diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f3e6f6051a..4b6c2b7a9c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ env:
 jobs:
   build-fmt-clippy-test:
     name: fmt, clippy, test --release
-    runs-on: [self-hosted]
+    runs-on: [self-hosted, i5-4690K]
     timeout-minutes: 90
     env:
       FORCE_COLOR: 1
diff --git a/Cargo.lock b/Cargo.lock
index 2b247f5517..272d75e8ea 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1949,9 +1949,9 @@ dependencies = [
 
 [[package]]
 name = "js-sys"
-version = "0.3.53"
+version = "0.3.54"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e4bf49d50e2961077d9c99f4b7997d770a1114f087c3c2e0069b36c13fc2979d"
+checksum = "1866b355d9c878e5e607473cbe3f63282c0b7aad2db1dbebf55076c686918254"
 dependencies = [
  "wasm-bindgen",
 ]
@@ -4120,9 +4120,9 @@ dependencies = [
 
 [[package]]
 name = "sha2"
-version = "0.9.6"
+version = "0.9.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9204c41a1597a8c5af23c82d1c921cb01ec0a4c59e07a9c7306062829a3903f3"
+checksum = "91e36fa7752016a6c4483706d634fd82c48860dd2df17a0cfaaebc714f23b2dd"
 dependencies = [
  "block-buffer 0.9.0",
  "cfg-if 1.0.0",
@@ -4785,9 +4785,9 @@ checksum = "fd6fbd9a79829dd1ad0cc20627bf1ed606756a7f77edff7b66b7064f9cb327c6"
 
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.76"
+version = "0.2.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8ce9b1b516211d33767048e5d47fa2a381ed8b76fc48d2ce4aa39877f9f183e0"
+checksum = "5e68338db6becec24d3c7977b5bf8a48be992c934b5d07177e3931f5dc9b076c"
 dependencies = [
  "cfg-if 1.0.0",
  "wasm-bindgen-macro",
@@ -4795,9 +4795,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.76"
+version = "0.2.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cfe8dc78e2326ba5f845f4b5bf548401604fa20b1dd1d365fb73b6c1d6364041"
+checksum = "f34c405b4f0658583dba0c1c7c9b694f3cac32655db463b56c254a1c75269523"
 dependencies = [
  "bumpalo",
  "lazy_static",
@@ -4810,9 +4810,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.26"
+version = "0.4.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "95fded345a6559c2cfee778d562300c581f7d4ff3edb9b0d230d69800d213972"
+checksum = "a87d738d4abc4cf22f6eb142f5b9a81301331ee3c767f2fef2fda4e325492060"
 dependencies = [
  "cfg-if 1.0.0",
  "js-sys",
@@ -4822,9 +4822,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.76"
+version = "0.2.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "44468aa53335841d9d6b6c023eaab07c0cd4bddbcfdee3e2bb1e8d2cb8069fef"
+checksum = "b9d5a6580be83b19dc570a8f9c324251687ab2184e57086f71625feb57ec77c8"
 dependencies = [
  "quote 1.0.9",
  "wasm-bindgen-macro-support",
@@ -4832,9 +4832,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.76"
+version = "0.2.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0195807922713af1e67dc66132c7328206ed9766af3858164fb583eedc25fbad"
+checksum = "e3775a030dc6f5a0afd8a84981a21cc92a781eb429acef9ecce476d0c9113e92"
 dependencies = [
  "proc-macro2 1.0.29",
  "quote 1.0.9",
@@ -4845,9 +4845,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.76"
+version = "0.2.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "acdb075a845574a1fa5f09fd77e43f7747599301ea3417a9fbffdeedfc1f4a29"
+checksum = "c279e376c7a8e8752a8f1eaa35b7b0bee6bb9fb0cdacfa97cc3f1f289c87e2b4"
 
 [[package]]
 name = "wasmer"
diff --git a/cli/tests/cli_run.rs b/cli/tests/cli_run.rs
index 2b075bb660..a5d491d912 100644
--- a/cli/tests/cli_run.rs
+++ b/cli/tests/cli_run.rs
@@ -327,7 +327,7 @@ mod cli_run {
 
