diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 589a447..5043566 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -1,7 +1,6 @@
 name: Check
 on:
-  pull_request_target:
-    types: [edited, opened, reopened, synchronize]
+  pull_request:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
@@ -39,21 +38,29 @@ jobs:
           if [[ $INPUT_TITLE =~ \[(.*)\] ]]; then
               NEW_BUMP_TYPE="${BASH_REMATCH[1]}"
           else
-              echo "Bump type not found" >&2; exit 1;
-          fi
-          if [[ "$NEW_BUMP_TYPE" == "none" ]]; then
-            echo "Bump type none, skip compare"
-            exit 0
+              echo "Bump type not found. Please specify bump type in your pull request title. Example: [patch] fix very annoying bug." >&2; exit 1;
           fi
+
           git fetch
+
           base_branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}
           target_branch=${{ github.event.pull_request.base.ref }}
+
           chmod +x ./scripts/helpers/build_and_dump.sh
           chmod +x ./scripts/helpers/abi_comparator.sh
+
           base_tmp_dir=$(mktemp -d)
-          base_abi_dump_path=$(./scripts/helpers/build_and_dump.sh $base_tmp_dir)
-          git checkout -b target_branch
+          IFS=$'\n' read -r -d '' base_abi_dump_path base_api_dump_path < <(./scripts/helpers/build_and_dump.sh $base_tmp_dir)
+
+          git checkout $target_branch
           target_tmp_dir=$(mktemp -d)
-          target_abi_dump_path=$(./scripts/helpers/build_and_dump.sh $target_tmp_dir)
-          ./scripts/helpers/abi_comparator.sh $base_tmp_dir $target_abi_dump_path $base_abi_dump_path $NEW_BUMP_TYPE
-          
+          IFS=$'\n' read -r -d '' target_abi_dump_path target_api_dump_path < <(./scripts/helpers/build_and_dump.sh $target_tmp_dir)
+
+          git checkout $base_branch
+
+          sources_changed=false
+          if git diff --name-only $target_branch $base_branch | grep -q "^Sources/ProjectDescription/"; then
+            sources_changed=true
+          fi
+
+          ./scripts/helpers/abi_comparator.sh $base_tmp_dir $target_abi_dump_path $base_abi_dump_path $target_api_dump_path $base_api_dump_path $sources_changed $NEW_BUMP_TYPE
diff --git a/scripts/helpers/abi_comparator.sh b/scripts/helpers/abi_comparator.sh
index eb9df0c..6dadeb4 100755
--- a/scripts/helpers/abi_comparator.sh
+++ b/scripts/helpers/abi_comparator.sh
@@ -11,10 +11,12 @@ log_info() { echo "ℹ️ $1"; }
 # Input
 
 TMP_DIR=$1
-PREV_DUMP_PATH=$2
+PREV_ABI_DUMP_PATH=$2
 CURRENT_ABI_DUMP_PATH=$3
-BUMP_TYPE=$4
-
+PREV_API_DUMP_PATH=$4
+CURRENT_API_DUMP_PATH=$5
+SOURCES_CHANGED=$6
+BUMP_TYPE=$7
 
 get_priority() {
     case "$1" in
@@ -33,71 +35,85 @@ prepare_dump() {
     jq 'walk(if type == "object" then del(.deprecated) else . end)' "$input_path" > "$output_path"
 }
 
-bump_type_from_report() {
-    local report_path=$1
-    local bump_type=$2
-    local suitable_bump="patch"
-
-    while IFS= read -r line; do
-        # Skip system messages
-        [[ $line =~ ^[0-9]+\ (error|warning)s?\ generated\. ]] && continue
-        [[ $line =~ xcodebuild\[.*\]\ Requested\ but\ did\ not\ find\ extension\ point ]] && continue
-        [[ -z "$line" ]] && continue
-
-        # Parse: <file>:<line>: <type>: <message>
-        if [[ $line =~ :([0-9]+):\ (error|warning):\ (.+)$ ]]; then
-            local type="${BASH_REMATCH[2]}"
-            local message="${BASH_REMATCH[3]}"
-
-            if [[ "$type" == "warning" ]]; then
-                echo "⚠️  $message"
-            elif [[ "$type" == "error" ]]; then
-                echo "⛔️ $message"
-                suitable_bump="minor"
-            fi
-        else
-            log_error "Invalid output line: $line"
-        fi
-    done < $report_path
-
-    # Validate real and expected bump types
-    weight_bump_type=$(get_priority "$bump_type")
-    weight_suitable_bump=$(get_priority "$suitable_bump")
-    if (( weight_bump_type < weight_suitable_bump )); then
-        log_error "Wrong bump_type '$bump_type' specified. Suitable is '$suitable_bump'."
-    else
-        log_success "Suitable bump_type is '$suitable_bump', specified is '$bump_type'"
-    fi
+validate_bump_type() {
+	local abi_report_path=$1
+	local api_report_path=$2
+	local bump_type=$3
+	local suitable_bump="none"
+
+	if [ $SOURCES_CHANGED = true ]; then
+		suitable_bump="patch"
+	fi
+
+	while IFS= read -r line; do
+		# Skip system messages
+		[[ $line =~ ^[0-9]+\ (error|warning)s?\ generated\. ]] && continue
+		[[ $line =~ xcodebuild\[.*\]\ Requested\ but\ did\ not\ find\ extension\ point ]] && continue
+		[[ -z "$line" ]] && continue
+
+		# Parse: <file>:<line>: <type>: <message>
+		if [[ $line =~ :([0-9]+):\ (error|warning):\ (.+)$ ]]; then
+			local type="${BASH_REMATCH[2]}"
+			local message="${BASH_REMATCH[3]}"
+
+			if [[ "$type" == "warning" ]]; then
+				echo "⚠️  $message"
+			elif [[ "$type" == "error" ]]; then
+				echo "⛔️ $message"
+				suitable_bump="minor"
+			fi
+		else
+			log_error "Invalid output line: $line"
+		fi
+	done < $abi_report_path
+
+	#TODO: Implement API comparison
+
+	# Validate real and expected bump types
+	weight_bump_type=$(get_priority "$bump_type")
+	weight_suitable_bump=$(get_priority "$suitable_bump")
+	if (( weight_bump_type < weight_suitable_bump )); then
+		log_error "Wrong bump_type '$bump_type' specified. Suitable is '$suitable_bump'."
+	else
+		log_success "Suitable bump_type is '$suitable_bump', specified is '$bump_type'"
+	fi
 }
 
