Include symbol names in the wasm output

Cargo.toml

@@ -15,6 +15,15 @@ publish = false
 [package.metadata.docs.rs]
 rustdoc-args = ["--cfg", "docsrs"]
 
+################################################################################
+#
+# Configuration for `wasm-pack`
+#
+# See https://rustwasm.github.io/docs/wasm-pack/cargo-toml-configuration.html
+# for details of what can be set here.
+#
+################################################################################
+
 [package.metadata.wasm-pack.profile.profiling]
 wasm-opt = false
 
@@ -24,7 +33,18 @@ demangle-name-section = true
 dwarf-debug-info = true
 
 [package.metadata.wasm-pack.profile.release]
-wasm-opt = ['-Oz']
+# Tell wasm-opt to:
+#  * `-Oz`: optimise for size
+#  * `-g`: include the "name" section (which holds the printable names for
+#    symbols) in the output.
+wasm-opt = ['-Oz', '-g']
+
+################################################################################
+
+[profile.release]
+# Tell cargo to run `rustc` with `-C debuginfo=2` - ie, to include debug symbols.
+# https://doc.rust-lang.org/cargo/reference/profiles.html#debug
+debug = true
 
 [lib]
 crate-type = ["cdylib"]