diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f40a7bb..34e92da 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -42,6 +42,21 @@ jobs:
       - name: Benchmarks (linear)
         run: go test -bench . -benchmem -run=^$ ./... | tee bench-linear.txt
 
+      - name: Coverage summary (linear)
+        run: |
+          if [ -f coverage.out ]; then
+            go tool cover -func=coverage.out > coverage-summary.md;
+          else
+            echo "coverage.out not found" > coverage-summary.md;
+          fi
+
+      - name: Upload coverage summary (linear)
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-summary
+          path: coverage-summary.md
+          if-no-files-found: error
+
       - name: Upload benchmarks (linear)
         uses: actions/upload-artifact@v4
         with:
@@ -55,6 +70,9 @@ jobs:
       - name: Prepare npm package folder
         run: make npm-pack
 
+      - name: WASM smoke test (Node)
+        run: node npm/poindexter-wasm/smoke.mjs
+
       - name: Create npm tarball
         id: npm_pack
         run: |
@@ -137,6 +155,21 @@ jobs:
           path: coverage-gonum.out
           if-no-files-found: error
 
+      - name: Coverage summary (gonum)
+        run: |
+          if [ -f coverage-gonum.out ]; then
+            go tool cover -func=coverage-gonum.out > coverage-summary-gonum.md;
+          else
+            echo "coverage-gonum.out not found" > coverage-summary-gonum.md;
+          fi
+
+      - name: Upload coverage summary (gonum)
+        uses: actions/upload-artifact@v4
+        with:
+          name: coverage-summary-gonum
+          path: coverage-summary-gonum.md
+          if-no-files-found: error
+
       - name: Upload benchmarks (gonum)
         uses: actions/upload-artifact@v4
         with:
diff --git a/Makefile b/Makefile
index 4c4a066..ad73155 100644
--- a/Makefile
+++ b/Makefile
@@ -117,8 +117,26 @@ fuzz: ## Run Go fuzz tests for $(FUZZTIME)
 	done
 
 .PHONY: bench
-bench: ## Run benchmarks and write $(BENCHOUT)
-	$(GO) test -bench . -benchmem -run=^$$ ./... | tee $(BENCHOUT)
+# Benchmark configuration variables
+BENCHPKG     ?= ./...
+BENCHFILTER  ?= .
+BENCHTAGS    ?=
+BENCHMEMFLAG ?= -benchmem
+
+bench: ## Run benchmarks (configurable: BENCHPKG, BENCHFILTER, BENCHTAGS, BENCHOUT)
+	$(GO) test $(if $(BENCHTAGS),-tags=$(BENCHTAGS),) -bench $(BENCHFILTER) $(BENCHMEMFLAG) -run=^$$ $(BENCHPKG) | tee $(BENCHOUT)
+
+.PHONY: bench-linear
+bench-linear: ## Run linear-backend benchmarks and write bench-linear.txt
+	$(MAKE) bench BENCHTAGS= BENCHOUT=bench-linear.txt
+
+.PHONY: bench-gonum
+bench-gonum: ## Run gonum-backend benchmarks (includes 100k benches) and write bench-gonum.txt
+	$(MAKE) bench BENCHTAGS=gonum BENCHOUT=bench-gonum.txt
+
+.PHONY: bench-list
+bench-list: ## List available benchmark names for BENCHPKG (use with BENCHPKG=./pkg)
+	$(GO) test $(if $(BENCHTAGS),-tags=$(BENCHTAGS),) -run=^$$ -bench ^$$ -list '^Benchmark' $(BENCHPKG)
 
 .PHONY: lint
 lint: ## Run golangci-lint (requires it installed)
diff --git a/README.md b/README.md
index 634752c..396a316 100644
--- a/README.md
+++ b/README.md
@@ -71,7 +71,9 @@ Explore runnable examples in the repository:
 - examples/kdtree_2d_ping_hop
 - examples/kdtree_3d_ping_hop_geo
 - examples/kdtree_4d_ping_hop_geo_score
+- examples/dht_helpers (convenience wrappers for common DHT schemas)
 - examples/wasm-browser (browser demo using the ESM loader)
+- examples/wasm-browser-ts (TypeScript + Vite local demo)
 
