diff --git a/README.md b/README.md
index 60a4373..62d2643 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,12 @@ mkdir myprojectname && cd myprojectname
 init-haskell
 ```
 
+The above will default to using GHC 8.10.7. If you'd like to use a different version, simply pass the full version as an argument:
+
+```
+init-haskell 9.2.1
+```
+
 ### Build and run
 
 ```
diff --git a/init-haskell b/init-haskell
index eccb7b1..e012e0f 100755
--- a/init-haskell
+++ b/init-haskell
@@ -1,10 +1,23 @@
 #! /usr/bin/env nix-shell
-#! nix-shell --pure --keep NIX_SSL_CERT_FILE --keep GITHUB_TOKEN -i bash -p git mustache-go niv direnv nix
+#! nix-shell --pure --keep NIX_SSL_CERT_FILE --keep GITHUB_TOKEN -i bash -p git mustache-go jq niv direnv nix
 set -Eeuxo pipefail
 
 # init-haskell location
 base=$(dirname "$(readlink -f "$0")")
 
+ghc=${1:-8.10.7}
+ghcparts=(${ghc//./ })
+ghcmajor=${ghcparts[0]}
+ghcminor=${ghcparts[1]}
+ghcpatch=${ghcparts[2]}
+
+snapshot="2022-01-01T00:00:00Z"
+cabaltimestamp=~/.cabal/packages/hackage.haskell.org/timestamp.json
+
+if [ -f $cabaltimestamp ]; then
+  snapshot=$(jq -r '.signed | select(._type == "Timestamp") | .expires' $cabaltimestamp)
+fi
+
 # Variables
 data=$(mktemp)
 projectname=${PWD##*/}
@@ -12,11 +25,11 @@ cat <<EOF >$data
 { "author": "$(git config user.name)"
 , "email": "$(git config user.email)"
 , "ghc":
-  { major: 8
-  , minor: 10
-  , patch: 7
+  { major: ${ghcmajor}
+  , minor: ${ghcminor}
+  , patch: ${ghcpatch}
   }
-, "snapshot": "2022-03-01T00:00:00Z"
+, "snapshot": "${snapshot}"
 , "projectname": "${projectname}"
 }
 EOF