diff --git a/.eslintrc.json b/.eslintrc.json
deleted file mode 100644
index 81104c4..0000000
--- a/.eslintrc.json
+++ /dev/null
@@ -1,26 +0,0 @@
-{
-  "parserOptions": {
-    "ecmaVersion": 6,
-    "sourceType": "module"
-  },
-  "extends": "eslint:recommended",
-  "rules": {
-    "strict": [2, "global"],
-    "block-scoped-var": 2,
-    "consistent-return": 2,
-    "eqeqeq": [2, "smart"],
-    "guard-for-in": 2,
-    "no-caller": 2,
-    "no-extend-native": 2,
-    "no-loop-func": 2,
-    "no-new": 2,
-    "no-param-reassign": 2,
-    "no-return-assign": 2,
-    "no-unused-expressions": 2,
-    "no-use-before-define": 2,
-    "radix": [2, "always"],
-    "indent": [2, 2, { "SwitchCase": 1 }],
-    "quotes": [2, "double"],
-    "semi": [2, "always"]
-  }
-}
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c69237a..a1c4227 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,30 +6,18 @@ on:
   pull_request:
     branches: [master]
 
+permissions:
+  contents: read
+
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-
-      - uses: purescript-contrib/setup-purescript@main
-        with:
-          purescript: "unstable"
-
-      - uses: actions/setup-node@v2
+      - uses: actions/checkout@v6
+      - uses: actions/setup-node@v6
         with:
-          node-version: "14.x"
-
-      - name: Install dependencies
-        run: |
-          npm install -g bower
-          npm install
-          bower install --production
-
-      - name: Build source
-        run: npm run-script build
-
-      - name: Run tests
-        run: |
-          bower install
-          npm run-script test --if-present
+          node-version: "24"
+      - run: npm install
+      - run: npm run build
+      - run: npm run lint
+      - run: npm run format:check
diff --git a/.gitignore b/.gitignore
index b846b63..7ddb3b1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,10 @@
 /.*
 !/.gitignore
-!/.eslintrc.json
+!/.tidyrc.json
+!/.oxfmtrc.json
 !/.github/
 /bower_components/
 /node_modules/
 /output/
-package-lock.json
+/package-lock.json
+/spago.lock
diff --git a/.oxfmtrc.json b/.oxfmtrc.json
new file mode 100644
index 0000000..757fd64
--- /dev/null
+++ b/.oxfmtrc.json
@@ -0,0 +1,3 @@
+{
+  "trailingComma": "es5"
+}
diff --git a/.tidyrc.json b/.tidyrc.json
new file mode 100644
index 0000000..9e39cf1
--- /dev/null
+++ b/.tidyrc.json
@@ -0,0 +1,10 @@
+{
+  "importSort": "ide",
+  "importWrap": "source",
+  "indent": 2,
+  "operatorsFile": null,
+  "ribbon": 1,
+  "typeArrowPlacement": "first",
+  "unicode": "never",
+  "width": null
+}
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7427a2e..fdc0951 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 
 Notable changes to this project are documented in this file. The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [Unreleased](https://github.com/purescript/purescript-effect/compare/v4.0.1...HEAD)
 
 Breaking changes:
 
@@ -12,9 +12,22 @@ Bugfixes:
 
 Other improvements:
 
+## [v4.0.1](https://github.com/purescript/purescript-effect/releases/tag/v4.0.1) - 2026-10-17
+
+Breaking changes:
+
+New features:
+
+Bugfixes:
+
+Other improvements:
+
+- Migrate from Bower/Pulp to Spago and update CI and formatting/linting tools (#33 by @thomashoneyman)
+
 ## [v4.0.0](https://github.com/purescript/purescript-effect/releases/tag/v4.0.0) - 2022-04-27
 
 Breaking changes:
+
 - Migrate FFI to ES modules (#29 by @kl0tl and @JordanMartinez)
 
 New features:
@@ -26,18 +39,21 @@ Other improvements:
 ## [v3.0.0](https://github.com/purescript/purescript-effect/releases/tag/v3.0.0) - 2021-02-26
 
 Breaking changes:
-  - Added support for PureScript 0.14 and dropped support for all previous versions (#21)
+
+- Added support for PureScript 0.14 and dropped support for all previous versions (#21)
 
 New features:
-- Added roles declarations to allow safe coercions (#20) 
+
+- Added roles declarations to allow safe coercions (#20)
 - Added monoid instances for uncurried `EffectFn`s (#13)
 
 Bugfixes:
 