-if [[ -f "$FILE_VAR" ]]; then
-    echo "$FILE_VAR exists and is a regular file."
-else
-    echo "$FILE_VAR is not a regular file or does not exist."
-fi
-
-# Loading an old dump
-
 # Prepare old dump (remove all "deprecated")
-log_info "Prepare old dump"
-old_prepared_path="$TMP_DIR/old-prepared.json"
-prepare_dump "$PREV_DUMP_PATH" "$old_prepared_path"
-log_success "Dump prepared"
+# log_info "Prepare old dump"
+# old_prepared_path="$TMP_DIR/old-prepared.json"
+# prepare_dump "$PREV_ABI_DUMP_PATH" "$old_prepared_path"
+# log_success "Dump prepared"
 
 # ABI compare
-report_path="$TMP_DIR/breakage-report.log"
+abi_report_path="$TMP_DIR/abi_breakage-report.log"
 log_info "Comparing ABI..."
 
-# WARNING: not work on x86_64
+# WARNING: does not work for x86_64
 set +e # Allow swift-api-digester to return a non-zero code
 xcrun swift-api-digester \
     -diagnose-sdk \
-    -input-paths "$old_prepared_path" \
+    -input-paths "$PREV_ABI_DUMP_PATH" \
     -input-paths "$CURRENT_ABI_DUMP_PATH" \
     -disable-fail-on-error \
     -compiler-style-diags \
     -abi \
-    -error-on-abi-breakage 2> "$report_path"
+    -error-on-abi-breakage 2> "$abi_report_path"
+set -e
+
+# API compare
+api_report_path="$TMP_DIR/api_breakage-report.log"
+log_info "Comparing API..."
+
+# WARNING: does not work for x86_64
+set +e # Allow swift-api-digester to return a non-zero code
+xcrun swift-api-digester \
+    -diagnose-sdk \
+    -input-paths "$PREV_API_DUMP_PATH" \
+    -input-paths "$CURRENT_API_DUMP_PATH" \
+    -disable-fail-on-error \
+    -compiler-style-diags \
+    -error-on-abi-breakage 2> "$api_report_path"
 set -e
 
-bump_type_from_report $report_path $BUMP_TYPE
+validate_bump_type $abi_report_path $api_report_path $BUMP_TYPE
diff --git a/scripts/helpers/build_and_dump.sh b/scripts/helpers/build_and_dump.sh
index 8bcd599..4a96ed2 100755
--- a/scripts/helpers/build_and_dump.sh
+++ b/scripts/helpers/build_and_dump.sh
@@ -12,7 +12,8 @@ tmp_build_dir="$tmp_dir/build"
 module_name="ProjectDescription"
 configuration="Release"
 framework_path="${tmp_build_dir}/${configuration}"
-output_path="$tmp_dir/current-abi.json"
+output_abi_path="$tmp_dir/current-abi.json"
+output_api_path="$tmp_dir/current-api.json"
 
 xcrun xcodebuild -scheme ProjectDescription \
     -configuration "$configuration" \
@@ -37,6 +38,21 @@ xcrun swift-api-digester \
         -abi \
         -sdk "$sdk_path" \
         -target "arm64-apple-macos" \
-        -o "$output_path"
+        -o "$output_abi_path"
 
-echo $output_path
\ No newline at end of file
+xcrun swift-api-digester \
+        -dump-sdk \
+        -abort-on-module-fail \
+        -module "$module_name" \
+        -use-interface-for-module "$module_name" \
+        -F "$framework_path" \
+        -I "$framework_path" \
+        -avoid-tool-args \
+        -avoid-location \
+        -sdk "$sdk_path" \
+        -target "arm64-apple-macos" \
+        -o "$output_api_path"
+
+echo $output_abi_path
+echo $output_api_path
+printf '\0'