My .spacemacs when trying to get a full features Haskell setup that is stack-aware

.spacemacs

;; -*- mode: emacs-lisp -*-
;; This file is loaded by Spacemacs at startup.
;; It must be stored in your home directory.

(defun dotspacemacs/layers ()
  "Configuration Layers declaration."
  (setq-default
   ;; List of additional paths where to look for configuration layers.
   ;; Paths must have a trailing slash (i.e. `~/.mycontribs/')
   dotspacemacs-configuration-layer-path '()
   ;; List of configuration layers to load. If it is the symbol `all' instead
   ;; of a list then all discovered layers will be installed.
   dotspacemacs-configuration-layers
   '(
     ;; ----------------------------------------------------------------
     ;; Example of useful layers you may want to use right away.
     ;; Uncomment some layer names and press <SPC f e R> (Vim style) or
     ;; <M-m f e R> (Emacs style) to install them.
     ;; ----------------------------------------------------------------
     auto-completion
     ;; better-defaults
     emacs-lisp
     (git :variables
          git-enable-github-support t)
     markdown
     org
     (shell :variables
            shell-default-height 30
            shell-default-position 'bottom
            shell-default-term-shell "/bin/zsh")
     syntax-checking
     version-control
     (haskell :variables
              haskell-enable-hindent-style "chris-done"
              haskell-enable-shm-support t)
     )
   ;; List of additional packages that will be installed without being
   ;; wrapped in a layer. If you need some configuration for these
   ;; packages then consider to create a layer, you can also put the
   ;; configuration in `dotspacemacs/config'.
   dotspacemacs-additional-packages '()
   ;; A list of packages and/or extensions that will not be install and loaded.
   dotspacemacs-excluded-packages '()
   ;; If non-nil spacemacs will delete any orphan packages, i.e. packages that
   ;; are declared in a layer which is not a member of
   ;; the list `dotspacemacs-configuration-layers'
   dotspacemacs-delete-orphan-packages t))

(defun dotspacemacs/init ()
  "Initialization function.
This function is called at the very startup of Spacemacs initialization
before layers configuration."
  ;; This setq-default sexp is an exhaustive list of all the supported
  ;; spacemacs settings.
  (setq-default
   ;; Either `vim' or `emacs'. Evil is always enabled but if the variable
   ;; is `emacs' then the `holy-mode' is enabled at startup.
   dotspacemacs-editing-style 'vim
   ;; If non nil output loading progress in `*Messages*' buffer.
   dotspacemacs-verbose-loading nil
   ;; Specify the startup banner. Default value is `official', it displays
   ;; the official spacemacs logo. An integer value is the index of text
   ;; banner, `random' chooses a random text banner in `core/banners'
   ;; directory. A string value must be a path to an image format supported
   ;; by your Emacs build.
   ;; If the value is nil then no banner is displayed.
   dotspacemacs-startup-banner 'official
   ;; List of items to show in the startup buffer. If nil it is disabled.
   ;; Possible values are: `recents' `bookmarks' `projects'."
   dotspacemacs-startup-lists '(recents projects)
   ;; List of themes, the first of the list is loaded when spacemacs starts.
   ;; Press <SPC> T n to cycle to the next theme in the list (works great
   ;; with 2 themes variants, one dark and one light)
   dotspacemacs-themes '(solarized-light
                         solarized-dark
                         spacemacs-light
                         spacemacs-dark
                         leuven
                         monokai
                         zenburn)
   ;; If non nil the cursor color matches the state color.
   dotspacemacs-colorize-cursor-according-to-state t
   ;; Default font. `powerline-scale' allows to quickly tweak the mode-line
   ;; size to make separators look not too crappy.
   dotspacemacs-default-font '("Source Code Pro"
                               :size 13
                               :weight normal
                               :width normal
                               :powerline-scale 1.1)
   ;; The leader key
   dotspacemacs-leader-key "SPC"
   ;; The leader key accessible in `emacs state' and `insert state'
   dotspacemacs-emacs-leader-key "M-m"
   ;; Major mode leader key is a shortcut key which is the equivalent of
   ;; pressing `<leader> m`. Set it to `nil` to disable it.
   dotspacemacs-major-mode-leader-key ","
   ;; Major mode leader key accessible in `emacs state' and `insert state'
   dotspacemacs-major-mode-emacs-leader-key "C-M-m"
   ;; The command key used for Evil commands (ex-commands) and
   ;; Emacs commands (M-x).
   ;; By default the command key is `:' so ex-commands are executed like in Vim
   ;; with `:' and Emacs commands are executed with `<leader> :'.
   dotspacemacs-command-key ":"
   ;; Location where to auto-save files. Possible values are `original' to
   ;; auto-save the file in-place, `cache' to auto-save the file to another
   ;; file stored in the cache directory and `nil' to disable auto-saving.
   ;; Default value is `cache'.
   dotspacemacs-auto-save-file-location 'cache
   ;; If non nil then `ido' replaces `helm' for some commands. For now only
   ;; `find-files' (SPC f f) is replaced.
   dotspacemacs-use-ido nil
   ;; If non nil the paste micro-state is enabled. When enabled pressing `p`
   ;; several times cycle between the kill ring content.
   dotspacemacs-enable-paste-micro-state nil
   ;; Guide-key delay in seconds. The Guide-key is the popup buffer listing
   ;; the commands bound to the current keystrokes.
   dotspacemacs-guide-key-delay 0.4
   ;; If non nil a progress bar is displayed when spacemacs is loading. This
   ;; may increase the boot time on some systems and emacs builds, set it to
   ;; nil ;; to boost the loading time.
   dotspacemacs-loading-progress-bar t
   ;; If non nil the frame is fullscreen when Emacs starts up.
   ;; (Emacs 24.4+ only)
   dotspacemacs-fullscreen-at-startup nil
   ;; If non nil `spacemacs/toggle-fullscreen' will not use native fullscreen.
   ;; Use to disable fullscreen animations in OSX."
   dotspacemacs-fullscreen-use-non-native nil
   ;; If non nil the frame is maximized when Emacs starts up.
   ;; Takes effect only if `dotspacemacs-fullscreen-at-startup' is nil.
   ;; (Emacs 24.4+ only)
   dotspacemacs-maximized-at-startup nil
   ;; A value from the range (0..100), in increasing opacity, which describes
   ;; the transparency level of a frame when it's active or selected.
   ;; Transparency can be toggled through `toggle-transparency'.
   dotspacemacs-active-transparency 90
   ;; A value from the range (0..100), in increasing opacity, which describes
   ;; the transparency level of a frame when it's inactive or deselected.
   ;; Transparency can be toggled through `toggle-transparency'.
   dotspacemacs-inactive-transparency 90
   ;; If non nil unicode symbols are displayed in the mode line.
   dotspacemacs-mode-line-unicode-symbols t
   ;; If non nil smooth scrolling (native-scrolling) is enabled. Smooth
   ;; scrolling overrides the default behavior of Emacs which recenters the
   ;; point when it reaches the top or bottom of the screen.
   dotspacemacs-smooth-scrolling t
   ;; If non-nil smartparens-strict-mode will be enabled in programming modes.
   dotspacemacs-smartparens-strict-mode nil
   ;; Select a scope to highlight delimiters. Possible value is `all',
   ;; `current' or `nil'. Default is `all'
   dotspacemacs-highlight-delimiters 'all
   ;; If non nil advises quit functions to keep server open when quitting.
   dotspacemacs-persistent-server nil
   ;; List of search tool executable names. Spacemacs uses the first installed
   ;; tool of the list. Supported tools are `ag', `pt', `ack' and `grep'.
   dotspacemacs-search-tools '("ag" "pt" "ack" "grep")
   ;; The default package repository used if no explicit repository has been
   ;; specified with an installed package.
   ;; Not used for now.
   dotspacemacs-default-package-repository nil
   )
  ;; User initialization goes here
  (add-hook 'haskell-mode-hook 'turn-on-haskell-indentation)
  (add-to-list 'exec-path "~/.local/bin")
  )