                     // TODO fix QuicksortApp and then remove this!
                     match benchmark.filename {
-                        "QuicksortApp.roc" | "TestBase64.roc" => {
+                        "QuicksortApp.roc"  => {
                             eprintln!("WARNING: skipping testing benchmark {} because the test is broken right now!", benchmark.filename);
                             return;
                         }
@@ -608,6 +608,14 @@ fn run_with_wasmer(wasm_path: &std::path::Path, stdin: &[&str]) -> String {
     use std::io::Write;
     use wasmer::{Instance, Module, Store};
 
+    //    std::process::Command::new("cp")
+    //        .args(&[
+    //            wasm_path.to_str().unwrap(),
+    //            "/home/folkertdev/roc/wasm/nqueens.wasm",
+    //        ])
+    //        .output()
+    //        .unwrap();
+
     let store = Store::default();
     let module = Module::from_file(&store, &wasm_path).unwrap();
 
diff --git a/compiler/build/src/link.rs b/compiler/build/src/link.rs
index a2c1fc40de..0be0ac00d6 100644
--- a/compiler/build/src/link.rs
+++ b/compiler/build/src/link.rs
@@ -606,26 +606,27 @@ fn link_wasm32(
 ) -> io::Result<(Child, PathBuf)> {
     let zig_str_path = find_zig_str_path();
 
-    let child =
-        Command::new("/home/folkertdev/Downloads/zig-linux-x86_64-0.9.0-dev.848+d5ef5da59/zig")
-            // .env_clear()
-            // .env("PATH", &env_path)
-            .args(&["build-exe"])
-            .args(input_paths)
-            .args([
-                &format!("-femit-bin={}", output_path.to_str().unwrap()),
-                // include libc
-                "-lc",
-                "-target",
-                "wasm32-wasi",
-                "--pkg-begin",
-                "str",
-                zig_str_path.to_str().unwrap(),
-                "--pkg-end",
-                // useful for debugging
-                // "-femit-llvm-ir=/home/folkertdev/roc/roc/examples/benchmarks/platform/host.ll",
-            ])
-            .spawn()?;
+    let child = Command::new("zig9")
+        // .env_clear()
+        // .env("PATH", &env_path)
+        .args(&["build-exe"])
+        .args(input_paths)
+        .args([
+            &format!("-femit-bin={}", output_path.to_str().unwrap()),
+            // include libc
+            "-lc",
+            "-target",
+            "wasm32-wasi-musl",
+            "--pkg-begin",
+            "str",
+            zig_str_path.to_str().unwrap(),
+            "--pkg-end",
+            "--strip",
+            // "-O", "ReleaseSmall",
+            // useful for debugging
+            // "-femit-llvm-ir=/home/folkertdev/roc/roc/examples/benchmarks/platform/host.ll",
+        ])
+        .spawn()?;
 
     Ok((child, output_path))
 }
diff --git a/compiler/builtins/bitcode/src/str.zig b/compiler/builtins/bitcode/src/str.zig
index 2172e693d7..801550663c 100644
--- a/compiler/builtins/bitcode/src/str.zig
+++ b/compiler/builtins/bitcode/src/str.zig
@@ -1150,8 +1150,8 @@ fn strToBytes(arg: RocStr) RocList {
 }
 
 const FromUtf8Result = extern struct {
-    byte_index: usize,
     string: RocStr,
+    byte_index: usize,
     is_ok: bool,
     problem_code: Utf8ByteProblem,
 };
diff --git a/compiler/gen_llvm/src/llvm/build.rs b/compiler/gen_llvm/src/llvm/build.rs
index ebf0ecbc29..b8c9b922e8 100644
--- a/compiler/gen_llvm/src/llvm/build.rs
+++ b/compiler/gen_llvm/src/llvm/build.rs
@@ -2189,8 +2189,15 @@ fn list_literal<'a, 'ctx, 'env>(
         let global = {
             let mut global_elements = Vec::with_capacity_in(list_length, env.arena);
 