 ### KDTree performance and notes
 - Dual backend support: Linear (always available) and an optimized KD backend enabled when building with `-tags=gonum`. Linear is the default; with the `gonum` tag, the optimized backend becomes the default.
@@ -216,4 +218,21 @@ This project is licensed under the European Union Public Licence v1.2 (EUPL-1.2)
 
 ## Contributing
 
-Contributions are welcome! Please feel free to submit a Pull Request.
\ No newline at end of file
+Contributions are welcome! Please feel free to submit a Pull Request.
+
+
+## Coverage
+
+- CI produces coverage summaries as artifacts on every push/PR:
+  - Default job: `coverage-summary.md` (from `coverage.out`)
+  - Gonum-tag job: `coverage-summary-gonum.md` (from `coverage-gonum.out`)
+- Locally, you can generate and inspect coverage with the Makefile:
+
+```bash
+make cover         # runs tests with race + coverage and prints the total
+make coverfunc     # prints per-function coverage
+make cover-kdtree  # filters coverage to kdtree.go
+make coverhtml     # writes coverage.html for visual inspection
+```
+
+Note: CI also uploads raw coverage profiles as artifacts (`coverage.out`, `coverage-gonum.out`).
diff --git a/bench_kdtree_dual_100k_test.go b/bench_kdtree_dual_100k_test.go
new file mode 100644
index 0000000..f366f8f
--- /dev/null
+++ b/bench_kdtree_dual_100k_test.go
@@ -0,0 +1,35 @@
+//go:build gonum
+
+package poindexter
+
+import "testing"
+
+// 100k-size benchmarks run only in the gonum-tag job to keep CI time reasonable.
+
+func BenchmarkNearest_Linear_Uniform_100k_2D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 2, BackendLinear, true, 0)
+}
+func BenchmarkNearest_Gonum_Uniform_100k_2D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 2, BackendGonum, true, 0)
+}
+
+func BenchmarkNearest_Linear_Uniform_100k_4D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 4, BackendLinear, true, 0)
+}
+func BenchmarkNearest_Gonum_Uniform_100k_4D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 4, BackendGonum, true, 0)
+}
+
+func BenchmarkNearest_Linear_Clustered_100k_2D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 2, BackendLinear, false, 3)
+}
+func BenchmarkNearest_Gonum_Clustered_100k_2D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 2, BackendGonum, false, 3)
+}
+
+func BenchmarkNearest_Linear_Clustered_100k_4D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 4, BackendLinear, false, 3)
+}
+func BenchmarkNearest_Gonum_Clustered_100k_4D(b *testing.B) {
+	benchNearestBackend(b, 100_000, 4, BackendGonum, false, 3)
+}
diff --git a/docs/api.md b/docs/api.md
index 2dad6a4..e390892 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -496,6 +496,53 @@ Notes:
 - These helpers mirror `Build2D/3D/4D`, but use your provided `NormStats` instead of recomputing from the items slice.
 
 
+---
+
+## KDTree Normalization Helpers (N‑D)
+
+Poindexter includes helpers to build KD points from arbitrary dimensions.
+
+```go
+func BuildND[T any](
+    items []T,
+    id func(T) string,
+    features []func(T) float64,
+    weights []float64,
+    invert []bool,
+) ([]KDPoint[T], error)
+
+// Like BuildND but never returns an error. It performs no validation beyond
+// basic length checks and propagates NaN/Inf values from feature extractors.
+func BuildNDNoErr[T any](
+    items []T,
+    id func(T) string,
+    features []func(T) float64,
+    weights []float64,
+    invert []bool,
+) []KDPoint[T]
+```
+
+- `features`: extract raw values per axis.
+- `weights`: per-axis weights, same length as `features`.
+- `invert`: if true for an axis, uses `1 - normalized` before weighting (turns “higher is better” into lower cost).
+- Use `ComputeNormStatsND` + `BuildNDWithStats` to reuse normalization between updates.
+
+Example:
+
+```go
+pts := poindexter.BuildNDNoErr(records,
+    func(r Rec) string { return r.ID },
+    []func(Rec) float64{
+        func(r Rec) float64 { return r.PingMS },
+        func(r Rec) float64 { return r.Hops },
+        func(r Rec) float64 { return r.GeoKM },
+        func(r Rec) float64 { return r.Score },
+    },
+    []float64{1.0, 0.7, 0.2, 1.2},
+    []bool{false, false, false, true},
+)
+```
+
 ---
 
