diff --git a/src/Idris/ModTree.idr b/src/Idris/ModTree.idr
index 1c9f89184..a9f2d2b94 100644
--- a/src/Idris/ModTree.idr
+++ b/src/Idris/ModTree.idr
@@ -63,9 +63,10 @@ mkModTree : {auto c : Ref Ctxt Defs} ->
             {auto a : Ref AllMods (List (ModuleIdent, ModTree))} ->
             FC ->
             (done : List ModuleIdent) -> -- if 'mod' is here we have a cycle
-            (mod : ModuleIdent) ->
+            (modFP : Maybe FileName) -> -- Sometimes we know already know what the file name is
+            (mod : ModuleIdent) ->      -- Otherwise we'll compute it from the module name
             Core ModTree
-mkModTree loc done mod
+mkModTree loc done modFP mod
   = if mod `elem` done
        then throw (CyclicImports (done ++ [mod]))
        else
@@ -75,10 +76,10 @@ mkModTree loc done mod
                     -- If we've seen it before, reuse what we found
                     case lookup mod all of
                          Nothing =>
-                           do file <- nsToSource loc mod
+                           do file <- maybe (nsToSource loc mod) pure modFP
                               modInfo <- readHeader file
                               let imps = map path (imports modInfo)
-                              ms <- traverse (mkModTree loc (mod :: done)) imps
+                              ms <- traverse (mkModTree loc (mod :: done) Nothing) imps
                               let mt = MkModTree mod (Just file) ms
                               all <- get AllMods
                               put AllMods ((mod, mt) :: all)
@@ -131,7 +132,7 @@ getBuildMods loc done fname
          if fname_ns `elem` map buildNS done
             then pure []
             else
-              do t <- mkModTree {a} loc [] fname_ns
+              do t <- mkModTree {a} loc [] (Just fname) fname_ns
                  dm <- newRef DoneMod empty
                  o <- newRef BuildOrder []
                  mkBuildMods {d=dm} {o} t
diff --git a/tests/Main.idr b/tests/Main.idr
index 45bfcbf49..92c8a4e7a 100644
--- a/tests/Main.idr
+++ b/tests/Main.idr
@@ -32,7 +32,7 @@ ttimpTests
 
 idrisTests : List String
 idrisTests
-    = -- Fundamental language feturea
+    = -- Fundamental language features
       ["basic001", "basic002", "basic003", "basic004", "basic005",
        "basic006", "basic007", "basic008", "basic009", "basic010",
        "basic011", "basic012", "basic013", "basic014", "basic015",
@@ -71,6 +71,7 @@ idrisTests
        "interface017",
        -- Miscellaneous REPL
        "interpreter001", "interpreter002", "interpreter003", "interpreter004",
+       "interpreter005",
        -- Implicit laziness, lazy evaluation
        "lazy001",
        -- QTT and linearity related
diff --git a/tests/idris2/interpreter005/Issue37.idr b/tests/idris2/interpreter005/Issue37.idr
new file mode 100644
index 000000000..30e9189ec
--- /dev/null
+++ b/tests/idris2/interpreter005/Issue37.idr
@@ -0,0 +1,2 @@
+test : String
+test = "IDR"
diff --git a/tests/idris2/interpreter005/Issue37.lidr b/tests/idris2/interpreter005/Issue37.lidr
new file mode 100644
index 000000000..a3526a9ce
--- /dev/null
+++ b/tests/idris2/interpreter005/Issue37.lidr
@@ -0,0 +1,2 @@
+> test : String
+> test = "LIDR"
diff --git a/tests/idris2/interpreter005/expected b/tests/idris2/interpreter005/expected
new file mode 100644
index 000000000..df04f6a71
--- /dev/null
+++ b/tests/idris2/interpreter005/expected
@@ -0,0 +1,3 @@
+1/1: Building Issue37 (Issue37.lidr)
+Main> "LIDR"
+Main> Bye for now!
diff --git a/tests/idris2/interpreter005/input b/tests/idris2/interpreter005/input
new file mode 100644
index 000000000..131b8c414
--- /dev/null
+++ b/tests/idris2/interpreter005/input
@@ -0,0 +1,2 @@
+test
+:q
diff --git a/tests/idris2/interpreter005/run b/tests/idris2/interpreter005/run
new file mode 100755
index 000000000..c8ffb8d83
--- /dev/null
+++ b/tests/idris2/interpreter005/run
@@ -0,0 +1,3 @@
+$1 --no-banner --no-color --console-width 0 Issue37.lidr < input
+
+rm -rf build