diff --git a/.editorconfig b/.editorconfig
index 91677d7..4421c37 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -4,3 +4,5 @@ end_of_line = lf
 insert_final_newline = true
 indent_size = 2
 indent_style = space
+[Makefile]
+indent_style = tab
diff --git a/TODO.md b/TODO.md
index 89a9d9a..b4d5b89 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,6 +1,19 @@
 
 ## TODO
 
+- [ ] Show Either
+- [ ] `local` for `where`-like `let` clauses? (I want a `where` that closes over more stuff)
+- [ ] Erasure checking happens at compile time and isn't surfaced to editor..
+- [ ] Add Foldable?
+- [ ] "Failed to unify %var0 and %var1" - get names in there
+  - Need fancier `Env`
+- [ ] add missing cases should skip indented lines
+- [ ] add missing cases should handle `_::_`
+- [ ] "Not in scope" should offer to import
+- [ ] Dependent records (I guess I missed that bit)
+- [ ] Arguments on records
+- [ ] Add sugar for type aliases (maybe infer arguments)
+- [ ] see if we can get a better error on `for` instead of `for_` in do blocks
 - [ ] Maybe make the editor json more compact
 - [ ] Remove erased args from primitive functions
   - But we need separate `+` functions rather than the magic `∀ a. a -> a -> a` to support other backends
@@ -28,6 +41,7 @@
 - [ ] Look into using holes for errors (https://types.pl/@AndrasKovacs/115401455046442009)
   - This would let us hit more cases in a function when we hit an error.
   - I've been wanting to try holes for parse errors too.
+  - [ ] Missing `∀ k` in type is error -> no declaration for, if we insert a hole, we can get the declaration.
 - [ ] in-scope type at point in vscode
   - So the idea here is that the references will be via FC, we remember the type at declaration and then point the usage back to the declaration (FC -> FC). We could dump all of this. (If we're still doing json.)
   - This information _could_ support renaming, too (but there may be indentation issues).
diff --git a/newt-vscode/src/abbrev.ts b/newt-vscode/src/abbrev.ts
index b380107..c8b3ada 100644
--- a/newt-vscode/src/abbrev.ts
+++ b/newt-vscode/src/abbrev.ts
@@ -29,6 +29,8 @@ export const ABBREV: Record<string, string> = {
   "\\Gs": "σ",
   "\\Gt": "τ",
   "\\GD": "Δ",
+  "\\GS": "Σ",
+  "\\GP": "∏",
   "\\[[": "⟦",
   "\\]]": "⟧",
 };
diff --git a/newt-vscode/syntaxes/newt.tmLanguage.json b/newt-vscode/syntaxes/newt.tmLanguage.json
index 6cb2f8f..e0fbcb2 100644
--- a/newt-vscode/syntaxes/newt.tmLanguage.json
+++ b/newt-vscode/syntaxes/newt.tmLanguage.json
@@ -3,6 +3,10 @@
   "name": "newt",
   "scopeName": "source.newt",
   "patterns": [
+    {
+      "name": "invalid.illegal.trace",
+      "match": "\\b(trace|fatalError)\\b"
+    },
     {
       "name": "comment.block.newt",
       "begin": "/-",
diff --git a/src/Lib/Elab.newt b/src/Lib/Elab.newt
index 64ba985..ca01b55 100644
--- a/src/Lib/Elab.newt
+++ b/src/Lib/Elab.newt
@@ -526,6 +526,7 @@ unify env mode t u = do
     unifyVar : Val -> Val -> M UnifyResult
     unifyVar t'@(VVar fc k sp)  u'@(VVar fc' k' sp')  =
       if k == k' then unifySpine env mode (k == k') sp sp'
+      -- FIXME - get some names in here.
       else error fc "Failed to unify \{show t'} and \{show u'}"
 
