diff --git a/.github/workflows/subdoc.yml b/.github/workflows/subdoc.yml
index 8f149b697..59403c814 100644
--- a/.github/workflows/subdoc.yml
+++ b/.github/workflows/subdoc.yml
@@ -172,6 +172,7 @@ jobs:
             --project-name Subspace \
             --remove-source-path-prefix $PWD \
             --add-source-path-prefix ${source_url} \
+            --source-path-line-prefix L \
             /home/runner/work/subspace/subspace/sus
 
       - name: Deploy
diff --git a/.github/workflows/try.yml b/.github/workflows/try.yml
index 6e8543ccf..ba5b8ff9e 100644
--- a/.github/workflows/try.yml
+++ b/.github/workflows/try.yml
@@ -420,6 +420,7 @@ jobs:
             --project-name Subspace \
             --remove-source-path-prefix $PWD \
             --add-source-path-prefix ${source_url} \
+            --source-path-line-prefix L \
             /home/runner/work/subspace/subspace/sus
 
   bench:
diff --git a/subdoc/lib/database.h b/subdoc/lib/database.h
index e884cbc96..8fa479b61 100644
--- a/subdoc/lib/database.h
+++ b/subdoc/lib/database.h
@@ -69,7 +69,7 @@ struct SourceLink {
   };
   Quality quality;
   std::string file_path;
-  u32 line;
+  std::string line;
 
   friend std::weak_ordering operator<=>(const SourceLink& lhs,
                                         const SourceLink& rhs) noexcept {
diff --git a/subdoc/lib/run_options.h b/subdoc/lib/run_options.h
index e17e099b0..2417e769e 100644
--- a/subdoc/lib/run_options.h
+++ b/subdoc/lib/run_options.h
@@ -49,6 +49,10 @@ struct RunOptions {
     macro_prefixes = sus::move(prefixes);
     return sus::move(*this);
   }
+  RunOptions set_generate_source_links(bool gen) && {
+    generate_source_links = gen;
+    return sus::move(*this);
+  }
   RunOptions set_remove_path_prefix(sus::Option<std::string> prefix) && {
     remove_path_prefix = sus::move(prefix);
     return sus::move(*this);
@@ -57,6 +61,10 @@ struct RunOptions {
     add_path_prefix = sus::move(prefix);
     return sus::move(*this);
   }
+  RunOptions set_source_line_prefix(sus::Option<std::string> prefix) && {
+    source_line_prefix = sus::move(prefix);
+    return sus::move(*this);
+  }
 
   /// Whether to print progress while collecting documentation from souce files.
   bool show_progress = true;
@@ -84,6 +92,9 @@ struct RunOptions {
   /// A prefix to add to all paths in source links, after removing the prefix
   /// specified by `remove_path_prefix`.
   sus::Option<std::string> add_path_prefix;
+  /// A prefix to add to the source code line number html fragment. Github uses
+  /// an `L` as its prefix.
+  sus::Option<std::string> source_line_prefix;
 };
 
 }  // namespace subdoc
diff --git a/subdoc/lib/visit.cc b/subdoc/lib/visit.cc
index 08053387d..cd746f55e 100644
--- a/subdoc/lib/visit.cc
+++ b/subdoc/lib/visit.cc
@@ -1583,9 +1583,14 @@ class Visitor : public clang::RecursiveASTVisitor<Visitor> {
       std::replace(canonical_path.begin(), canonical_path.end(), '\\', '/');
 
       if (cx_.options.remove_path_prefix.is_some()) {
-        const auto& prefix = cx_.options.remove_path_prefix.as_value();
-        if (canonical_path.starts_with(prefix)) {
-          canonical_path = canonical_path.substr(prefix.size());
+        // Canonicalize the path to use `/` instead of `\`.
+        std::string canonical_prefix =
+            sus::clone(cx_.options.remove_path_prefix.as_value());
+        std::replace(canonical_prefix.begin(), canonical_prefix.end(), '\\',
+                     '/');
+
+        if (canonical_path.starts_with(canonical_prefix)) {
+          canonical_path = canonical_path.substr(canonical_prefix.size());
           if (canonical_path.starts_with("/"))
             canonical_path = canonical_path.substr(1u);
         }
@@ -1596,10 +1601,16 @@ class Visitor : public clang::RecursiveASTVisitor<Visitor> {
         canonical_path.insert(0u, prefix);
       }
 
