diff --git a/9.0/buster/Dockerfile b/9.0/buster/Dockerfile
index e79d0fd..4767759 100644
--- a/9.0/buster/Dockerfile
+++ b/9.0/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM buildpack-deps:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # additional haskell specific deps
 RUN apt-get update && \
@@ -132,6 +132,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.0/slim-buster/Dockerfile b/9.0/slim-buster/Dockerfile
index e5632c9..d70fd8c 100644
--- a/9.0/slim-buster/Dockerfile
+++ b/9.0/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -148,6 +148,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.10/bullseye/Dockerfile b/9.10/bullseye/Dockerfile
index c6d2178..bad343b 100644
--- a/9.10/bullseye/Dockerfile
+++ b/9.10/bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -129,6 +129,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.10/buster/Dockerfile b/9.10/buster/Dockerfile
index f75805a..1a1ed08 100644
--- a/9.10/buster/Dockerfile
+++ b/9.10/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -129,6 +129,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.10/slim-bullseye/Dockerfile b/9.10/slim-bullseye/Dockerfile
index 1810f81..e62de66 100644
--- a/9.10/slim-bullseye/Dockerfile
+++ b/9.10/slim-bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -129,6 +129,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.10/slim-buster/Dockerfile b/9.10/slim-buster/Dockerfile
index 533ef62..5f83fb1 100644
--- a/9.10/slim-buster/Dockerfile
+++ b/9.10/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -131,6 +131,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.2/buster/Dockerfile b/9.2/buster/Dockerfile
index 2ec5220..ad468ab 100644
--- a/9.2/buster/Dockerfile
+++ b/9.2/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM buildpack-deps:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # additional haskell specific deps
 RUN apt-get update && \
@@ -115,6 +115,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.2/slim-buster/Dockerfile b/9.2/slim-buster/Dockerfile
index 7109ebb..9766768 100644
--- a/9.2/slim-buster/Dockerfile
+++ b/9.2/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -131,6 +131,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.4/buster/Dockerfile b/9.4/buster/Dockerfile
index 9a0c214..770756f 100644
--- a/9.4/buster/Dockerfile
+++ b/9.4/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM buildpack-deps:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # additional haskell specific deps
 RUN apt-get update && \
@@ -115,6 +115,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.4/slim-buster/Dockerfile b/9.4/slim-buster/Dockerfile
index 7d6b9bb..8ae51d1 100644
--- a/9.4/slim-buster/Dockerfile
+++ b/9.4/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -131,6 +131,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.6/bullseye/Dockerfile b/9.6/bullseye/Dockerfile
index fe9ad88..7826d93 100644
--- a/9.6/bullseye/Dockerfile
+++ b/9.6/bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -132,6 +132,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.6/buster/Dockerfile b/9.6/buster/Dockerfile
index 7edaaff..724b65c 100644
--- a/9.6/buster/Dockerfile
+++ b/9.6/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM buildpack-deps:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # additional haskell specific deps
 RUN apt-get update && \
@@ -115,6 +115,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.6/slim-bullseye/Dockerfile b/9.6/slim-bullseye/Dockerfile
index fbd978a..0941500 100644
--- a/9.6/slim-bullseye/Dockerfile
+++ b/9.6/slim-bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -134,6 +134,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.6/slim-buster/Dockerfile b/9.6/slim-buster/Dockerfile
index 66d2100..0022b69 100644
--- a/9.6/slim-buster/Dockerfile
+++ b/9.6/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -131,6 +131,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.8/bullseye/Dockerfile b/9.8/bullseye/Dockerfile
index a2f6194..bb8c3c9 100644
--- a/9.8/bullseye/Dockerfile
+++ b/9.8/bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -129,6 +129,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.8/buster/Dockerfile b/9.8/buster/Dockerfile
index aa4ff68..d484841 100644
--- a/9.8/buster/Dockerfile
+++ b/9.8/buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM buildpack-deps:buster
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # additional haskell specific deps
 RUN apt-get update && \
@@ -115,6 +115,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.8/slim-bullseye/Dockerfile b/9.8/slim-bullseye/Dockerfile
index 717dd9e..1f67aaa 100644
--- a/9.8/slim-bullseye/Dockerfile
+++ b/9.8/slim-bullseye/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bullseye-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -129,6 +129,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]
diff --git a/9.8/slim-buster/Dockerfile b/9.8/slim-buster/Dockerfile
index 336556b..a370fc7 100644
--- a/9.8/slim-buster/Dockerfile
+++ b/9.8/slim-buster/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:buster-slim
 
-ENV LANG C.UTF-8
+ENV LANG=C.UTF-8
 
 # common haskell + stack dependencies
 RUN apt-get update && \
@@ -131,6 +131,6 @@ RUN set -eux; \
     \
     "/opt/ghc/$GHC/bin/ghc" --version
 
-ENV PATH /root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
+ENV PATH=/root/.cabal/bin:/root/.local/bin:/opt/ghc/${GHC}/bin:$PATH
 
 CMD ["ghci"]