-            // insert NULL bytes for the refcount
-            // these elements are (dropped again if the list contains non-constants)
+            // Add zero bytes that represent the refcount
+            //
+            // - if all elements are const, then we store the whole list as a constant.
+            //      It then needs a refcount before the first element.
+            // - but if the list is not all constants, then we will just copy the constant values,
+            //      and we do not need that refcount at the start
+            //
+            // In the latter case, we won't store the zeros in the globals
+            // (we slice them off again below)
             for _ in 0..zero_elements {
                 global_elements.push(element_type.const_zero());
             }
diff --git a/compiler/gen_llvm/src/llvm/build_str.rs b/compiler/gen_llvm/src/llvm/build_str.rs
index 3b35d6d9a9..87a8c50c57 100644
--- a/compiler/gen_llvm/src/llvm/build_str.rs
+++ b/compiler/gen_llvm/src/llvm/build_str.rs
@@ -1,5 +1,5 @@
 use crate::llvm::bitcode::{call_bitcode_fn, call_void_bitcode_fn};
-use crate::llvm::build::{complex_bitcast, Env, Scope};
+use crate::llvm::build::{complex_bitcast, struct_from_fields, Env, Scope};
 use crate::llvm::build_list::{allocate_list, call_bitcode_fn_returns_list, store_list};
 use inkwell::builder::Builder;
 use inkwell::values::{BasicValueEnum, FunctionValue, IntValue, PointerValue, StructValue};
@@ -260,6 +260,73 @@ pub fn str_to_utf8<'a, 'ctx, 'env>(
     call_bitcode_fn_returns_list(env, &[string], bitcode::STR_TO_UTF8)
 }
 
+fn decode_from_utf8_result<'a, 'ctx, 'env>(
+    env: &Env<'a, 'ctx, 'env>,
+    pointer: PointerValue<'ctx>,
+) -> StructValue<'ctx> {
+    let builder = env.builder;
+    let ctx = env.context;
+
+    let fields = match env.ptr_bytes {
+        8 => [
+            env.ptr_int().into(),
+            super::convert::zig_str_type(env).into(),
+            env.context.bool_type().into(),
+            ctx.i8_type().into(),
+        ],
+        4 => [
+            super::convert::zig_str_type(env).into(),
+            env.ptr_int().into(),
+            env.context.bool_type().into(),
+            ctx.i8_type().into(),
+        ],
+        _ => unreachable!(),
+    };
+
+    let record_type = env.context.struct_type(&fields, false);
+
+    match env.ptr_bytes {
+        8 => {
+            let zig_struct = builder
+                .build_load(pointer, "load_utf8_validate_bytes_result")
+                .into_struct_value();
+
+            let string = builder
+                .build_extract_value(zig_struct, 0, "string")
+                .unwrap();
+
+            let byte_index = builder
+                .build_extract_value(zig_struct, 1, "byte_index")
+                .unwrap();
+
+            let is_ok = builder.build_extract_value(zig_struct, 2, "is_ok").unwrap();
+
+            let problem_code = builder
+                .build_extract_value(zig_struct, 3, "problem_code")
+                .unwrap();
+
+            let values = [byte_index, string, is_ok, problem_code];
+
+            struct_from_fields(env, record_type, values.iter().copied().enumerate())
+        }
+        4 => {
+            let result_ptr_cast = env
+                .builder
+                .build_bitcast(
+                    pointer,
+                    record_type.ptr_type(AddressSpace::Generic),
+                    "to_unnamed",
+                )
+                .into_pointer_value();
+
+            builder
+                .build_load(result_ptr_cast, "load_utf8_validate_bytes_result")
+                .into_struct_value()
+        }
+        _ => unreachable!(),
+    }
+}
+
 /// Str.fromUtf8 : List U8, { count : Nat, start : Nat } -> { a : Bool, b : Str, c : Nat, d : I8 }
 pub fn str_from_utf8_range<'a, 'ctx, 'env>(
     env: &Env<'a, 'ctx, 'env>,
@@ -268,7 +335,6 @@ pub fn str_from_utf8_range<'a, 'ctx, 'env>(
     count_and_start: StructValue<'ctx>,
 ) -> BasicValueEnum<'ctx> {
     let builder = env.builder;
-    let ctx = env.context;
 
     let result_type = env.module.get_struct_type("str.FromUtf8Result").unwrap();
     let result_ptr = builder.build_alloca(result_type, "alloca_utf8_validate_bytes_result");
@@ -293,26 +359,7 @@ pub fn str_from_utf8_range<'a, 'ctx, 'env>(
         bitcode::STR_FROM_UTF8_RANGE,
     );
 
