diff --git a/fcore/app-with.sml b/fcore/app-with.sml
index 68163da..1a5c1b1 100644
--- a/fcore/app-with.sml
+++ b/fcore/app-with.sml
@@ -98,4 +98,28 @@ struct
       , startLine = startLine
       }
     end
+
+  fun searchListAndBuffer (app: app_type, newSearchList, newBuffer) =
+    let
+      val
+        { searchList = _
+        , buffer = _
+        , mode
+        , searchString
+        , cursorIdx
+        , windowWidth
+        , windowHeight
+        , startLine
+        } = app
+    in
+      { searchList = newSearchList
+      , buffer = newBuffer
+      , mode = mode
+      , searchString = searchString
+      , cursorIdx = cursorIdx
+      , windowWidth = windowWidth
+      , windowHeight = windowHeight
+      , startLine = startLine
+      }
+    end
 end
diff --git a/fcore/build-search-list.sml b/fcore/build-search-list.sml
new file mode 100644
index 0000000..04d6952
--- /dev/null
+++ b/fcore/build-search-list.sml
@@ -0,0 +1,81 @@
+structure BuildSearchList =
+struct
+  fun helpNextMatch (idx, hd, tl, absIdx, searchString, matchedChrs) =
+    if idx = String.size hd then
+      case tl of
+        tlhd :: tltl =>
+          helpNextMatch (0, tlhd, tltl, absIdx, searchString, matchedChrs)
+      | [] => 
+          NONE
+    else
+      let
+        val hdChr = String.sub (hd, idx)
+        val searchChr = String.sub (searchString, matchedChrs)
+      in
+        if hdChr = searchChr then
+          if matchedChrs + 1 = String.size searchString then
+            let
+              val matchedIdx = absIdx - String.size searchString - 1
+            in
+              SOME matchedIdx
+            end
+          else
+            helpNextMatch 
+              (idx + 1, hd, tl, absIdx + 1, searchString, matchedChrs + 1)
+        else
+          helpNextMatch (idx + 1, hd, tl, absIdx + 1, searchString, 0)
+      end
+
+  fun nextMatch (bufferIdx, absIdx, rightStrings, searchString) =
+    case rightStrings of
+      hd :: tl =>
+        let 
+          val strIdx = absIdx - bufferIdx
+        in
+          if strIdx < String.size hd then
+            helpNextMatch (strIdx, hd, tl, absIdx, searchString, 0)
+          else
+            (case tl of
+              tlhd :: tltl =>
+                let
+                  val strIdx = strIdx - String.size hd
+                in
+                  helpNextMatch (strIdx, tlhd, tltl, absIdx, searchString, 0)
+                end
+            | [] => NONE)
+        end
+    | [] => NONE
+
+  fun helpBuild (app, origIdx, absIdx, buffer, searchString, searchList) =
+    let
+      val buffer = LineGap.goToIdx (absIdx, buffer)
+      val {idx = bufferIdx, rightStrings, ...} = buffer
+    in
+      case nextMatch (bufferIdx, absIdx, rightStrings, searchString) of
+        SOME matchedIdx =>
+          let
+            val searchList = SearchList.append (matchedIdx, searchList)
+          in
+            helpBuild 
+              (app, origIdx, matchedIdx, buffer, searchString, searchList)
+          end
+      | NONE =>
+          let
+            val buffer = LineGap.goToIdx (origIdx, buffer)
+            val searchList = SearchList.goToNum (origIdx, searchList)
+          in
+            AppWith.searchListAndBuffer (app, searchList, buffer)
+          end
+    end
+
+  fun build (app, cursorIdx, buffer, searchString) =
+    if String.size searchString > 0 then
+      let
+        val buffer = LineGap.goToStart buffer
+      in
+        helpBuild 
+          (app, cursorIdx, 0, buffer, searchString, SearchList.empty)
+      end
+    else
+      app
+end
diff --git a/fcore/search-list.sml b/fcore/search-list.sml
index cf38b57..c2f7fac 100644
--- a/fcore/search-list.sml
+++ b/fcore/search-list.sml
@@ -2,8 +2,12 @@ signature SEARCH_LIST =
 sig
   type t = {left: int vector list, right: int vector list}
   val empty: t
+
   val insert: int * t -> t
+  val append: int * t -> t
   val delete: int * int * t -> t
+
+  val goToNum: int * t -> t
   val mapFromNum: int * int * t -> t
 end
 
@@ -148,6 +152,13 @@ struct
         else insLeft (new, left, right)
     | [] => insLeft (new, left, right)
 
+  fun helpAppend (new, left, right) =
+    case right of
+      hd :: tl => helpAppend (new, joinEndOfLeft (hd, left), tl)
+    | [] => {left = joinEndOfLeft (Vector.fromList [new], left), right = right}
+
+  fun append (new, {left, right}: t) = helpAppend (new, left, right)
+
   fun helpGoToNumLeft (num, left, right) =
     case left of
       hd :: tl =>
diff --git a/shf b/shf
index 6d62b20..960d02f 100755
Binary files a/shf and b/shf differ
diff --git a/shf.mlb b/shf.mlb
index 00b6703..7db8eba 100644
--- a/shf.mlb
+++ b/shf.mlb
@@ -15,6 +15,7 @@ fcore/search-list.sml
 fcore/app-type.sml
 fcore/app-with.sml
 
+fcore/build-search-list.sml
 fcore/text-constants.sml
 ann
   "allowVectorExps true"