diff --git a/CHANGELOG.md b/CHANGELOG.md
index a90fc02..06c14aa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 ## v183 (2020-10-12)
 
 - Add support for Heroku-20 (#968).
+- Fix metric names for metrics emitted within `sub_env` (#1099).
 
 ## v182 (2020-10-06)
 
diff --git a/bin/compile b/bin/compile
index 2054a29..c81e97b 100755
--- a/bin/compile
+++ b/bin/compile
@@ -18,7 +18,7 @@ set -eo pipefail
 # Boostrap the Buildpack Standard Library.
 # Disable unused env var warning since shellcheck doesn't know about the stdlib.
 # shellcheck disable=2034
-BPLOG_PREFIX="buildpack.python"
+export BPLOG_PREFIX="buildpack.python"
 export BUILDPACK_LOG_FILE=${BUILDPACK_LOG_FILE:-/dev/null}
 
 [ "$BUILDPACK_XTRACE" ] && set -o xtrace
diff --git a/test/run-features b/test/run-features
index a873788..7496854 100755
--- a/test/run-features
+++ b/test/run-features
@@ -116,6 +116,7 @@ testHooks() {
   local expected_env_vars=(
     _
     BIN_DIR
+    BPLOG_PREFIX
     BUILD_DIR
     BUILDPACK_LOG_FILE
     CACHE_DIR