polymorph-components · lannbot · Aug 12, 2026 · Aug 12, 2026
diff --git a/AGENTS.md b/AGENTS.md
@@ -31,7 +31,7 @@ Layout (each directory's justfile module in parentheses):
 - `js/deltic/` (`just deltic-module-check`) — `websocket.ts`, THE
   browser-first JS host module, over
   [deltic](https://github.com/lann/deltic)'s embedder conventions (typed
-  streams, `WitError`) for its runtime-linked, no-transpile legs
+  streams, `ComponentException`) for its runtime-linked, no-transpile legs
   (`conformance/driver-ct/deltic/`, the WPT parity round trip, the demo).
   Its knobs are exported functions (`configure`,
   `setMaxInboundBufferBytes`, `setConnectTimeoutMs`, `setCloseTimeoutMs`);
@@ -42,7 +42,7 @@ Layout (each directory's justfile module in parentheses):
   upstream commit) which must agree on the `@deltic/runtime` version
   (deltic's `wasi-shims` imports `@deltic/runtime/embedder` by bare
   specifier internally, so a drift would load the embedder module twice
-  and break `instanceof WitError` across the boundary); the root
+  and break `instanceof ComponentException` across the boundary); the root
   justfile's `exam-deltic` recipe (CI-wired) asserts one version
   repo-wide. Bump procedure: `conformance/driver-ct/deltic/README.md`.
 - `js/componentize/` (`just wpt::…`) — `websocket.js`, the WHATWG-API

diff --git a/README.md b/README.md
@@ -47,7 +47,7 @@ in-guest.
 | Path | Deliverable |
 | --- | --- |
 | [`wit/`](wit) | The `polymorph:websocket` package: a `types` interface for structural types and a `connections` interface owning the `websocket` resource. One copy at the root; consumers pull it in via `wit/deps` symlinks. Package-wide contracts live in [`wit/README.md`](wit/README.md). |
-| [`js/deltic`](js/deltic) | The **browser-first JS host module** (`websocket.ts`): the standard `WebSocket` API only, no `node:` modules, no runtime dependencies, over [deltic](https://github.com/lann/deltic)'s embedder conventions (typed streams, `WitError`). Shared verbatim by the demo runner, the conformance JS-host rows, and the WPT parity round trip. |
+| [`js/deltic`](js/deltic) | The **browser-first JS host module** (`websocket.ts`): the standard `WebSocket` API only, no `node:` modules, no runtime dependencies, over [deltic](https://github.com/lann/deltic)'s embedder conventions (typed streams, `ComponentException`). Shared verbatim by the demo runner, the conformance JS-host rows, and the WPT parity round trip. |
 | [`rust/wasmtime`](rust/wasmtime) | The **Wasmtime host crate** (`wasmtime-websocket`): `add_to_linker` + `WasiWebsocketView`, per-store `WasiWebsocketCtx` knobs for the bounds the WIT leaves implementation-defined. |
 | [`js/componentize`](js/componentize) | The **browser-API shim** for componentize-js guests: the WHATWG `WebSocket` interface implemented over the WIT imports — the inverse of `js/deltic` — plus the **WPT parity gate**: vendored web-platform-tests run round-trip (shim → WIT → deltic → platform WebSocket) and held to the platform baseline's pass set. |
 | [`rust/guest-provider`](rust/guest-provider) | The **in-guest provider** (`websocket-guest-provider`): a WebSocket client stack over `wasi:sockets` TCP, exporting the package surface as a composable component; `wss:` via the composed [`polymorph:tls`](https://github.com/polymorph-components/polymorph-tls) component. See its README for the TLS posture and configuration channel. |

diff --git a/conformance/driver-ct/deltic/README.md b/conformance/driver-ct/deltic/README.md
@@ -36,7 +36,7 @@ prereleases"). It is pinned in **two** places, both required to agree:
   SAME `@deltic/runtime` version (the module-identity constraint: deltic's
   `wasi-shims` imports `@deltic/runtime/embedder` by bare specifier
   internally, so every config resolving it must agree, or the embedder
-  module loads twice and `instanceof WitError` stops holding across the
+  module loads twice and `instanceof ComponentException` stops holding across the
   boundary).
 
