$ ob run
...
ob: Couldn't resolve dependency for base >=4.7 && <4.13
CallStack (from HasCallStack):
  error, called at src/Obelisk/Command/Run.hs:536:14 in obelisk-command-0.9.0.1-GO7lnPern5Sro2o9KYnM1:Obelisk.Command.Run

$ ob run --verbose
Starting Obelisk </nix/store/5qhw99ipn683vik513frrqraz8c3p07j-obelisk-command-0.9.0.1/bin/.ob-wrapped> args=["run","--verbose"] logging-level=Debug
Thunk specification git-v7 did not match "./.obelisk/impl": ReadThunkError_UnrecognizedPaths ("./.obelisk/impl/github.json" :| [])
Thunk specification github-v8 matched "./.obelisk/impl"
./.obelisk/impl: command not cached, building ...
Creating process: nix-build ./.obelisk/impl -A command --out-link ./.obelisk/impl/.attr-cache/command.out
✔ Built on ./.obelisk/impl [command]
Handing off to ./.obelisk/impl/.attr-cache/command.out/bin/ob
Starting Obelisk </nix/store/5qhw99ipn683vik513frrqraz8c3p07j-obelisk-command-0.9.0.1/bin/.ob-wrapped> args=["--no-handoff","run","--verbose"] logging-level=Debug
Finding packages with root "." and interpret paths:
└─ /
   └─ home
      └─ user
         └─ repos
            └─ my-app [Interpret]
Creating process: /nix/store/k0kpf3r2k1d8p9h0gmx23msw3qrybkfk-findutils-4.9.0/bin/find -L . -name .obelisk -type d
Excluding obelisk packages: 
Creating process: /nix/store/k0kpf3r2k1d8p9h0gmx23msw3qrybkfk-findutils-4.9.0/bin/find -L /home/user/work/my-app $'(' -name $'*.cabal' -o -name package.yaml $')' -a -type f -not -path $'*/.attr-cache/*' -not -path $'*/lib/asset/manifest/*'
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix eval --impure --expr $'(let a = import ./. {}; in toString (a.reflex.nixpkgs.lib.isDerivation a.passthru.staticFilesImpure))' --raw
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix eval -f . passthru.staticFilesImpure --raw
Creating process: /nix/store/n95s7s6ilkjc7xwqml93acxzj6k0hsfn-coreutils-9.1/bin/ln -sfT /home/user/work/my-app/static ./static.out
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix-build --no-out-link -E $'(let a = import ./. {}; in a.passthru.processedStatic.haskellManifest)'
Assets impurely loaded from: /home/user/work/my-app/static
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix eval --impure --expr $'(import .obelisk/impl {}).nixpkgs.path'
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix-shell -E $'{root, pkgs, shell}: ((import root {}).passthru.__unstable__.self.extend (_: _: {shellPackages = builtins.fromJSON pkgs;})).project.shells.${shell}' --arg root ./. --argstr pkgs $'{"backend":"/home/user/work/my-app/backend","common":"/home/user/work/my-app/common","frontend":"/home/user/work/my-app/frontend","obelisk-generated-static":"/nix/store/4amdsdk476sa6fp87gqpbqsl72gqfcm4-asset-manifest-haskellManifest","reflex-dom":"/home/user/work/my-app/reflex-dom"}' --argstr shell ghc --run $'export $\'NIX_PATH=nixpkgs=/nix/store/ahg8gp1z3qrw1ds5vx2324j72i7y9vjg-source\' ; bash -c \'type -p ghc\''
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix eval --impure --expr $'(import .obelisk/impl {}).nixpkgs.path'
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix-shell -E $'{root, pkgs, shell}: ((import root {}).passthru.__unstable__.self.extend (_: _: {shellPackages = builtins.fromJSON pkgs;})).project.shells.${shell}' --arg root ./. --argstr pkgs $'{"backend":"/home/user/work/my-app/backend","common":"/home/user/work/my-app/common","frontend":"/home/user/work/my-app/frontend","obelisk-generated-static":"/nix/store/4amdsdk476sa6fp87gqpbqsl72gqfcm4-asset-manifest-haskellManifest","reflex-dom":"/home/user/work/my-app/reflex-dom"}' --argstr shell ghc --run $'export $\'NIX_PATH=nixpkgs=/nix/store/ahg8gp1z3qrw1ds5vx2324j72i7y9vjg-source\' ; bash -c \'type -p ghc-pkg\''
Creating process: /nix/store/7wfnj6hg24p9v212qfx81a16f6rnaqzy-nix-2.11.0/bin/nix eval --impure --expr $'(import .obelisk/impl {}).nixpkgs.path'
ob: Couldn't resolve dependency for base >=4.7 && <4.13
CallStack (from HasCallStack):
  error, called at src/Obelisk/Command/Run.hs:536:14 in obelisk-command-0.9.0.1-GO7lnPern5Sro2o9KYnM1:Obelisk.Command.Run