diff --git a/hakyll-bootstrap/Makefile b/hakyll-bootstrap/Makefile
index 4997f61fe0bbfedf266d57bd5e35008950cd84b3..1e4e8d1871d6049bfcd58f9b8c2346ddcdc3be14 100644
--- a/hakyll-bootstrap/Makefile
+++ b/hakyll-bootstrap/Makefile
@@ -1,10 +1,8 @@
 watch: build
-	# stack exec blog -- watch
-	blog watch
+	stack exec blog --allow-different-user -- watch
 
 deploy: build 
-	# stack exec blog -- deploy
-	blog deploy
+	stack exec blog -- deploy
 
 build: Main.hs cours/math_tech_info/*.md cours/isc_physics/*.md
 	make hakyll_gen -C cours/math_tech_info
@@ -12,10 +10,10 @@ build: Main.hs cours/math_tech_info/*.md cours/isc_physics/*.md
 	make -C cours/math_tech_info
 	make -C cours/isc_physics
 	make markdown -C cours/prog_seq/slides
-	# stack build && stack exec blog -- build
+	stack build --allow-different-user && stack exec --allow-different-user blog -- build
 	# cabal install && blog build
 	# stack build && stack exec blog -- build
-	blog build
+	# blog build
 
 build_revealjs:
 	cd reveal.js && npm install && npm run build && cd ..
diff --git a/hakyll-bootstrap/stack.yaml b/hakyll-bootstrap/stack.yaml
index 814d33c50ac81a0413936ff1b1414ac08927fea2..38fe4e8c61ba4f103a3ce52f6431f644a4fb9446 100644
--- a/hakyll-bootstrap/stack.yaml
+++ b/hakyll-bootstrap/stack.yaml
@@ -17,7 +17,7 @@
 #
 # resolver: ./custom-snapshot.yaml
 # resolver: https://example.com/snapshots/2018-01-01.yaml
-resolver: nightly-2021-03-13
+resolver: lts-18.25
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.
@@ -41,7 +41,7 @@ packages:
 #
 extra-deps:
   - pandoc-crossref-0.3.9.0
-  - hakyll-4.13.4.1
+  - hakyll-4.15.1.1
   - hakyll-images-1.0.1
   - roman-numerals-0.5.1.5
   - pandoc-citeproc-0.17.0.2
diff --git a/index.md b/index.md
index 5410b2139b31560389dc3f4f37a3431ecda1950e..cb2bccbad299ae0f242c43c85019d8a61ee55630 100644
--- a/index.md
+++ b/index.md
@@ -143,7 +143,7 @@ La chaîne *twitch* de mes cours se trouve sur <https://www.twitch.tv/omhepia>
 
 # Cours d'années précédentes
 
-# Programmation concurrente
+# Programmation concurrente (2019-2020)
 
 ## [Polycopié](concurrence/index.html), [git repo](https://githepia.hesge.ch/orestis.malaspin/cours_prog_conc)