 ## KDTree Backend selection
diff --git a/docs/perf.md b/docs/perf.md
index 67ccc19..80b655d 100644
--- a/docs/perf.md
+++ b/docs/perf.md
@@ -4,8 +4,9 @@ This page summarizes how to measure KDTree performance in this repository and ho
 
 ## How benchmarks are organized
 
-- Micro-benchmarks live in `bench_kdtree_test.go` and `bench_kdtree_dual_test.go` and cover:
-  - `Nearest` in 2D and 4D with N = 1k, 10k
+- Micro-benchmarks live in `bench_kdtree_test.go`, `bench_kdtree_dual_test.go`, and `bench_kdtree_dual_100k_test.go` and cover:
+  - `Nearest` in 2D and 4D with N = 1k, 10k (both backends)
+  - `Nearest` in 2D and 4D with N = 100k (gonum-tag job; linear also measured there)
   - `KNearest(k=10)` in 2D/4D with N = 1k, 10k
   - `Radius` (mid radius r≈0.5 after normalization) in 2D/4D with N = 1k, 10k
 - Datasets: Uniform and 3-cluster synthetic generators in normalized [0,1] spaces.
diff --git a/docs/wasm.md b/docs/wasm.md
index f6d5d0e..d3d0256 100644
--- a/docs/wasm.md
+++ b/docs/wasm.md
@@ -150,3 +150,22 @@ Then open:
 - http://127.0.0.1:8000/examples/wasm-browser/
 