;; -- Y
(defun find-file-in-split ()
  "Split the windows and start projectile find file"
  (interactive)
  (split-window-below-and-focus)
  (projectile-find-file))

(defun dotspacemacs/config ()
  "Configuration function.
 This function is called at the very end of Spacemacs initialization after
layers configuration."
)

;; Do not write anything past this comment. This is where Emacs will
;; auto-generate custom variable definitions.


(custom-set-variables
 ;; custom-set-variables was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(ahs-case-fold-search nil)
 '(ahs-default-range (quote ahs-range-whole-buffer))
 '(ahs-idle-interval 0.25)
 '(ahs-idle-timer 0 t)
 '(ahs-inhibit-face-list nil)
 '(haskell-interactive-popup-errors nil)
 '(package-selected-packages
   (quote
    (toc-org org-repo-todo org-present org-pomodoro org-bullets htmlize evil-org alert log4e gntp macrostep elisp-slime-nav diff-hl auto-complete avy names ghc company anzu iedit smartparens highlight flx flycheck haskell-mode popup pos-tip guide-key popwin request gitignore-mode projectile helm helm-core parent-mode async markdown-mode s pkg-info epl evil-leader evil bind-key dash paradox magit company-quickhelp magit-popup git-commit with-editor spinner window-numbering volatile-highlights vi-tilde-fringe use-package smooth-scrolling smeargle shm shell-pop rfringe rainbow-delimiters powerline pcre2el page-break-lines open-junk-file neotree multi-term move-text mmm-mode markdown-toc linum-relative leuven-theme info+ indent-guide ido-vertical-mode hungry-delete hl-anything hindent highlight-parentheses highlight-numbers highlight-indentation helm-themes helm-swoop helm-projectile helm-mode-manager helm-make helm-gitignore helm-flyspell helm-descbinds helm-c-yasnippet helm-ag haskell-snippets guide-key-tip google-translate golden-ratio gitconfig-mode gitattributes-mode git-timemachine git-messenger gh-md fringe-helper flycheck-pos-tip flycheck-haskell flx-ido fill-column-indicator fancy-battery expand-region exec-path-from-shell evil-visualstar evil-tutor evil-terminal-cursor-changer evil-surround evil-search-highlight-persist evil-numbers evil-nerd-commenter evil-matchit evil-lisp-state evil-jumper evil-indent-textobject evil-iedit-state evil-exchange evil-escape evil-args evil-anzu eval-sexp-fu company-statistics company-ghc company-cabal cmm-mode clean-aindent-mode buffer-move auto-yasnippet auto-highlight-symbol auto-dictionary aggressive-indent adaptive-wrap ace-window ace-link ace-jump-mode ac-ispell)))
 '(ring-bell-function (quote ignore))
 '(safe-local-variable-values
   (quote
    ((haskell-indent-spaces . 2)
     (haskell-process-args-ghci "ghci")
     (haskell-process-path-ghci . "stack")
     (haskell-process-type . stack-ghci)))))
(custom-set-faces
 ;; custom-set-faces was added by Custom.
 ;; If you edit it by hand, you could mess it up, so be careful.
 ;; Your init file should contain only one such instance.
 ;; If there is more than one, they won't work right.
 '(company-tooltip-common ((t (:inherit company-tooltip :weight bold :underline nil))))
 '(company-tooltip-common-selection ((t (:inherit company-tooltip-selection :weight bold :underline nil)))))