-    let record_type = env.context.struct_type(
-        &[
-            env.ptr_int().into(),
-            super::convert::zig_str_type(env).into(),
-            env.context.bool_type().into(),
-            ctx.i8_type().into(),
-        ],
-        false,
-    );
-
-    let result_ptr_cast = env
-        .builder
-        .build_bitcast(
-            result_ptr,
-            record_type.ptr_type(AddressSpace::Generic),
-            "to_unnamed",
-        )
-        .into_pointer_value();
-
-    builder.build_load(result_ptr_cast, "load_utf8_validate_bytes_result")
+    decode_from_utf8_result(env, result_ptr).into()
 }
 
 /// Str.fromUtf8 : List U8 -> { a : Bool, b : Str, c : Nat, d : I8 }
@@ -322,7 +369,6 @@ pub fn str_from_utf8<'a, 'ctx, 'env>(
     original_wrapper: StructValue<'ctx>,
 ) -> BasicValueEnum<'ctx> {
     let builder = env.builder;
-    let ctx = env.context;
 
     let result_type = env.module.get_struct_type("str.FromUtf8Result").unwrap();
     let result_ptr = builder.build_alloca(result_type, "alloca_utf8_validate_bytes_result");
@@ -341,26 +387,7 @@ pub fn str_from_utf8<'a, 'ctx, 'env>(
         bitcode::STR_FROM_UTF8,
     );
 
-    let record_type = env.context.struct_type(
-        &[
-            env.ptr_int().into(),
-            super::convert::zig_str_type(env).into(),
-            env.context.bool_type().into(),
-            ctx.i8_type().into(),
-        ],
-        false,
-    );
-
-    let result_ptr_cast = env
-        .builder
-        .build_bitcast(
-            result_ptr,
-            record_type.ptr_type(AddressSpace::Generic),
-            "to_unnamed",
-        )
-        .into_pointer_value();
-
-    builder.build_load(result_ptr_cast, "load_utf8_validate_bytes_result")
+    decode_from_utf8_result(env, result_ptr).into()
 }
 
 /// Str.fromInt : Int -> Str
diff --git a/compiler/gen_wasm/tests/helpers/eval_simple.rs b/compiler/gen_wasm/tests/helpers/eval.rs
similarity index 93%
rename from compiler/gen_wasm/tests/helpers/eval_simple.rs
rename to compiler/gen_wasm/tests/helpers/eval.rs
index d3e69431f8..e809bbf075 100644
--- a/compiler/gen_wasm/tests/helpers/eval_simple.rs
+++ b/compiler/gen_wasm/tests/helpers/eval.rs
@@ -139,7 +139,7 @@ where
 
     let is_gen_test = true;
     let instance =
-        crate::helpers::eval_simple::helper_wasm(&arena, src, stdlib, is_gen_test, ignore_problems);
+        crate::helpers::eval::helper_wasm(&arena, src, stdlib, is_gen_test, ignore_problems);
 
     let main_function = instance.exports.get_function("#UserApp_main_1").unwrap();
 
@@ -166,8 +166,7 @@ where
 #[macro_export]
 macro_rules! assert_wasm_evals_to {
     ($src:expr, $expected:expr, $ty:ty, $transform:expr, $ignore_problems:expr) => {
-        match $crate::helpers::eval_simple::assert_wasm_evals_to_help::<$ty>($src, $ignore_problems)
-        {
+        match $crate::helpers::eval::assert_wasm_evals_to_help::<$ty>($src, $ignore_problems) {
             Err(msg) => println!("{:?}", msg),
             Ok(actual) => {
                 #[allow(clippy::bool_assert_comparison)]
@@ -177,13 +176,7 @@ macro_rules! assert_wasm_evals_to {
     };
 
     ($src:expr, $expected:expr, $ty:ty) => {
-        $crate::assert_wasm_evals_to!(
-            $src,
-            $expected,
-            $ty,
-            $crate::helpers::eval_simple::identity,
-            false
-        );
+        $crate::assert_wasm_evals_to!($src, $expected, $ty, $crate::helpers::eval::identity, false);
     };
 