 Open the browser console to see outputs from `nearest`, `kNearest`, and `radius` queries.
+
+### TypeScript + Vite demo (local-only)
+
+A minimal TypeScript demo using Vite is also included:
+
+- Path: `examples/wasm-browser-ts/`
+- Prerequisites: run `make wasm-build` at the repo root first.
+- From the example folder:
+
+```bash
+npm install
+npm run dev
+```
+
+Then open the URL printed by Vite (usually http://127.0.0.1:5173/) and check the browser console.
+
+Notes:
+- The dev script copies `dist/poindexter.wasm`, `dist/wasm_exec.js`, and the ESM loader into the example's `public/` folder before serving.
+- This example is intentionally excluded from CI to keep the pipeline lean.
diff --git a/examples/dht_helpers/main.go b/examples/dht_helpers/main.go
new file mode 100644
index 0000000..9b89710
--- /dev/null
+++ b/examples/dht_helpers/main.go
@@ -0,0 +1,69 @@
+package main
+
+import (
+	"fmt"
+	po "github.com/Snider/Poindexter"
+)
+
+// BuildPingHop2D wraps poindexter.Build2D to construct 2D points from (ping_ms, hop_count).
+func BuildPingHop2D[T any](
+	items []T,
+	id func(T) string,
+	ping func(T) float64,
+	hops func(T) float64,
+	weights [2]float64,
+	invert [2]bool,
+) ([]po.KDPoint[T], error) {
+	return po.Build2D(items, id, ping, hops, weights, invert)
+}
+
+// BuildPingHopGeo3D wraps poindexter.Build3D for (ping_ms, hop_count, geo_km).
+func BuildPingHopGeo3D[T any](
+	items []T,
+	id func(T) string,
+	ping func(T) float64,
+	hops func(T) float64,
+	geoKM func(T) float64,
+	weights [3]float64,
+	invert [3]bool,
+) ([]po.KDPoint[T], error) {
+	return po.Build3D(items, id, ping, hops, geoKM, weights, invert)
+}
+
+// BuildPingHopGeoScore4D wraps poindexter.Build4D for (ping_ms, hop_count, geo_km, score).
+// Typical usage sets invert for score=true so higher score => lower cost.
+func BuildPingHopGeoScore4D[T any](
+	items []T,
+	id func(T) string,
+	ping func(T) float64,
+	hops func(T) float64,
+	geoKM func(T) float64,
+	score func(T) float64,
+	weights [4]float64,
+	invert [4]bool,
+) ([]po.KDPoint[T], error) {
+	return po.Build4D(items, id, ping, hops, geoKM, score, weights, invert)
+}
+
+// Demo program that builds a small tree using the 2D helper and performs a query.
+func main() {
+	type Peer struct {
+		ID           string
+		PingMS, Hops float64
+	}
+	peers := []Peer{{"A", 20, 1}, {"B", 50, 2}, {"C", 10, 3}}
+
+	pts, err := BuildPingHop2D(peers,
+		func(p Peer) string { return p.ID },
+		func(p Peer) float64 { return p.PingMS },
+		func(p Peer) float64 { return p.Hops },
+		[2]float64{1.0, 0.7},
+		[2]bool{false, false},
+	)
+	if err != nil {
+		panic(err)
+	}
+	kdt, _ := po.NewKDTree(pts, po.WithMetric(po.EuclideanDistance{}))
+	best, dist, _ := kdt.Nearest([]float64{0, 0})
+	fmt.Println(best.ID, dist)
+}
diff --git a/examples/dht_helpers/main_test.go b/examples/dht_helpers/main_test.go
new file mode 100644
index 0000000..3d2f77b
--- /dev/null
+++ b/examples/dht_helpers/main_test.go
@@ -0,0 +1,8 @@
+package main
+
+import "testing"
+
+func TestMain_Run(t *testing.T) {
+	// Just ensure the example main runs without panic to contribute to coverage
+	main()
+}
diff --git a/examples/wasm-browser-ts/README.md b/examples/wasm-browser-ts/README.md
new file mode 100644
index 0000000..7ddbbca
--- /dev/null
+++ b/examples/wasm-browser-ts/README.md
@@ -0,0 +1,46 @@
+# WASM Browser Example (TypeScript + Vite)
+
