Fix build and update configuration

3 files changed, 6 insertions, 1 deletions

diff --git a/Gemfile b/Gemfile
index 46a8096..5190e36 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,6 +3,7 @@ source "https://rubygems.org"
 gem "jekyll"
 gem "webrick"
 gem "json"
+gem "erb"
 
 # https://github.com/rubyjs/mini_racer
 gem "mini_racer"
diff --git a/README.md b/README.md
index 75bb8fc..e9c112d 100644
--- a/README.md
+++ b/README.md
@@ -14,9 +14,13 @@ all its extensions needed by this website as listed in the `Gemfile`:
 
 ```sh
 $ bundle config set --local path .bundle
+$ bundle config build.posix-spawn --with-cflags="-Wno-incompatible-pointer-types"
 $ bundle install
 ```
 
+First try to run `bundle install` without changing any `CFLAGS`,
+it used to work like that, but not anymore as of mid-2024.
+
 Now you should be able to run a local development version with:
 
 ```sh
diff --git a/_config.yml b/_config.yml
index 5023f33..250ed0c 100644
--- a/_config.yml
+++ b/_config.yml
@@ -16,7 +16,7 @@ kramdown:
       macros:
         "\\Real": "\\mathop{\\mathrm{Re}}"
         "\\Imag": "\\mathop{\\mathrm{Im}}"
-        "\\pv": "\\:\\mathop{\\mathcal{P}}"
+        "\\pv": "\\:\\mathcal{P}\\!"
         "\\cross": "\\times"
         "\\va": "\\vec{\\mathbf{#1}}"
         "\\vb": "\\mathbf{#1}"