diff --git a/README.md b/README.md
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+# `haskell-nix.cabalProject` bug minimal repro
+
+1. Clone this repo.
+2. Run `nix build -f . dummy-app.components.exes.dummy-app`.
+
+Expected output:
+
+```
+trace: Using latest index state!
+trace: Using index-state: 2019-12-14T00:00:00Z
+builder for '/nix/store/g5023y5h06iy1bj076zzaaza0v8c80w3-plan-to-nix-pkgs.drv' failed with exit code 128; last 2 log lines:
+  Cloning into '/build/tmp.UZdw0uapal/dist-newstyle/src/canonical_-1f90751276f12f5a'...
+  fatal: unable to access 'http://github.com/well-typed/canonical-json/': Could not resolve host: github.com
+[1 built (1 failed), 0.0 MiB DL]
+error: build of '/nix/store/g5023y5h06iy1bj076zzaaza0v8c80w3-plan-to-nix-pkgs.
+```