diff -Np1 a/stack.yaml b/stack.yaml
*** a/stack.yaml	2020-03-04 17:55:17.530246000 +0600
--- b/stack.yaml	2020-03-04 22:38:18.133458418 +0600
*************** extra-package-dbs: []
*** 86,87 ****
  # Allow a newer minor version of GHC than the snapshot specifies
! # compiler-check: newer-minor
\ No newline at end of file
--- 86,107 ----
  # Allow a newer minor version of GHC than the snapshot specifies
! # compiler-check: newer-minor
! 
! # Alternative mirrors to fix s3.amazonaws.com connection issues
! # Details: https://docs.haskellstack.org/en/stable/yaml_configuration/#package-indices
! package-indices:
! - download-prefix: https://hackage.haskell.org/
!   hackage-security:
!     keyids:
!     - 0a5c7ea47cd1b15f01f5f51a33adda7e655bc0f0b0615baa8e271f4c3351e21d
!     - 1ea9ba32c526d1cc91ab5e5bd364ec5e9e8cb67179a471872f6e26f0ae773d42
!     - 280b10153a522681163658cb49f632cde3f38d768b736ddbc901d99a1a772833
!     - 2a96b1889dc221c17296fcc2bb34b908ca9734376f0f361660200935916ef201
!     - 2c6c3627bd6c982990239487f1abd02e08a02e6cf16edb105a8012d444d870c3
!     - 51f0161b906011b52c6613376b1ae937670da69322113a246a09f807c62f6921
!     - 772e9f4c7db33d251d5c6e357199c819e569d130857dc225549b40845ff0890d
!     - aa315286e6ad281ad61182235533c41e806e5a787e0b6d1e7eef3f09d137d2e9
!     - fe331502606802feac15e514d9b9ea83fee8b6ffef71335479a2e68d84adc6b0
!     key-threshold: 3 # number of keys required
! 
!     # ignore expiration date, see https://github.com/commercialhaskell/stack/pull/4614
!     ignore-expiry: true