     ($src:expr, $expected:expr, $ty:ty, $transform:expr) => {
@@ -194,7 +187,7 @@ macro_rules! assert_wasm_evals_to {
 #[macro_export]
 macro_rules! assert_evals_to {
     ($src:expr, $expected:expr, $ty:ty) => {{
-        assert_evals_to!($src, $expected, $ty, $crate::helpers::eval_simple::identity);
+        assert_evals_to!($src, $expected, $ty, $crate::helpers::eval::identity);
     }};
     ($src:expr, $expected:expr, $ty:ty, $transform:expr) => {
         // Same as above, except with an additional transformation argument.
diff --git a/compiler/gen_wasm/tests/helpers/eval_full.rs b/compiler/gen_wasm/tests/helpers/eval_full.rs
deleted file mode 100644
index 3e44e0d7cd..0000000000
--- a/compiler/gen_wasm/tests/helpers/eval_full.rs
+++ /dev/null
@@ -1,264 +0,0 @@
-use roc_can::builtins::builtin_defs_map;
-use roc_collections::all::{MutMap, MutSet};
-use roc_gen_wasm::from_wasm32_memory::FromWasm32Memory;
-
-fn promote_expr_to_module(src: &str) -> String {
-    let mut buffer = String::from("app \"test\" provides [ main ] to \"./platform\"\n\nmain =\n");
-
-    for line in src.lines() {
-        // indent the body!
-        buffer.push_str("    ");
-        buffer.push_str(line);
-        buffer.push('\n');
-    }
-
-    buffer
-}
-
-#[allow(dead_code)]
-pub fn helper_wasm<'a>(
-    arena: &'a bumpalo::Bump,
-    src: &str,
-    stdlib: &'a roc_builtins::std::StdLib,
-    _is_gen_test: bool,
-    _ignore_problems: bool,
-) -> wasmer::Instance {
-    use std::path::{Path, PathBuf};
-
-    let filename = PathBuf::from("Test.roc");
-    let src_dir = Path::new("fake/test/path");
-
-    let module_src;
-    let temp;
-    if src.starts_with("app") {
-        // this is already a module
-        module_src = src;
-    } else {
-        // this is an expression, promote it to a module
-        temp = promote_expr_to_module(src);
-        module_src = &temp;
-    }
-
-    let exposed_types = MutMap::default();
-    let loaded = roc_load::file::load_and_monomorphize_from_str(
-        arena,
-        filename,
-        module_src,
-        stdlib,
-        src_dir,
-        exposed_types,
-        8,
-        builtin_defs_map,
-    );
-
-    let loaded = loaded.expect("failed to load module");
-
-    use roc_load::file::MonomorphizedModule;
-    let MonomorphizedModule {
-        procedures: top_procedures,
-        interns,
-        exposed_to_host,
-        ..
-    } = loaded;
-
-    let mut procedures = MutMap::default();
-
-    for (key, proc) in top_procedures {
-        procedures.insert(key, proc);
-    }
-
-    // You can comment and uncomment this block out to get more useful information
-    // while you're working on the wasm backend!
-    // {
-    //     println!("=========== Procedures ==========");
-    //     println!("{:?}", procedures);
-    //     println!("=================================\n");
-
-    //     println!("=========== Interns    ==========");
-    //     println!("{:?}", interns);
-    //     println!("=================================\n");
-
-    //     println!("=========== Exposed    ==========");
-    //     println!("{:?}", exposed_to_host);
-    //     println!("=================================\n");
-    // }
-
-    let exposed_to_host = exposed_to_host.keys().copied().collect::<MutSet<_>>();
-
-    let env = gen_wasm::Env {
-        arena,
-        interns,
-        exposed_to_host,
-    };
-
-    let module_bytes = gen_wasm::build_module(&env, procedures).unwrap();
-
-    // for debugging (e.g. with wasm2wat)
-    if true {
-        use std::io::Write;
-        let mut file =
-            std::fs::File::create("/home/brian/Documents/roc/compiler/gen_wasm/debug.wasm")
-                .unwrap();
-        file.write_all(&module_bytes).unwrap();
-    }
-
-    // now, do wasmer stuff
-
-    use wasmer::{Function, Instance, Module, Store};
-
-    let store = Store::default();
-    // let module = Module::from_file(&store, &test_wasm_path).unwrap();
-    let module = Module::from_binary(&store, &module_bytes).unwrap();
-
-    // First, we create the `WasiEnv`
-    use wasmer_wasi::WasiState;
-    let mut wasi_env = WasiState::new("hello")
-        // .args(&["world"])
-        // .env("KEY", "Value")
-        .finalize()
-        .unwrap();
-
-    // Then, we get the import object related to our WASI
-    // and attach it to the Wasm instance.
-    let mut import_object = wasi_env
-        .import_object(&module)
-        .unwrap_or_else(|_| wasmer::imports!());
-
-    {
