Some part way through the adding a language checklist.

.gitmodules

@@ -647,3 +647,6 @@
 [submodule "vendor/grammars/atom-fsharp"]
 	path = vendor/grammars/atom-fsharp
 	url = https://github.com/fsprojects/atom-fsharp
+[submodule "vendor/grammars/SMT.tmbundle"]
+	path = vendor/grammars/SMT.tmbundle
+	url = https://github.com/SRI-CSL/SMT.tmbundle.git

grammars.yml

@@ -85,6 +85,8 @@ vendor/grammars/Racket:
 - source.racket
 vendor/grammars/SCSS.tmbundle:
 - source.scss
+vendor/grammars/SMT.tmbundle:
+- source.smt
 vendor/grammars/Scalate.tmbundle:
 - source.scaml
 - text.html.ssp

lib/linguist/languages.yml

@@ -3135,6 +3135,24 @@ Smarty:
   ace_mode: smarty
   tm_scope: text.html.smarty
 
+SMT:
+  type: programming
+  extensions:
+  - .smt2
+  - .smt
+  interpreters:
+  - boolector
+  - cvc4
+  - mathsat5
+  - opensmt
+  - smtinterpol
+  - smt-rat
+  - stp
+  - verit
+  - yices2
+  - z3
+  tm_scope: source.smt
+
 SourcePawn:
   type: programming
   color: "#5c7611"