+      std::ostringstream line;
+      if (cx_.options.source_line_prefix.is_some()) {
+        line << cx_.options.source_line_prefix.as_value();
+      }
+      line << sm.getLineNumber(sm.getFileID(loc), sm.getFileOffset(loc));
+
       auto link = sus::Option<SourceLink>(SourceLink{
           .quality = quality,
           .file_path = sus::move(canonical_path),
-          .line = sm.getLineNumber(sm.getFileID(loc), sm.getFileOffset(loc)),
+          .line = sus::move(line).str(),
       });
       if (link > e.source_link) e.source_link = sus::move(link);
     }
diff --git a/subdoc/subdoc_main.cc b/subdoc/subdoc_main.cc
index 179cc7e03..eff62baf3 100644
--- a/subdoc/subdoc_main.cc
+++ b/subdoc/subdoc_main.cc
@@ -118,6 +118,12 @@ int main(int argc, const char** argv) {
           "specified by `--remove-source-path-prefix` is removed."),
       llvm::cl::cat(option_category));
 
+  llvm::cl::opt<std::string> option_source_line_prefix(
+      "source-path-line-prefix",
+      llvm::cl::desc("A prefix to add to the line number on all source code "
+                     "links. Github uses an `L` as its prefix."),
+      llvm::cl::cat(option_category));
+
   llvm::cl::opt<bool> option_no_source_links(
       "no-source-links",
       llvm::cl::desc("Avoid generating links to source code."),
@@ -228,14 +234,16 @@ int main(int argc, const char** argv) {
           .collect<sus::Vec<std::string>>();
   run_options.generate_source_links = !option_no_source_links.getValue();
   if (option_remove_path_prefix.getNumOccurrences() > 0) {
-    // Canonicalize the path to use `/` instead of `\`.
-    std::string canonical_path = option_remove_path_prefix.getValue();
-    std::replace(canonical_path.begin(), canonical_path.end(), '\\', '/');
-    run_options.remove_path_prefix = sus::some(sus::move(canonical_path));
+    run_options.remove_path_prefix =
+        sus::some(sus::move(option_remove_path_prefix.getValue()));
   }
   if (option_add_path_prefix.getNumOccurrences() > 0) {
     run_options.add_path_prefix = sus::some(option_add_path_prefix.getValue());
   }
+  if (option_source_line_prefix.getNumOccurrences() > 0) {
+    run_options.source_line_prefix =
+        sus::some(option_source_line_prefix.getValue());
+  }
 
   auto fs = llvm::vfs::getRealFileSystem();
   auto result = subdoc::run_files(comp_db, sus::move(run_against_files),
diff --git a/subdoc/tests/aliases_unittest.cc b/subdoc/tests/aliases_unittest.cc
index 3b4e260c4..02d2d58d7 100644
--- a/subdoc/tests/aliases_unittest.cc
+++ b/subdoc/tests/aliases_unittest.cc
@@ -35,13 +35,13 @@ TEST_F(SubDocTest, AliasUsingStruct) {
     auto& e = db.find_alias_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 8u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "8");
   }
   {
     auto& e = db.find_alias_comment("10:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
   }
 }
 
@@ -66,13 +66,13 @@ TEST_F(SubDocTest, AliasUsingConcept) {
     auto& e = db.find_alias_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 8u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "8");
   }
   {
     auto& e = db.find_alias_comment("10:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
   }
 }
 
@@ -98,7 +98,7 @@ TEST_F(SubDocTest, AliasUsingMethod) {
   auto& e = db.find_alias_comment("10:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
 }
 
 TEST_F(SubDocTest, AliasUsingEnumInNamespace) {
@@ -114,7 +114,7 @@ TEST_F(SubDocTest, AliasUsingEnumInNamespace) {
   auto& e = db.find_alias_comment("3:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, DISABLED_AliasUsingEnum) {
@@ -141,13 +141,13 @@ TEST_F(SubDocTest, DISABLED_AliasUsingEnum) {
     auto& e = db.find_alias_comment("8:7").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 9u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "9");
   }
   {
     auto& e = db.find_alias_comment("13:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 14u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "14");
   }
 }
 
@@ -185,13 +185,13 @@ TEST_F(SubDocTest, AliasNamedTypeInNamespace) {
     auto& e = db.find_alias_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 8u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "8");
   }
   {
     auto& e = db.find_alias_comment("10:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
   }
 }
 
@@ -213,7 +213,7 @@ TEST_F(SubDocTest, AliasNamedTypeInRecord) {
     auto& e = db.find_alias_comment("7:7").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 8u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "8");
   }
 }
 
