2 modules / 2500LOC takes nearly 3 minutes to build

I tested this from a brand new MacBook 15" with 8 threads x 2.8 GHz Intel Core i7 / 16 GB RAM on OS X:

$ time stack build
WARNING: /Users/kvanb/git/github-webhooks/github-webhooks.cabal was generated with a newer version of hpack, please upgrade and try again.
github-webhooks-1.0.0: unregistering (local file changes: github-webhooks.cabal package.yaml spec/DecodeEventsSpec.hs spec/Spec.hs src/GitHub/Data/Webhooks...)
github-webhooks-1.0.0: configure (lib)
Configuring github-webhooks-1.0.0...
github-webhooks-1.0.0: build (lib)
Preprocessing library github-webhooks-1.0.0...
[1 of 3] Compiling Paths_github_webhooks ( .stack-work/dist/x86_64-osx/Cabal-1.24.2.0/build/autogen/Paths_github_webhooks.hs, .stack-work/dist/x86_64-osx/Cabal-1.24.2.0/build/Paths_github_webhooks.o )
[2 of 3] Compiling GitHub.Data.Webhooks.Payload ( src/GitHub/Data/Webhooks/Payload.hs, .stack-work/dist/x86_64-osx/Cabal-1.24.2.0/build/GitHub/Data/Webhooks/Payload.o )
[3 of 3] Compiling GitHub.Data.Webhooks.Events ( src/GitHub/Data/Webhooks/Events.hs, .stack-work/dist/x86_64-osx/Cabal-1.24.2.0/build/GitHub/Data/Webhooks/Events.o )
github-webhooks-1.0.0: copy/register
Installing library in
/Users/kvanb/git/github-webhooks/.stack-work/install/x86_64-osx/lts-9.18/8.0.2/lib/x86_64-osx-ghc-8.0.2/github-webhooks-1.0.0-LDmeffpkXvwH6ZXCPE95ke
Registering github-webhooks-1.0.0...

real	2m49.342s
user	2m42.441s
sys	0m5.805s

Source code has about 30 derivations of the form:

type IssueState = Text

data HookIssue = HookIssue
    { whIssueUrl                :: !URL
    , whIssueLabelsUrl          :: !URL
    , whIssueCommentsUrl        :: !URL
    , whIssueEventsUrl          :: !URL
    , whIssueHtmlUrl            :: !URL
    , whIssueId                 :: !Int
    , whIssueNumber             :: !Int
    , whIssueTitle              :: !Text
    , whIssueUser               :: !HookUser
    , whIssueLabels             :: !(Vector HookIssueLabels)
    , whIssueState              :: IssueState
    , whIssueIsLocked           :: !Bool
    , whIssueAssignee           :: !(Maybe HookUser)
    , whIssueMilestone          :: !(Maybe HookMilestone)
    , whIssueCommentCount       :: !Int
    , whIssueCreatedAt          :: !UTCTime
    , whIssueUpdatedAt          :: !UTCTime
    , whIssueClosedAt           :: !(Maybe UTCTime)
    , whIssueBody               :: !Text
    }
    deriving (Eq, Show, Typeable, Data, Generic)

instance NFData HookIssue where rnf = genericRnf

Steps to reproduce

1. clone https://github.com/onrock-eng/github-webhooks
2. checkout sha 40a7ecc3a5845717055ee372b89e645a498cf1e2
3. time stack build

This is really really **really** slow.

Trac metadata

Trac field	Value
Version	8.2.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	kvanberendonck@gmail.com
Operating system
Architecture