-tests.yml

@@ -54,6 +54,10 @@ jobs:
           stack-yaml: stack-ghc-810.yaml
           extra-suffix: ""
           stack-args: ""
+        - os: ubuntu-latest
+          stack-yaml: stack-nightly.yaml
+          extra-suffix: ""
+          stack-args: ""
         - os: ubuntu-latest
           stack-yaml: stack.yaml
           extra-suffix: "alpine"

stack-nightly.yaml

@@ -0,0 +1,26 @@
+resolver: nightly-2021-04-23
+
+packages:
+- .
+
+docker:
+  enable: false
+  repo: fpco/alpine-haskell-stack:8.10.4
+
+nix:
+  # --nix on the command-line to enable.
+  packages:
+    - zlib
+    - unzip
+flags:
+  stack:
+    developer-mode: true
+
+ghc-options:
+   "$locals": -fhide-source-paths
+
+extra-deps: []
+
+drop-packages:
+# See https://github.com/commercialhaskell/stack/pull/4712
+- cabal-install

stack.yaml

@@ -1,4 +1,4 @@
-resolver: nightly-2021-04-23
+resolver: lts-17.10
 
 packages:
 - .