+This is a minimal TypeScript example that runs Poindexter’s WebAssembly build in the browser.
+It bundles a tiny page with Vite and demonstrates creating a KDTree and running `Nearest`,
+`KNearest`, and `Radius` queries.
+
+## Prerequisites
+- Go toolchain installed
+- Node.js 18+ (tested with Node 20)
+
+## Quick start
+
+1) Build the WASM artifacts at the repo root:
+
+```bash
+make wasm-build
+```
+
+This creates `dist/poindexter.wasm` and `dist/wasm_exec.js`.
+
+2) From this example directory, install deps and start the dev server (the script copies the required files into `public/` before starting Vite):
+
+```bash
+npm install
+npm run dev
+```
+
+3) Open the URL printed by Vite (usually http://127.0.0.1:5173/). Open the browser console to see outputs.
+
+## What the dev script does
+- Copies `../../dist/poindexter.wasm` and `../../dist/wasm_exec.js` into `public/`
+- Copies `../../npm/poindexter-wasm/loader.js` into `public/`
+- Starts Vite with `public/` as the static root for those assets
+
+The TypeScript code imports the loader from `/loader.js` and initializes with:
+
+```ts
+const px = await init({
+  wasmURL: '/poindexter.wasm',
+  wasmExecURL: '/wasm_exec.js',
+});
+```
+
+## Notes
+- This example is local-only and not built in CI to keep jobs light.
+- You can adapt the same structure inside your own web projects; alternatively, install the published npm package when available and serve `dist/` as static assets.
diff --git a/examples/wasm-browser-ts/index.html b/examples/wasm-browser-ts/index.html
new file mode 100644
index 0000000..826dd0c
--- /dev/null
+++ b/examples/wasm-browser-ts/index.html
@@ -0,0 +1,25 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <title>Poindexter WASM TS Demo</title>
+    <style>
+      body { font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif; margin: 2rem; }
+      pre { background: #f6f8fa; padding: 1rem; overflow-x: auto; }
+      code { font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; }
+    </style>
+  </head>
+  <body>
+    <h1>Poindexter WASM (TypeScript + Vite)</h1>
+    <p>
+      This demo initializes the WebAssembly build and performs KDTree queries. Open your browser console to see results.
+    </p>
+    <p>
+      Before running, build the WASM artifacts at the repo root:
+    </p>
+    <pre><code>make wasm-build</code></pre>
+
+    <script type="module" src="/src/main.ts"></script>
+  </body>
+</html>
diff --git a/examples/wasm-browser-ts/package.json b/examples/wasm-browser-ts/package.json
new file mode 100644
index 0000000..e4f8f6c
--- /dev/null
+++ b/examples/wasm-browser-ts/package.json
@@ -0,0 +1,16 @@
+{
+  "name": "poindexter-wasm-browser-ts",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "scripts": {
+    "predev": "node scripts/copy-assets.mjs",
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview"
+  },
+  "devDependencies": {
+    "typescript": "^5.4.0",
+    "vite": "^5.0.0"
+  }
+}
diff --git a/examples/wasm-browser-ts/scripts/copy-assets.mjs b/examples/wasm-browser-ts/scripts/copy-assets.mjs
new file mode 100644
index 0000000..3c5d033
--- /dev/null
+++ b/examples/wasm-browser-ts/scripts/copy-assets.mjs
@@ -0,0 +1,40 @@
+// Copies WASM artifacts and loader into the public/ folder before Vite dev/build.
+// Run as an npm script (predev) from this example directory.
+import { cp, mkdir } from 'node:fs/promises';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = dirname(__filename);
+
+async function main() {
