diff --git a/ChangeLog.md b/ChangeLog.md
index ca593c00e5..bb6918ff3c 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -71,6 +71,9 @@ Other enhancements:
   e.g. `stack unpack packagename`.
 * Git repos are shared across multiple projects. See
   [#3551](https://github.com/commercialhaskell/stack/issues/3551)
+* Use en_US.UTF-8 locale by default in pure Nix mode so programs won't
+  crash because of Unicode in their output
+  [#4095](https://github.com/commercialhaskell/stack/issues/4095)
 
 Bug fixes:
 
diff --git a/src/Stack/Nix.hs b/src/Stack/Nix.hs
index ea4cdbe657..6c0b7536d6 100644
--- a/src/Stack/Nix.hs
+++ b/src/Stack/Nix.hs
@@ -100,6 +100,8 @@ runShellAndExit mprojectRoot getCompilerVersion getCmdArgs = do
                               ,"LD_LIBRARY_PATH = libPath;"  -- LD_LIBRARY_PATH is set because for now it's
                                -- needed by builds using Template Haskell
                               ,"STACK_IN_NIX_EXTRA_ARGS = stackExtraArgs; "
+                               -- overriding default locale so Unicode output using base won't be broken
+                              ,"LANG=\"en_US.UTF-8\";"
                               ,"} \"\""]]
                     -- glibcLocales is necessary on Linux to avoid warnings about GHC being incapable to set the locale.
          fullArgs = concat [if pureShell then ["--pure"] else []
diff --git a/test/integration/tests/4095-utf8-pure-nix/Main.hs b/test/integration/tests/4095-utf8-pure-nix/Main.hs
new file mode 100644
index 0000000000..f8999ddc47
--- /dev/null
+++ b/test/integration/tests/4095-utf8-pure-nix/Main.hs
@@ -0,0 +1,6 @@
+import StackTest
+
+main :: IO ()
+main = do
+  stack ["build", "--nix-pure"]
+  stack ["exec", "--nix-pure", "ShowUnicode"]
diff --git a/test/integration/tests/4095-utf8-pure-nix/files/ShowUnicode.hs b/test/integration/tests/4095-utf8-pure-nix/files/ShowUnicode.hs
new file mode 100644
index 0000000000..91011a6576
--- /dev/null
+++ b/test/integration/tests/4095-utf8-pure-nix/files/ShowUnicode.hs
@@ -0,0 +1,5 @@
+import System.IO (stdout)
+import Text.Printf (hPrintf)
+
+main :: IO ()
+main = hPrintf stdout "平和"
diff --git a/test/integration/tests/4095-utf8-pure-nix/files/package.yaml b/test/integration/tests/4095-utf8-pure-nix/files/package.yaml
new file mode 100644
index 0000000000..5ee0230a5f
--- /dev/null
+++ b/test/integration/tests/4095-utf8-pure-nix/files/package.yaml
@@ -0,0 +1,4 @@
+executables:
+ ShowUnicode:
+  dependencies: [base]
+  main: ShowUnicode.hs
diff --git a/test/integration/tests/4095-utf8-pure-nix/files/stack.yaml b/test/integration/tests/4095-utf8-pure-nix/files/stack.yaml
new file mode 100644
index 0000000000..9673b65de3
--- /dev/null
+++ b/test/integration/tests/4095-utf8-pure-nix/files/stack.yaml
@@ -0,0 +1 @@
+resolver: lts-11.19