     unifyVar t'@(VVar fc k Lin) u = do
diff --git a/src/Lib/Erasure.newt b/src/Lib/Erasure.newt
index bfe21d7..d05c9e2 100644
--- a/src/Lib/Erasure.newt
+++ b/src/Lib/Erasure.newt
@@ -44,8 +44,10 @@ eraseSpine env t ((fc, arg) :: args) _ = do
   eraseSpine env (App fc t u) args Nothing
 
 doAlt : EEnv -> CaseAlt -> M CaseAlt
--- REVIEW do we extend env?
+-- REVIEW we're sticking Erased on RHS for impossible, might want a runtime error or elide the case.
+doAlt env (CaseDefault (Erased fc)) = pure $ CaseDefault (Erased fc)
 doAlt env (CaseDefault t) = CaseDefault <$> erase env t Nil
+doAlt env (CaseCons name args (Erased fc)) = pure (CaseCons name args (Erased fc))
 doAlt env (CaseCons name args t) = do
   top <- getTop
   let (Just (MkEntry _ str type def _)) = lookup name top
diff --git a/src/Lib/Tokenizer.newt b/src/Lib/Tokenizer.newt
index 6989484..e3645e9 100644
--- a/src/Lib/Tokenizer.newt
+++ b/src/Lib/Tokenizer.newt
@@ -56,6 +56,7 @@ quoteTokenise ts@(TS el ec toks chars) startl startc acc = case chars of
   -- TODO newline in string should be an error
   '\n' :: cs => Left $ E (MkFC "" (MkBounds el ec el ec)) "Newline in string"
   '\\' :: 'n' :: cs => quoteTokenise (TS el (ec + 2) toks cs) startl startc (acc :< '\n')
+  '\\' :: 't' :: cs => quoteTokenise (TS el (ec + 2) toks cs) startl startc (acc :< chr 9)
   '\\' :: c :: cs => quoteTokenise (TS el (ec + 2) toks cs) startl startc (acc :< c)
   c :: cs => quoteTokenise (TS el (ec + 1) toks cs) startl startc (acc :< c)
   Nil => Left $ E (MkFC "" (MkBounds el ec el ec)) "Expected '\"' at EOF"
@@ -103,7 +104,10 @@ rawTokenise ts@(TS sl sc toks chars) = case chars of
   '_' :: ',' :: '_' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_,_") cs)
   '_' :: '.' :: '_' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) MixFix "_._") cs)
   '\'' :: '\\' :: c :: '\'' :: cs =>
-    let ch = ite (c == 'n') '\n' c
+    let ch = case c of
+              'n' => '\n'
+              't' => chr 9
+              c => c
     in rawTokenise (TS sl (sc + 4) (toks :< mktok False sl (sc + 4) Character (singleton ch)) cs)
   '\'' :: c :: '\'' :: cs => rawTokenise (TS sl (sc + 3) (toks :< mktok False sl (sc + 3) Character (singleton c)) cs)
   '#' :: cs => doRest (TS sl (sc + 1) toks cs) Pragma isIdent (Lin :< '#')
diff --git a/src/Prelude.newt b/src/Prelude.newt
index 90fa041..d0b8db0 100644
--- a/src/Prelude.newt
+++ b/src/Prelude.newt
@@ -787,7 +787,7 @@ instance Cast Int Nat where
   cast n = intToNat n
 
 instance Show Char where
-  show c = jsShow c
+  show c = "'\{jsShow c}'"
 
 swap : ∀ a b. a × b → b × a
 swap (a,b) = (b,a)
@@ -885,7 +885,7 @@ ignore = map (const MkUnit)
 
 instance ∀ a. {{Show a}} → Show (Maybe a) where
   show Nothing = "Nothing"
-  show (Just a) = "Just {show a}"
+  show (Just a) = "Just \{show a}"
 
 pfunc isPrefixOf uses (True False): String → String → Bool := `(pfx, s) => s.startsWith(pfx) ? Prelude_True : Prelude_False`
 pfunc isSuffixOf uses (True False): String → String → Bool := `(pfx, s) => s.endsWith(pfx) ? Prelude_True : Prelude_False`