+  const root = resolve(__dirname, '../../..');
+  const exampleDir = resolve(__dirname, '..');
+  const publicDir = resolve(exampleDir, 'public');
+
+  await mkdir(publicDir, { recursive: true });
+
+  const sources = [
+    // WASM artifacts built by `make wasm-build`
+    resolve(root, 'dist/poindexter.wasm'),
+    resolve(root, 'dist/wasm_exec.js'),
+    // ESM loader shipped with the repo's npm folder
+    resolve(root, 'npm/poindexter-wasm/loader.js'),
+  ];
+
+  const targets = [
+    resolve(publicDir, 'poindexter.wasm'),
+    resolve(publicDir, 'wasm_exec.js'),
+    resolve(publicDir, 'loader.js'),
+  ];
+
+  for (let i = 0; i < sources.length; i++) {
+    await cp(sources[i], targets[i]);
+    console.log(`Copied ${sources[i]} -> ${targets[i]}`);
+  }
+}
+
+main().catch((err) => {
+  console.error('copy-assets failed:', err);
+  process.exit(1);
+});
diff --git a/examples/wasm-browser-ts/src/main.ts b/examples/wasm-browser-ts/src/main.ts
new file mode 100644
index 0000000..574a8bc
--- /dev/null
+++ b/examples/wasm-browser-ts/src/main.ts
@@ -0,0 +1,33 @@
+// Minimal TypeScript demo that uses the Poindexter WASM ESM loader.
+// Precondition: run `make wasm-build` at repo root, then `npm run dev` in this folder.
+
+// We copy the loader and wasm artifacts to /public via scripts/copy-assets.mjs before dev starts.
+// @ts-ignore
+import { init } from '/loader.js';
+
+async function run() {
+  const px = await init({
+    wasmURL: '/poindexter.wasm',
+    wasmExecURL: '/wasm_exec.js',
+  });
+
+  console.log('Poindexter (WASM) version:', await px.version());
+
+  const tree = await px.newTree(2);
+  await tree.insert({ id: 'a', coords: [0, 0], value: 'A' });
+  await tree.insert({ id: 'b', coords: [1, 0], value: 'B' });
+  await tree.insert({ id: 'c', coords: [0, 1], value: 'C' });
+
+  const nn = await tree.nearest([0.9, 0.1]);
+  console.log('Nearest [0.9,0.1]:', nn);
+
+  const kn = await tree.kNearest([0.9, 0.9], 2);
+  console.log('kNN k=2 [0.9,0.9]:', kn);
+
+  const rad = await tree.radius([0, 0], 1.1);
+  console.log('Radius r=1.1 [0,0]:', rad);
+}
+
+run().catch((err) => {
+  console.error('WASM demo error:', err);
+});
diff --git a/examples/wasm-browser-ts/tsconfig.json b/examples/wasm-browser-ts/tsconfig.json
new file mode 100644
index 0000000..1f26f35
--- /dev/null
+++ b/examples/wasm-browser-ts/tsconfig.json
@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "jsx": "react-jsx",
+    "allowJs": false,
+    "types": []
+  },
+  "include": ["src/**/*"]
+}
diff --git a/examples/wasm-browser-ts/vite.config.ts b/examples/wasm-browser-ts/vite.config.ts
new file mode 100644
index 0000000..cce1d7d
--- /dev/null
+++ b/examples/wasm-browser-ts/vite.config.ts
@@ -0,0 +1,17 @@
+import { defineConfig } from 'vite';
+
+// Minimal Vite config for the WASM TS example.
+// Serves files from project root; our dev script copies required artifacts to public/.
+export default defineConfig({
+  root: '.',
+  server: {
+    host: '127.0.0.1',
+    port: 5173,
+    open: false,
+  },
+  preview: {
+    host: '127.0.0.1',
+    port: 5173,
+    open: false,
+  },
+});
diff --git a/kdtree_helpers.go b/kdtree_helpers.go
index 9d16a78..298b000 100644
--- a/kdtree_helpers.go
+++ b/kdtree_helpers.go
@@ -88,6 +88,23 @@ func BuildND[T any](items []T, id func(T) string, features []func(T) float64, we
 	return BuildNDWithStats(items, id, features, weights, invert, stats)
 }
 
