diff --git a/pkgs/development/python-modules/viser/default.nix b/pkgs/development/python-modules/viser/default.nix
index 32338fb25d3a..1e06627196aa 100644
--- a/pkgs/development/python-modules/viser/default.nix
+++ b/pkgs/development/python-modules/viser/default.nix
@@ -6,8 +6,8 @@
 
   # nativeBuildInputs
   nodejs,
-  fetchYarnDeps,
-  yarnConfigHook,
+  fetchNpmDeps,
+  npmHooks,
 
   # build-system
   hatchling,
@@ -15,79 +15,78 @@
   # dependencies
   imageio,
   msgspec,
-  nodeenv,
   numpy,
-  opencv-python,
-  plyfile,
-  psutil,
   requests,
   rich,
-  scikit-image,
-  scipy,
   tqdm,
   trimesh,
   typing-extensions,
   websockets,
   yourdfpy,
+  zstandard,
 
   # optional-dependencies
   hypothesis,
+  liblzfse,
+  nodeenv,
+  opencv-python,
+  playwright,
   pre-commit,
-  pandas,
+  psutil,
   pyright,
   pytest,
+  pytest-playwright,
+  pytest-xdist,
   ruff,
   gdown,
   matplotlib,
+  pandas,
   plotly,
-  # pyliblzfse,
+  plyfile,
   robot-descriptions,
   torch,
   tyro,
 
   # nativeCheckInputs
   pytestCheckHook,
+  playwright-driver,
 }:
 
 buildPythonPackage (finalAttrs: {
   pname = "viser";
-  version = "1.0.20";
+  version = "1.0.26";
   pyproject = true;
 
   src = fetchFromGitHub {
     owner = "viser-project";
     repo = "viser";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-usnvEvuBNPrqRXV7jh0qw1ppmZgAe1CUhAwd/M5CvC0=";
+    hash = "sha256-qmHgjXBTJB0ka+QM+wmiUIXS+upeH3MxjAU9wHePWMY=";
   };
 
   postPatch = ''
-    # prepare yarn offline cache
+    # prepare npm offline cache
     mkdir -p node_modules
     cd src/viser/client
-    cp package.json yarn.lock ../../..
+    cp package.json package-lock.json ../../..
     ln -s ../../../node_modules
-
-    # fix: [vite-plugin-eslint] Failed to load config "react-app" to extend from.
-    substituteInPlace vite.config.mts --replace-fail \
-      "eslint({ failOnError: false, failOnWarning: false })," ""
-
     cd ../../..
   '';
 
   nativeBuildInputs = [
-    yarnConfigHook
+    npmHooks.npmConfigHook
     nodejs
   ];
 
-  yarnOfflineCache = fetchYarnDeps {
-    yarnLock = finalAttrs.src + "/src/viser/client/yarn.lock";
-    hash = "sha256-4x+zJIqjVoKmEdOUPGpCuMmlRBfF++3oWtbNYAvd2ko=";
+  npmDeps = fetchNpmDeps {
+    name = "${finalAttrs.pname}-${finalAttrs.version}-npm-deps";
+    src = finalAttrs.src + "/src/viser/client/";
+    hash = "sha256-pV8xc+dQA8Z2EpQoIxzUlH2cZJoGKB03cP6GglGdn58=";
   };
 
   preBuild = ''
     cd src/viser/client
-    yarn --offline build
+    npm --offline run build
     cd ../../..
   '';
 
@@ -98,37 +97,39 @@ buildPythonPackage (finalAttrs: {
   dependencies = [
     imageio
     msgspec
-    nodeenv
     numpy
-    opencv-python
-    plyfile
-    psutil
     requests
     rich
-    scikit-image
-    scipy
     tqdm
     trimesh
     typing-extensions
     websockets
     yourdfpy
+    zstandard
   ];
 
   optional-dependencies = {
     dev = [
       hypothesis
+      nodeenv
+      opencv-python
+      playwright
       pre-commit
+      psutil
       pyright
       pytest
+      pytest-playwright
+      pytest-xdist
       ruff
     ];
     examples = [
       gdown
+      liblzfse
       matplotlib
+      opencv-python
       pandas
       plotly
       plyfile
-      # pyliblzfse
       robot-descriptions
       torch
       tyro
@@ -137,17 +138,61 @@ buildPythonPackage (finalAttrs: {
 
   nativeCheckInputs = [
     hypothesis
+    playwright-driver
     pytestCheckHook
   ];
 
+  checkInputs = finalAttrs.passthru.optional-dependencies.dev;
+
+  env = {
+    PLAYWRIGHT_BROWSERS_PATH = playwright-driver.browsers;
+    PLAYWRIGHT_SKIP_BROWSER_DOWNLOAD = true;
+    PLAYWRIGHT_SKIP_VALIDATE_HOST_REQUIREMENTS = true;
+  };
+
+  disabledTests = [
+    # AssertionError: Locator expected to be visible
+    "test_modal_renders_with_content[chromium]"
+    "test_rgb_color_picker_renders[chromium]"
+    "test_rgb_server_update[chromium]"
+    "test_rgba_color_picker_renders[chromium]"
+    "test_vector2_renders[chromium]"
+    "test_vector2_initial_values[chromium]"
+    "test_vector3_renders[chromium]"
+    "test_vector3_server_update[chromium]"
+    "test_slider_renders[chromium]"
+    "test_text_input_renders_with_value[chromium]"
+    "test_number_input_renders[chromium]"
+    "test_dropdown_renders[chromium]"
+    "test_dropdown_with_initial_value[chromium]"
+    "test_markdown_renders[chromium]"
+    "test_folder_renders_and_contains_children[chromium]"
+    "test_folder_collapse_toggle[chromium]"
+    "test_server_updates_text_value[chromium]"
+    "test_text_input_change_callback[chromium]"
+    "test_dropdown_selection_callback[chromium]"
+    "test_server_value_update_round_trip[chromium]"
+
+    # playwright._impl._errors.TimeoutError: Locator.wait_for: Timeout 5000ms exceeded.
+    # (same issue with 20s)
+    "test_long_underscore_label_wraps_within_container[chromium]"
+
+    # AssertionError: Locator expected to have Value 'initial'
+    "test_gui_state_sync_text[chromium]"
+
+    # assert 0 != 0
+    # (only when xdist)
+    "test_server_port_is_freed"
+  ];
+
   pythonImportsCheck = [
     "viser"
   ];
 
   meta = {
     changelog = "https://github.com/viser-project/viser/releases/tag/${finalAttrs.src.tag}";
-    description = "Web-based 3D visualization + Python";
-    homepage = "https://github.com/nerfstudio-project/viser";
+    description = "Web-based 3D visualization in Python";
+    homepage = "https://github.com/viser-project/viser";
     license = lib.licenses.asl20;
     maintainers = with lib.maintainers; [ nim65s ];
   };