Native build optimization

Ordinary Native compilation uses O3, shrink level 2, without convergence. Its recorded recipe is native-bounded-size. No optimization flag is needed:

pulse build
pulse compile

pulse build produces the selected provider's deployment output. pulse compile produces provider-neutral Native Wasm. These settings apply to portable compilation, Node Native and Fastly Native builds. They do not change source eligibility, provider selection or the application's supported behavior.

Choose a recipe

Selection	Recorded recipe	AssemblyScript settings	When to use it
No override	native-bounded-size	O3 / shrink2 / no convergence	The ordinary default, unless the selected Native profile configures another recipe.
--native-shrink0	native-shrink0	O3 / shrink0 / no convergence	Restore the previous recipe when investigating an optimization regression or comparing a workload.
--experimental-native-size	experimental-native-size	O3 / shrink2 / convergence	Try additional optimizer convergence and measure the resulting artifact and compilation cost.
--experimental-native-bounded-size	experimental-native-bounded-size	O3 / shrink2 / no convergence	Keep existing explicit selections and their historical identity; its settings match the ordinary default.

For a one-command override:

pulse build --native-shrink0
pulse compile --native-shrink0
pulse build --experimental-native-size

The three recipe flags are mutually exclusive. An explicit flag overrides nativeOptimization in the selected profile. Without a flag, that profile's setting wins; without either, Pulse uses native-bounded-size.

To keep a selection in .pulse/config.ts, set it on a Native profile:

import { defineConfig } from '@pulse-compute/pulse'

export default defineConfig(() => ({
  pulse: { entry: 'src/index.ts', defaultProfile: 'local' },
  local: {
    host: 'node',
    target: 'native',
    nativeOptimization: 'native-shrink0',
  },
}))

Set nativeOptimization to native-bounded-size, or remove it, to return that profile to the ordinary default. The field accepts all four recipe identities in the table. See project configuration.

JavaScript profiles reject nativeOptimization, and JavaScript pulse build rejects these flags. pulse compile always requests Native compilation, even when the selected profile otherwise targets JavaScript, and still requires Native-compatible source.

Convergence asks the optimizer to continue seeking a stable result; it can add compilation work without reducing the final artifact. Smaller Wasm does not by itself prove lower request latency or memory use. Compare completed builds and representative workloads before adopting an override. Guest-linked builds also have their own prebuilt inputs and final-link optimization; a primary compiler recipe does not replace those steps.

Optional json-as cache arena setting

--elide-json-cache-arena is an independent Native option. It omits json-as's 1 MiB string-cache arena only when string caching is disabled. The default keeps that allocation. Enabled caches retain their arena, and schema-free artifacts are unchanged. It can be combined with one recipe flag:

pulse build --elide-json-cache-arena
pulse compile --native-shrink0 --elide-json-cache-arena

The option reaches portable, Node Native and Fastly Native compilation. JavaScript builds reject it. This is a targeted json-as allocation setting, not a general AssemblyScript optimizer or garbage-collection switch. It does not change schema semantics or reclaim retained values.

Peak memory can increase for allocation-heavy workloads, even though the eager arena allocation is removed. A retained escaped-string stress observation increased linear-memory capacity from 110 MiB to 148 MiB with this option; that observation is not a prediction for another application. Measure startup and peak memory for the workload you intend to run. The adapter is pinned to json-as 1.5.0 and fails if the expected dependency source changes.

Inspect the result

Build manifests and retained reports record the selected recipe. Use a completed build's pulse report or pulse report --html to inspect the actual artifacts; keep the source, target, toolchain and recipe identified when comparing results. Historical absent recipe metadata and default report identities keep their original meaning; they are not reinterpreted as today's bounded default.

The arena selection is recorded as elideJsonCacheArena in the report recipe and jsonAs.elideDisabledCacheArena in schema-active Native manifests. Applied build observations identify schema-cache-arena-transform.cjs. Historical reports without the field did not record the setting.

See the generated CLI reference for exact command syntax and the JSON schema guide for schema admission and limits.