+// BuildNDNoErr constructs normalized-and-weighted KD points like BuildND but never returns an error.
+// It performs no input validation beyond basic length checks and will propagate NaN/Inf values
+// from feature extractors into the resulting coordinates. Use when you control inputs and want a
+// simpler call signature.
+func BuildNDNoErr[T any](items []T, id func(T) string, features []func(T) float64, weights []float64, invert []bool) []KDPoint[T] {
+	if len(items) == 0 || len(features) == 0 {
+		return nil
+	}
+	// If lengths are inconsistent, return empty (no panic); this function is intentionally lenient.
+	if len(weights) != len(features) || len(invert) != len(features) {
+		return nil
+	}
+	stats, _ := ComputeNormStatsND(items, features)
+	pts, _ := BuildNDWithStats(items, id, features, weights, invert, stats)
+	return pts
+}
+
 // BuildNDWithStats builds points using provided normalisation stats.
 func BuildNDWithStats[T any](items []T, id func(T) string, features []func(T) float64, weights []float64, invert []bool, stats NormStats) ([]KDPoint[T], error) {
 	if len(items) == 0 {
diff --git a/kdtree_nd_noerr_test.go b/kdtree_nd_noerr_test.go
new file mode 100644
index 0000000..a8711b7
--- /dev/null
+++ b/kdtree_nd_noerr_test.go
@@ -0,0 +1,63 @@
+package poindexter
+
+import (
+	"fmt"
+	"math"
+	"testing"
+)
+
+// TestBuildNDNoErr_Parity checks that BuildNDNoErr matches BuildND on valid inputs.
+func TestBuildNDNoErr_Parity(t *testing.T) {
+	type rec struct {
+		A, B, C float64
+		ID      string
+	}
+	items := []rec{
+		{A: 10, B: 100, C: 1, ID: "x"},
+		{A: 20, B: 200, C: 2, ID: "y"},
+		{A: 30, B: 300, C: 3, ID: "z"},
+	}
+	features := []func(rec) float64{
+		func(r rec) float64 { return r.A },
+		func(r rec) float64 { return r.B },
+		func(r rec) float64 { return r.C },
+	}
+	weights := []float64{1, 0.5, 2}
+	invert := []bool{false, true, false}
+	idfn := func(r rec) string { return r.ID }
+
+	ptsStrict, err := BuildND(items, idfn, features, weights, invert)
+	if err != nil {
+		t.Fatalf("BuildND returned error: %v", err)
+	}
+	ptsLoose := BuildNDNoErr(items, idfn, features, weights, invert)
+	if len(ptsStrict) != len(ptsLoose) {
+		t.Fatalf("length mismatch: strict %d loose %d", len(ptsStrict), len(ptsLoose))
+	}
+	for i := range ptsStrict {
+		if ptsStrict[i].ID != ptsLoose[i].ID {
+			t.Fatalf("ID mismatch at %d: %s vs %s", i, ptsStrict[i].ID, ptsLoose[i].ID)
+		}
+		if len(ptsStrict[i].Coords) != len(ptsLoose[i].Coords) {
+			t.Fatalf("dim mismatch at %d: %d vs %d", i, len(ptsStrict[i].Coords), len(ptsLoose[i].Coords))
+		}
+		for d := range ptsStrict[i].Coords {
+			if math.Abs(ptsStrict[i].Coords[d]-ptsLoose[i].Coords[d]) > 1e-12 {
+				t.Fatalf("coord mismatch at %d dim %d: %v vs %v", i, d, ptsStrict[i].Coords[d], ptsLoose[i].Coords[d])
+			}
+		}
+	}
+}
+
+// TestBuildNDNoErr_Lenient ensures the no-error builder is lenient and returns nil on bad lengths.
+func TestBuildNDNoErr_Lenient(t *testing.T) {
+	type rec struct{ A float64 }
+	items := []rec{{A: 1}, {A: 2}}
+	features := []func(rec) float64{func(r rec) float64 { return r.A }}
+	weightsBad := []float64{} // wrong length
+	invert := []bool{false}
+	pts := BuildNDNoErr(items, func(r rec) string { return fmt.Sprint(r.A) }, features, weightsBad, invert)
+	if pts != nil {
+		t.Fatalf("expected nil result on bad weights length, got %v", pts)
+	}
+}
diff --git a/npm/poindexter-wasm/smoke.mjs b/npm/poindexter-wasm/smoke.mjs
new file mode 100644
index 0000000..925a246
--- /dev/null
+++ b/npm/poindexter-wasm/smoke.mjs
@@ -0,0 +1,26 @@
+// Minimal Node smoke test for the WASM loader.
+// Assumes npm-pack has prepared npm/poindexter-wasm with loader and dist assets.
+
+import { init } from './loader.js';
+
+(async function () {
+  try {
+    const px = await init({
+      // In CI, dist/ is placed at repo root via make wasm-build && make npm-pack
+      wasmURL: new URL('./dist/poindexter.wasm', import.meta.url).pathname,
+      wasmExecURL: new URL('./dist/wasm_exec.js', import.meta.url).pathname,
+    });
+    const ver = await px.version();
+    if (!ver || typeof ver !== 'string') throw new Error('version not string');
+
+    const tree = await px.newTree(2);
+    await tree.insert({ id: 'a', coords: [0, 0], value: 'A' });
+    await tree.insert({ id: 'b', coords: [1, 0], value: 'B' });
+    const nn = await tree.nearest([0.9, 0.1]);
+    if (!nn || !nn.id) throw new Error('nearest failed');
+    console.log('WASM smoke ok:', ver, 'nearest.id=', nn.id);
+  } catch (err) {
+    console.error('WASM smoke failed:', err);
+    process.exit(1);
+  }
+})();