-        let mut exts = wasmer::Exports::new();
-
-        let main_function = Function::new_native(&store, fake_wasm_main_function);
-        let ext = wasmer::Extern::Function(main_function);
-        exts.insert("main", ext);
-
-        let main_function = Function::new_native(&store, wasm_roc_panic);
-        let ext = wasmer::Extern::Function(main_function);
-        exts.insert("roc_panic", ext);
-
-        import_object.register("env", exts);
-    }
-
-    Instance::new(&module, &import_object).unwrap()
-}
-
-#[allow(dead_code)]
-fn wasm_roc_panic(address: u32, tag_id: u32) {
-    match tag_id {
-        0 => {
-            let mut string = "";
-
-            MEMORY.with(|f| {
-                let memory = f.borrow().unwrap();
-
-                let ptr: wasmer::WasmPtr<u8, wasmer::Array> = wasmer::WasmPtr::new(address);
-                let width = 100;
-                let c_ptr = (ptr.deref(memory, 0, width)).unwrap();
-
-                use libc::c_char;
-                use std::ffi::CStr;
-                let slice = unsafe { CStr::from_ptr(c_ptr as *const _ as *const c_char) };
-                string = slice.to_str().unwrap();
-            });
-
-            panic!("Roc failed with message: {:?}", string)
-        }
-        _ => todo!(),
-    }
-}
-
-use std::cell::RefCell;
-
-thread_local! {
-    pub static MEMORY: RefCell<Option<&'static wasmer::Memory>> = RefCell::new(None);
-}
-
-#[allow(dead_code)]
-fn fake_wasm_main_function(_: u32, _: u32) -> u32 {
-    panic!("wasm entered the main function; this should never happen!")
-}
-
-#[allow(dead_code)]
-pub fn assert_wasm_evals_to_help<T>(src: &str, ignore_problems: bool) -> Result<T, String>
-where
-    T: FromWasm32Memory,
-{
-    let arena = bumpalo::Bump::new();
-
-    // NOTE the stdlib must be in the arena; just taking a reference will segfault
-    let stdlib = arena.alloc(roc_builtins::std::standard_stdlib());
-
-    let is_gen_test = true;
-    let instance =
-        crate::helpers::eval_full::helper_wasm(&arena, src, stdlib, is_gen_test, ignore_problems);
-
-    let memory = instance.exports.get_memory("memory").unwrap();
-
-    crate::helpers::eval_full::MEMORY.with(|f| {
-        *f.borrow_mut() = Some(unsafe { std::mem::transmute(memory) });
-    });
-
-    let test_wrapper = instance.exports.get_function("test_wrapper").unwrap();
-
-    match test_wrapper.call(&[]) {
-        Err(e) => Err(format!("{:?}", e)),
-        Ok(result) => {
-            let address = match result[0] {
-                wasmer::Value::I32(a) => a,
-                _ => panic!(),
-            };
-
-            let output = <T as crate::helpers::eval_full::FromWasm32Memory>::decode(
-                memory,
-                // skip the RocCallResult tag id
-                address as u32 + 8,
-            );
-
-            Ok(output)
-        }
-    }
-}
-
-#[macro_export]
-macro_rules! assert_wasm_evals_to {
-    ($src:expr, $expected:expr, $ty:ty, $transform:expr, $ignore_problems:expr) => {
-        match $crate::helpers::eval_full::assert_wasm_evals_to_help::<$ty>($src, $ignore_problems) {
-            Err(msg) => println!("{:?}", msg),
-            Ok(actual) => {
-                #[allow(clippy::bool_assert_comparison)]
-                assert_eq!($transform(actual), $expected)
-            }
-        }
-    };
-
-    ($src:expr, $expected:expr, $ty:ty) => {
-        $crate::assert_wasm_evals_to!(
-            $src,
-            $expected,
-            $ty,
-            $crate::helpers::eval_full::identity,
-            false
-        );
-    };
-
-    ($src:expr, $expected:expr, $ty:ty, $transform:expr) => {
-        $crate::assert_wasm_evals_to!($src, $expected, $ty, $transform, false);
-    };
-}
-
-#[macro_export]
-macro_rules! assert_evals_to {
-    ($src:expr, $expected:expr, $ty:ty) => {{
-        assert_evals_to!($src, $expected, $ty, $crate::helpers::eval_full::identity);
-    }};
-    ($src:expr, $expected:expr, $ty:ty, $transform:expr) => {
-        // Same as above, except with an additional transformation argument.
-        {
-            $crate::assert_wasm_evals_to!($src, $expected, $ty, $transform, false);
-        }
-    };
-}
-
-#[allow(dead_code)]
-pub fn identity<T>(value: T) -> T {
-    value
-}
diff --git a/compiler/gen_wasm/tests/helpers/mod.rs b/compiler/gen_wasm/tests/helpers/mod.rs
index 4d22ed81a3..7e538193f7 100644
--- a/compiler/gen_wasm/tests/helpers/mod.rs
+++ b/compiler/gen_wasm/tests/helpers/mod.rs
@@ -1,7 +1,7 @@
 extern crate bumpalo;
 