 `@deltic/translator` ships the translator wasm asset **for the same

diff --git a/conformance/driver-ct/deltic/browser-bundle-entry.ts b/conformance/driver-ct/deltic/browser-bundle-entry.ts
@@ -9,7 +9,7 @@
 // map — the single deltic pin site), the emitted module is what
 // browser/worker-entry.ts imports as `@deltic/release-bundle-entry`
 // used to. Same export surface: instantiate/Translator/runSuite/
-// wasiShims/WitError/artifactsFromEnvelope and friends (49 exports
+// wasiShims/ComponentException/artifactsFromEnvelope and friends (49 exports
 // verified against the retired upstream entry).
 export * from "@deltic/runtime/embedder";
 export { Translator } from "@deltic/runtime/shim";

diff --git a/conformance/driver-ct/deltic/browser/worker-entry.ts b/conformance/driver-ct/deltic/browser/worker-entry.ts
@@ -3,7 +3,7 @@
 // JSR packages' public surface), the upstream worker message loop, and
 // this repo's deltic host module, resolved through ONE import map so the
 // emitted bundle carries exactly one embedder module instance — which is
-// what keeps `instanceof WitError` true when the host module throws
+// what keeps `instanceof ComponentException` true when the host module throws
 // across the component boundary (workers resolve no import maps, so
 // bundling is the only sound shape; see @polymorph/component-test-js's
 // runner-deltic README).

diff --git a/conformance/driver-ct/deltic/deno.json b/conformance/driver-ct/deltic/deno.json
@@ -1,11 +1,11 @@
 {
-  "//": "MODULE-IDENTITY CONSTRAINT: deltic's wasi-shims module imports @deltic/runtime/embedder by bare specifier internally. The @deltic/runtime/embedder entry here must map to the IDENTICAL exact-pinned JSR version as ../../../js/deltic/deno.json's entry, or the embedder module loads twice and `instanceof WitError` stops holding across the module boundary. Pin story: 0.1.0-pre.g50778a1 names one upstream deltic commit; @deltic/translator ships the translator wasm for that SAME commit; deno.lock carries integrity, --frozen enforced everywhere; one version repo-wide is asserted by the pin gate (justfile: exam-deltic).",
+  "//": "MODULE-IDENTITY CONSTRAINT: deltic's wasi-shims module imports @deltic/runtime/embedder by bare specifier internally. The @deltic/runtime/embedder entry here must map to the IDENTICAL exact-pinned JSR version as ../../../js/deltic/deno.json's entry, or the embedder module loads twice and `instanceof ComponentException` stops holding across the module boundary. Pin story: 0.1.0-pre.g078aa15 names one upstream deltic commit; @deltic/translator ships the translator wasm for that SAME commit; deno.lock carries integrity, --frozen enforced everywhere; one version repo-wide is asserted by the pin gate (justfile: exam-deltic).",
   "imports": {
-    "@deltic/ct-runner": "jsr:@deltic/ct-runner@0.1.0-pre.g50778a1",
-    "@deltic/runtime/embedder": "jsr:@deltic/runtime@0.1.0-pre.g50778a1/embedder",
-    "@deltic/runtime/shim": "jsr:@deltic/runtime@0.1.0-pre.g50778a1/shim",
-    "@deltic/wasi-shims": "jsr:@deltic/wasi-shims@0.1.0-pre.g50778a1",
-    "@deltic/translator": "jsr:@deltic/translator@0.1.0-pre.g50778a1",
+    "@deltic/ct-runner": "jsr:@deltic/ct-runner@0.1.0-pre.g078aa15",
+    "@deltic/runtime/embedder": "jsr:@deltic/runtime@0.1.0-pre.g078aa15/embedder",
+    "@deltic/runtime/shim": "jsr:@deltic/runtime@0.1.0-pre.g078aa15/shim",
+    "@deltic/wasi-shims": "jsr:@deltic/wasi-shims@0.1.0-pre.g078aa15",
+    "@deltic/translator": "jsr:@deltic/translator@0.1.0-pre.g078aa15",
     "@polymorph/component-test-js/deltic-worker-main": "./node_modules/@polymorph/component-test-js/js/runner-deltic/worker-main.mjs"
   },
   "minimumDependencyAge": { "age": "P1D", "exclude": ["jsr:@deltic/*"] },

diff --git a/conformance/driver-ct/deltic/deno.lock b/conformance/driver-ct/deltic/deno.lock
diff --git a/conformance/driver-ct/deltic/run.ts b/conformance/driver-ct/deltic/run.ts
@@ -31,7 +31,7 @@
 // `@deltic/runtime/embedder` by bare specifier internally; this leg's
 // `deno.json` AND `js/deltic/deno.json` must map that specifier to the
 // IDENTICAL exact-pinned JSR version, or the embedder module loads twice
-// and `instanceof WitError` stops holding across the module boundary.
+// and `instanceof ComponentException` stops holding across the module boundary.
 //
 // The translator comes from the packaged `@deltic/translator` JSR
 // prerelease (defaultTranslator()) by default — no fetch step, no

diff --git a/examples/deltic-demo/run.ts b/examples/deltic-demo/run.ts
@@ -17,12 +17,12 @@
 // packaged `@deltic/translator` JSR prerelease by default (no fetch
 // step); `--translator <path>` remains as an optional override for a
 // locally-built translator shim. The same import map is what keeps
-// `instanceof WitError` holding across the host-module boundary (see
+// `instanceof ComponentException` holding across the host-module boundary (see
 // that deno.json's MODULE-IDENTITY note).
 
