diff --git a/Makefile b/Makefile
index e55dd0825..cca58a026 100644
--- a/Makefile
+++ b/Makefile
@@ -51,7 +51,7 @@ clean:
 	rm -rf .build
 	rm -rf $(JSDEPS)
 
-build: .build/ui js
+build: .build/ui .build/js
 
 .build/ui: $(shell find designer -name '*.ui')
 	./tools/build_ui.sh
@@ -86,12 +86,9 @@ pytype: .build/pytype
 	pytype --config pytype.conf
 	touch $@
 
-.PHONY: js
+TSDEPS := $(wildcard ts/src/*.ts)
+JSDEPS := $(patsubst ts/src/%.ts, web/%.js, $(TSDEPS))
 
-TSDEPS := $(wildcard ts/*.ts)
-JSDEPS := $(patsubst ts/%.ts, web/%.js, $(TSDEPS))
-
-js: $(JSDEPS)
-
-web/%.js: ts/%.ts
-	(cd ts && ./node_modules/.bin/tsc --lib es6,dom lib/global.d.ts $(notdir $<) --outFile ../web/$(notdir $@))
+.build/js: $(TSDEPS)
+	(cd ts && ./node_modules/.bin/tsc --build)
+	touch $@
diff --git a/ts/.gitignore b/ts/.gitignore
index 3c3629e64..35523de68 100644
--- a/ts/.gitignore
+++ b/ts/.gitignore
@@ -1 +1,2 @@
 node_modules
+.buildinfo
diff --git a/ts/deckbrowser.ts b/ts/src/deckbrowser.ts
similarity index 100%
rename from ts/deckbrowser.ts
rename to ts/src/deckbrowser.ts
diff --git a/ts/editor.ts b/ts/src/editor.ts
similarity index 100%
rename from ts/editor.ts
rename to ts/src/editor.ts
diff --git a/ts/overview.ts b/ts/src/overview.ts
similarity index 100%
rename from ts/overview.ts
rename to ts/src/overview.ts
diff --git a/ts/reviewer-bottom.ts b/ts/src/reviewer-bottom.ts
similarity index 100%
rename from ts/reviewer-bottom.ts
rename to ts/src/reviewer-bottom.ts
diff --git a/ts/reviewer.ts b/ts/src/reviewer.ts
similarity index 100%
rename from ts/reviewer.ts
rename to ts/src/reviewer.ts
diff --git a/ts/lib/global.d.ts b/ts/src/types/global.d.ts
similarity index 100%
rename from ts/lib/global.d.ts
rename to ts/src/types/global.d.ts
diff --git a/ts/webview.ts b/ts/src/webview.ts
similarity index 100%
rename from ts/webview.ts
rename to ts/src/webview.ts
diff --git a/ts/tsconfig.json b/ts/tsconfig.json
new file mode 100644
index 000000000..9a00499e8
--- /dev/null
+++ b/ts/tsconfig.json
@@ -0,0 +1,23 @@
+{
+  "compilerOptions": {
+    "target": "es6",
+    "module": "commonjs",
+    "lib": [
+      "es6",
+      "dom"
+    ],
+    "rootDir": "src",
+    "outDir": "../web",
+    "incremental": true,
+    "tsBuildInfoFile": "./.buildinfo",
+    "strict": true,
+    /* Enable all strict type-checking options. */
+    "noImplicitAny": false,
+    /* Raise error on expressions and declarations with an implied 'any' type. */
+    "strictNullChecks": false,
+    /* Enable strict null checks. */
+    "noImplicitThis": false,
+    /* Raise error on 'this' expressions with an implied 'any' type. */
+    "esModuleInterop": true
+  }
+}