 #[macro_use]
-pub mod eval_simple;
+pub mod eval;
 
 /// Used in the with_larger_debug_stack() function, for tests that otherwise
 /// run out of stack space in debug builds (but don't in --release builds)
diff --git a/compiler/mono/src/layout.rs b/compiler/mono/src/layout.rs
index 21d50f2715..3568ce5045 100644
--- a/compiler/mono/src/layout.rs
+++ b/compiler/mono/src/layout.rs
@@ -1151,10 +1151,15 @@ impl<'a> Builtin<'a> {
             Float64 => align_of::<f64>() as u32,
             Float32 => align_of::<f32>() as u32,
             Float16 => align_of::<i16>() as u32,
-            Str | EmptyStr => pointer_size,
             Dict(_, _) | EmptyDict => pointer_size,
             Set(_) | EmptySet => pointer_size,
-            List(_) | EmptyList => pointer_size,
+            // we often treat these as i128 (64-bit systems)
+            // or i64 (32-bit systems).
+            //
+            // In webassembly, For that to be safe
+            // they must be aligned to allow such access
+            List(_) | EmptyList => pointer_size.max(8),
+            Str | EmptyStr => pointer_size.max(8),
         }
     }
 
@@ -1240,9 +1245,10 @@ impl<'a> Builtin<'a> {
             Builtin::Str => pointer_size,
             Builtin::Dict(k, v) => k
                 .alignment_bytes(pointer_size)
-                .max(v.alignment_bytes(pointer_size)),
-            Builtin::Set(k) => k.alignment_bytes(pointer_size),
-            Builtin::List(e) => e.alignment_bytes(pointer_size),
+                .max(v.alignment_bytes(pointer_size))
+                .max(pointer_size),
+            Builtin::Set(k) => k.alignment_bytes(pointer_size).max(pointer_size),
+            Builtin::List(e) => e.alignment_bytes(pointer_size).max(pointer_size),
             Builtin::EmptyStr | Builtin::EmptyList | Builtin::EmptyDict | Builtin::EmptySet => {
                 unreachable!("not heap-allocated")
             }
diff --git a/compiler/test_gen/src/helpers/eval.rs b/compiler/test_gen/src/helpers/eval.rs
index 10c770a3d7..dc4c377c84 100644
--- a/compiler/test_gen/src/helpers/eval.rs
+++ b/compiler/test_gen/src/helpers/eval.rs
@@ -366,7 +366,7 @@ pub fn helper_wasm<'a>(
 
     use std::process::Command;
 
-    Command::new("/home/folkertdev/Downloads/zig-linux-x86_64-0.9.0-dev.848+d5ef5da59/zig")
+    Command::new("zig9")
         .current_dir(dir_path)
         .args(&[
             "wasm-ld",