@@ -233,6 +233,6 @@ TEST_F(SubDocTest, AliasUsingVariable) {
     auto& e = db.find_alias_comment("6:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 7u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "7");
   }
 }
diff --git a/subdoc/tests/fields_unittest.cc b/subdoc/tests/fields_unittest.cc
index 48975d812..1765bf4f9 100644
--- a/subdoc/tests/fields_unittest.cc
+++ b/subdoc/tests/fields_unittest.cc
@@ -27,7 +27,7 @@ TEST_F(SubDocTest, Field) {
   auto& e = db.find_field_comment("3:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, StaticField) {
@@ -43,7 +43,7 @@ TEST_F(SubDocTest, StaticField) {
   auto& e = db.find_field_comment("3:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, StaticFieldSplit) {
@@ -61,7 +61,7 @@ TEST_F(SubDocTest, StaticFieldSplit) {
   auto& e = db.find_field_comment("3:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 7u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "7");
 }
 
 TEST_F(SubDocTest, PrivateField) {
@@ -133,12 +133,12 @@ TEST_F(SubDocTest, Variables) {
     auto& e = db.find_variable_comment("2:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
   }
   {
     auto& e = db.find_variable_comment("5:7").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 6u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "6");
   }
 }
diff --git a/subdoc/tests/functions_unittest.cc b/subdoc/tests/functions_unittest.cc
index a03914239..8f0aa5651 100644
--- a/subdoc/tests/functions_unittest.cc
+++ b/subdoc/tests/functions_unittest.cc
@@ -26,7 +26,7 @@ TEST_F(SubDocTest, Function) {
   auto& e = db.find_function_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
 }
 
 TEST_F(SubDocTest, FunctionOverloads) {
@@ -47,13 +47,13 @@ TEST_F(SubDocTest, FunctionOverloads) {
     auto& e = db.find_function_comment("2:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
   }
   {
     auto& e = db.find_function_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 8u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "8");
   }
 }
 
@@ -80,13 +80,13 @@ TEST_F(SubDocTest, FunctionOverloadsNoMerge) {
     auto& e = db.find_function_comment("2:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 6u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "6");
   }
   {
     auto& e = db.find_function_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
   }
 }
 
@@ -109,13 +109,13 @@ TEST_F(SubDocTest, FunctionOverloadsMerge) {
     auto& e = db.find_function_comment("2:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
   }
   {
     auto& e = db.find_function_comment("7:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 9u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "9");
   }
 }
 
@@ -205,7 +205,7 @@ TEST_F(SubDocTest, ForwardDeclDocumented) {
   auto& e = db.find_function_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, ForwardDeclUndocumented) {
@@ -222,7 +222,7 @@ TEST_F(SubDocTest, ForwardDeclUndocumented) {
   auto& e = db.find_function_comment("3:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, FunctionInNamedNamespace) {
@@ -239,7 +239,7 @@ TEST_F(SubDocTest, FunctionInNamedNamespace) {
   auto& e = db.find_function_comment("3:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, FunctionInAnonymousNamespace) {
@@ -294,19 +294,19 @@ TEST_F(SubDocTest, FunctionFriend) {
     auto& e = db.find_function_comment("3:7").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
   }
   {
     auto& e = db.find_function_comment("7:7").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 11u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "11");
   }
   {
     auto& e = db.find_function_comment("13:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 14u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "14");
   }
 }
 
diff --git a/subdoc/tests/macros_unittest.cc b/subdoc/tests/macros_unittest.cc
index 288ab5234..2aedfeb0c 100644
--- a/subdoc/tests/macros_unittest.cc
+++ b/subdoc/tests/macros_unittest.cc
@@ -35,7 +35,7 @@ TEST_F(SubDocTest, MacroFunction) {
   auto& e = db.find_function_comment("3:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, MacroClass) {
@@ -109,7 +109,7 @@ TEST_F(SubDocTest, MacroNamesField) {
   auto& e = db.find_field_comment("4:9").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 5u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "5");
 }
 
 TEST_F(SubDocTest, MacroModName) {
@@ -126,7 +126,7 @@ TEST_F(SubDocTest, MacroModName) {
   auto& e = db.find_record_comment("4:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 5u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "5");
 }
 
 TEST_F(SubDocTest, MacroMultilineComment) {
@@ -185,5 +185,5 @@ TEST_F(SubDocTest, Macro) {
   auto& e = db.find_macro_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
 }
diff --git a/subdoc/tests/namespaces_unittest.cc b/subdoc/tests/namespaces_unittest.cc
index 4c0f9369a..d8c03eaa7 100644
--- a/subdoc/tests/namespaces_unittest.cc
+++ b/subdoc/tests/namespaces_unittest.cc
@@ -102,7 +102,7 @@ TEST_F(SubDocTest, NamespaceComment) {
   auto& e = db.find_namespace_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
 }
 