 import { Translator } from "@deltic/runtime/shim";
 import type { ComponentArtifacts } from "@deltic/runtime/embedder";
-import { instantiate, WitError } from "@deltic/runtime/embedder";
+import { ComponentException, instantiate } from "@deltic/runtime/embedder";
 import { defaultTranslator } from "@deltic/translator";
 import { wasiShims } from "@deltic/wasi-shims";
 import { websocketImports } from "../../js/deltic/websocket.ts";
@@ -121,12 +121,12 @@ async function main() {
     };
     // The export's `result<u32, string>` lifts to return-or-throw in
     // return position (contracts/embedder-api.md §"Value mapping"): the
-    // err payload rides a branded `WitError`.
+    // err payload rides a branded `ComponentException`.
     try {
       const received = await demo.run(`${echod.base}/echo`, cli.count);
       console.log(`round-tripped ${received}/${cli.count} messages`);
     } catch (err) {
-      const detail = err instanceof WitError ? err.payload : err;
+      const detail = err instanceof ComponentException ? err.payload : err;
       console.error(`demo failed: ${detail}`);
       Deno.exitCode = 1;
     }

diff --git a/js/componentize/wpt/parity/deltic-carrier.ts b/js/componentize/wpt/parity/deltic-carrier.ts
@@ -25,7 +25,7 @@
 // JSR package's lock-pinned module cache (no fetch step). Bundling from
 // there is also what keeps `@deltic/runtime/embedder` a single module
 // instance across this bundle and js/deltic/websocket.ts, so
-// `instanceof WitError` holds.
+// `instanceof ComponentException` holds.
 
 import { Translator } from "@deltic/runtime/shim";
 import { instantiate } from "@deltic/runtime/embedder";

diff --git a/js/deltic/README.md b/js/deltic/README.md
@@ -7,7 +7,7 @@ Chromium). It began as the [deltic](https://github.com/lann/deltic)-native
 port of the browser-first reference host `js/jco/websocket.js` (retired
 with the jco legs at commit c9252be; see git history), rewritten over
 deltic's embedder API (typed `Stream<T>` / `ReadableStream` rather than
-bare-payload `Stream`, and `WitError` throws rather than
+bare-payload `Stream`, and `ComponentException` throws rather than
 `throw { tag, val }`). It was developed as deltic's own
 `ports/websocket` reference-host port and is upstreamed here per
 [lann/deltic#14](https://github.com/lann/deltic/issues/14); the WIT
@@ -36,7 +36,7 @@ identically on Deno.
 pinned URL as `conformance/driver-ct/deltic/deno.json`. deltic's
 `wasi-shims` module imports that specifier by bare name internally; if the
 two configs ever disagreed, the embedder module would load twice and
-`instanceof WitError` would stop holding across the boundary. Keep both
+`instanceof ComponentException` would stop holding across the boundary. Keep both
 import maps byte-identical for that one entry.
 
 ## Unit tests

diff --git a/js/deltic/deno.json b/js/deltic/deno.json
@@ -2,9 +2,9 @@
   "name": "@polymorph/websocket-deltic",
   "version": "0.0.0",
   "exports": "./websocket.ts",
-  "//": "MODULE-IDENTITY CONSTRAINT: deltic's wasi-shims module imports @deltic/runtime/embedder by bare specifier internally. Every config in this repo (this file AND conformance/driver-ct/deltic/deno.json) must map @deltic/runtime to the IDENTICAL exact-pinned JSR version, or the embedder module loads twice and `instanceof WitError` stops holding across the module boundary. Pin story: 0.1.0-pre.g50778a1 names one upstream deltic commit; @deltic/translator ships the translator wasm for that SAME commit; deno.lock carries integrity, --frozen enforced everywhere; one version repo-wide is asserted by the pin gate (justfile: exam-deltic).",
+  "//": "MODULE-IDENTITY CONSTRAINT: deltic's wasi-shims module imports @deltic/runtime/embedder by bare specifier internally. Every config in this repo (this file AND conformance/driver-ct/deltic/deno.json) must map @deltic/runtime to the IDENTICAL exact-pinned JSR version, or the embedder module loads twice and `instanceof ComponentException` stops holding across the module boundary. Pin story: 0.1.0-pre.g078aa15 names one upstream deltic commit; @deltic/translator ships the translator wasm for that SAME commit; deno.lock carries integrity, --frozen enforced everywhere; one version repo-wide is asserted by the pin gate (justfile: exam-deltic).",
   "imports": {
-    "@deltic/runtime/embedder": "jsr:@deltic/runtime@0.1.0-pre.g50778a1/embedder"
+    "@deltic/runtime/embedder": "jsr:@deltic/runtime@0.1.0-pre.g078aa15/embedder"
   },
   "minimumDependencyAge": { "age": "P1D", "exclude": ["jsr:@deltic/*"] },
   "compilerOptions": {

diff --git a/js/deltic/deno.lock b/js/deltic/deno.lock