Update to require ldc 1.13.0-beta2 for -fvisibility=hidden

README.md

@@ -17,14 +17,24 @@ You can add any extra css/js you'll need to the `index.template.html`, or you ca
 
 # How to compile your application
 
-Make sure to have ldc 1.12 installed. Also, make sure that ``ldc2 --version`` returns the `wasm32` among its target types. If not, you may need to install ldc from official sources or run one in docker.
+Make sure to have at least ldc 1.13.0-beta2 installed. Also, make sure that ``ldc2 --version`` returns the `wasm32` among its target types. If not, you may need to install ldc from official sources or run one in docker.
 
 Run `dub build --compiler=ldc2 --build=release` to compile your application, then run `npx webpack` to generate the `index.html`.
 
 You can also `npm run start` to start a webpack development server that serves your application on localhost:3000 (it builds anytime the `app.js` or `index.template.html` changes).
 
 * Note: I could not get it to build on my aged mac (el capitan). Instead I use docker to run ldc in ubuntu.
 
+# Optimizing for size
+
+Since ldc 1.13.0-beta2 there is the `-fvisibility=hidden` flag that hides all functions that aren't explicitly prefixed with the `export` keyword. This flag reduces binary size considerably and has reduced the need for manual stripping almost completely. 
+
+By default symbol names aren't stripped, which means the full mangled name is in the binary, this is convenient for debugging but adds to the binary's size. Add `-strip-all` to the lflags in your `dub.(sdl|json)` to strip all internal function names.
+
+For yet unknown reasons a pointer to each struct's init section gets exported as a global. These globals are completely unused and add some additional bloat. The binaryen project has several tools to (dis)assemble a wasm to text representation and back, which allows manual removing of those exported symbols.
+
+Also, llvm doesn't skip consecutive zeros in the data segment. Running wasm-opt (from binaryen project) removes them and reduces code size further.
+
 # Examples
 
 There is todo-mvc example project in this repo. It implements the famous [todo mvc application](http://todomvc.com).
@@ -71,7 +81,7 @@ Properties can also be a result of a function.
 ```d
 struct App {
   mixin Node!"div";
-  @prop bool innerText() {
+  @prop string innerText() {
     return "Hello World!"
   };
 }

dub.sdl

@@ -3,8 +3,8 @@ description "A framework for writing single page applications"
 authors "Sebastiaan Koppe"
 copyright "Copyright © 2018, Sebastiaan Koppe"
 license "MIT"
-dflags "-mtriple=wasm32-unknown-unknown-wasm" "-Oz" "-betterC"
-lflags "-allow-undefined" "-import-memory" "-strip-all"
+dflags "-mtriple=wasm32-unknown-unknown-wasm" "-betterC" "-fvisibility=hidden"
+lflags "-allow-undefined" "-import-memory"
 dependency "stdx-allocator" version="2.77.3"
 #target "library"
 subPackage "bootstrap-webpack"