diff --git a/code/processes/converting-process/ft-keyword-extraction/java/nu/marginalia/keyword/DocumentPositionMapper.java b/code/processes/converting-process/ft-keyword-extraction/java/nu/marginalia/keyword/DocumentPositionMapper.java
index 0644cf76..ce7fb3b4 100644
--- a/code/processes/converting-process/ft-keyword-extraction/java/nu/marginalia/keyword/DocumentPositionMapper.java
+++ b/code/processes/converting-process/ft-keyword-extraction/java/nu/marginalia/keyword/DocumentPositionMapper.java
@@ -152,7 +152,10 @@ public class DocumentPositionMapper {
     }
 
     boolean matchesWordPattern(String s) {
-        // this function is an unrolled version of the regexp [\da-zA-Z]{1,15}([.\-_/:+*][\da-zA-Z]{1,10}){0,4}
+        if (s.length() > 48)
+            return false;
+
+        // this function is an unrolled version of the regexp [\da-zA-Z]{1,15}([.\-_/:+*][\da-zA-Z]{1,10}){0,8}
 
         String wordPartSeparator = ".-_/:+*";
 
@@ -169,7 +172,7 @@ public class DocumentPositionMapper {
         if (i == 0)
             return false;
 
-        for (int j = 0; j < 5; j++) {
+        for (int j = 0; j < 8; j++) {
             if (i == s.length()) return true;
 
             if (wordPartSeparator.indexOf(s.charAt(i)) < 0) {
diff --git a/code/processes/converting-process/ft-keyword-extraction/test/nu/marginalia/keyword/DocumentPositionMapperTest.java b/code/processes/converting-process/ft-keyword-extraction/test/nu/marginalia/keyword/DocumentPositionMapperTest.java
index a00dd3ae..533b0993 100644
--- a/code/processes/converting-process/ft-keyword-extraction/test/nu/marginalia/keyword/DocumentPositionMapperTest.java
+++ b/code/processes/converting-process/ft-keyword-extraction/test/nu/marginalia/keyword/DocumentPositionMapperTest.java
@@ -30,9 +30,11 @@ class DocumentPositionMapperTest {
         Assertions.assertFalse(positionMapper.matchesWordPattern("1234567890abcdef"));
 
         Assertions.assertTrue(positionMapper.matchesWordPattern("test-test-test-test-test"));
-        Assertions.assertFalse(positionMapper.matchesWordPattern("test-test-test-test-test-test"));
+        Assertions.assertFalse(positionMapper.matchesWordPattern("test-test-test-test-test-test-test-test-test"));
         Assertions.assertTrue(positionMapper.matchesWordPattern("192.168.1.100/24"));
         Assertions.assertTrue(positionMapper.matchesWordPattern("std::vector"));
+        Assertions.assertTrue(positionMapper.matchesWordPattern("std::vector::push_back"));
+
         Assertions.assertTrue(positionMapper.matchesWordPattern("c++"));
         Assertions.assertTrue(positionMapper.matchesWordPattern("m*a*s*h"));
         Assertions.assertFalse(positionMapper.matchesWordPattern("Stulpnagelstrasse"));