 TEST_F(SubDocTest, NestedNamespaceComment) {
@@ -119,7 +119,7 @@ TEST_F(SubDocTest, NestedNamespaceComment) {
   auto& e = db.find_namespace_comment("3:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, NamespaceDotsComment) {
diff --git a/subdoc/tests/records_unittest.cc b/subdoc/tests/records_unittest.cc
index e7f397aaa..e96d8fb51 100644
--- a/subdoc/tests/records_unittest.cc
+++ b/subdoc/tests/records_unittest.cc
@@ -26,7 +26,7 @@ TEST_F(SubDocTest, Struct) {
   auto& e = db.find_record_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
 }
 
 TEST_F(SubDocTest, ForwardStruct) {
@@ -55,7 +55,7 @@ TEST_F(SubDocTest, TemplateStruct) {
   auto& e = db.find_record_comment("2:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, TemplateStructSpecialization) {
@@ -88,7 +88,7 @@ TEST_F(SubDocTest, StructInNamedNamespace) {
   auto& e = db.find_record_comment("3:5").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 4u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "4");
 }
 
 TEST_F(SubDocTest, StructInPrivateNamespace) {
@@ -147,7 +147,7 @@ TEST_F(SubDocTest, NestedStruct) {
   auto& e = db.find_record_comment("4:7").unwrap();
   ASSERT_TRUE(e.source_link.is_some());
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 5u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "5");
 }
 
 TEST_F(SubDocTest, PrivateStruct) {
@@ -198,12 +198,12 @@ TEST_F(SubDocTest, AnonStruct) {
     auto& e = db.find_record_comment("2:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
   }
   {
     auto& e = db.find_record_comment("4:5").unwrap();
     ASSERT_TRUE(e.source_link.is_some());
     EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "test.cc");
-    EXPECT_EQ(e.source_link.as_ref().unwrap().line, 5u);
+    EXPECT_EQ(e.source_link.as_ref().unwrap().line, "5");
   }
 }
diff --git a/subdoc/tests/source_link_unittest.cc b/subdoc/tests/source_link_unittest.cc
index e99050e81..b56dff103 100644
--- a/subdoc/tests/source_link_unittest.cc
+++ b/subdoc/tests/source_link_unittest.cc
@@ -38,7 +38,34 @@ TEST_F(SubDocTest, SourceLinkFilePath) {
 #else
   EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "/path/to/test.cc");
 #endif
-  EXPECT_EQ(e.source_link.as_ref().unwrap().line, 3u);
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "3");
+}
+
+TEST_F(SubDocTest, SourceLinkPrefixes) {
+#ifdef _MSC_VER
+  const char PATH[] = "C:\\path\\to\\test.cc";
+  const char REMOVE[] = "C:\\path";
+#else
+  const char PATH[] = "/path/to/test.cc";
+  const char REMOVE[] = "/path";
+#endif
+
+  auto options = subdoc::RunOptions()
+                     .set_show_progress(false)
+                     .set_remove_path_prefix(sus::some(REMOVE))
+                     .set_add_path_prefix(sus::some("/things"))
+                     .set_source_line_prefix(sus::some("L"));
+  auto result = run_code_with_options(options, PATH, R"(
+    /// Comment headline 1
+    int i;
+  )");
+  ASSERT_TRUE(result.is_ok());
+  subdoc::Database db = sus::move(result).unwrap();
+  ASSERT_TRUE(has_variable_comment(db, "2:5", "<p>Comment headline 1</p>"));
+  auto& e = db.find_variable_comment("2:5").unwrap();
+  ASSERT_TRUE(e.source_link.is_some());
+  EXPECT_EQ(e.source_link.as_ref().unwrap().file_path, "/things/to/test.cc");
+  EXPECT_EQ(e.source_link.as_ref().unwrap().line, "L3");
 }
 
 }  // namespace
diff --git a/tools/run_subdoc.bat b/tools/run_subdoc.bat
index 036aaf1f6..35b3ffab7 100644
--- a/tools/run_subdoc.bat
+++ b/tools/run_subdoc.bat
@@ -15,4 +15,5 @@ out\subdoc\subdoc -p out --out docs ^
     --ignore-bad-code-links ^
     --remove-source-path-prefix %cd% ^
     --add-source-path-prefix .. ^
+    --source-path-line-prefix L ^
     subspace/sus/num/uptr_uni reverse_uni
diff --git a/tools/run_subdoc.sh b/tools/run_subdoc.sh
index 98f58756a..1fa0682e7 100755
--- a/tools/run_subdoc.sh
+++ b/tools/run_subdoc.sh
@@ -17,4 +17,5 @@ out/subdoc/subdoc -p out --out docs \
     --ignore-bad-code-links \
     --remove-source-path-prefix $PWD \
     --add-source-path-prefix .. \
+    --source-path-line-prefix L \
    i8_unittest $*