 Other improvements:
-  - Migrated CI to GitHub Actions and updated installation instructions to use Spago (#22)
-  - Added a CHANGELOG.md file and pull request template (#25, #26)
-  - Removed `return {}` from FFI functions for a small performance boost (#18)
+
+- Migrated CI to GitHub Actions and updated installation instructions to use Spago (#22)
+- Added a CHANGELOG.md file and pull request template (#25, #26)
+- Removed `return {}` from FFI functions for a small performance boost (#18)
 
 ## [v2.0.1](https://github.com/purescript/purescript-effect/releases/tag/v2.0.1) - 2019-01-26
 
@@ -52,6 +68,3 @@ Updated for PureScript 0.12
 - Added `Monoid` and `Semigroup` instances (@i-am-tom)
 
 ## [v1.0.0](https://github.com/purescript/purescript-effect/releases/tag/v1.0.0) - 2018-04-12
-
-
-
diff --git a/README.md b/README.md
index 14c9d33..7752565 100644
--- a/README.md
+++ b/README.md
@@ -158,11 +158,9 @@ var printRandom = function __do() {
 whereas a more naive compiler might, for instance, produce:
 
 ```javascript
-var printRandom = Control_Bind.bind(Effect.bindEffect)(Effect_Random.random)(
-  function ($0) {
-    return Effect_Console.log(Data_Show.show(Data_Show.showNumber)($0));
-  }
-);
+var printRandom = Control_Bind.bind(Effect.bindEffect)(Effect_Random.random)(function ($0) {
+  return Effect_Console.log(Data_Show.show(Data_Show.showNumber)($0));
+});
 ```
 
 While this is a small improvement, the benefit is greater when using
diff --git a/bower.json b/bower.json
deleted file mode 100644
index 3b520e6..0000000
--- a/bower.json
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-  "name": "purescript-effect",
-  "homepage": "https://github.com/purescript/purescript-effect",
-  "license": "BSD-3-Clause",
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/purescript/purescript-effect.git"
-  },
-  "ignore": [
-    "**/.*",
-    "bower_components",
-    "node_modules",
-    "output",
-    "test",
-    "bower.json",
-    "package.json"
-  ],
-  "dependencies": {
-    "purescript-prelude": "^6.0.0"
-  }
-}
diff --git a/package.json b/package.json
index 4ea39f9..8229f19 100644
--- a/package.json
+++ b/package.json
@@ -1,13 +1,22 @@
 {
   "private": true,
+  "homepage": "https://github.com/purescript/purescript-effect",
+  "license": "BSD-3-Clause",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/purescript/purescript-effect.git"
+  },
   "scripts": {
-    "clean": "rimraf output && rimraf .pulp-cache",
-    "build": "eslint src && pulp build -- --censor-lib --strict"
+    "build": "spago build",
+    "lint": "oxlint --deny-warnings src",
+    "format": "purs-tidy format-in-place src && oxfmt --write .",
+    "format:check": "purs-tidy check src && oxfmt --check ."
   },
   "devDependencies": {
-    "eslint": "^7.15.0",
-    "pulp": "16.0.0-0",
-    "purescript-psa": "^0.8.2",
-    "rimraf": "^3.0.2"
+    "oxfmt": "^0.73.0",
+    "oxlint": "^1.88.0",
+    "purescript": "^0.15.16",
+    "purs-tidy": "^0.11.1",
+    "spago": "^1.0.5"
   }
 }
diff --git a/spago.yaml b/spago.yaml
new file mode 100644
index 0000000..1f1bf21
--- /dev/null
+++ b/spago.yaml
@@ -0,0 +1,15 @@
+package:
+  name: effect
+  description: The Effect monad, for handling native side effects
+  build:
+    strict: true
+    pedanticPackages: true
+  publish:
+    version: 4.0.1
+    license: BSD-3-Clause
+    location:
+      githubOwner: purescript
+      githubRepo: purescript-effect
+  dependencies:
+    - prelude: ">=6.0.0 <7.0.0"
+workspace: {}
diff --git a/src/Effect.purs b/src/Effect.purs
index 32ea342..c3704ad 100644
--- a/src/Effect.purs
+++ b/src/Effect.purs
@@ -3,7 +3,10 @@
 -- | computations, while at the same time generating efficient JavaScript.
 module Effect
   ( Effect
-  , untilE, whileE, forE, foreachE
+  , untilE
+  , whileE
+  , forE
+  , foreachE
   ) where
 
 import Prelude
diff --git a/src/Effect/Uncurried.js b/src/Effect/Uncurried.js
index 09d4933..565df3f 100644
--- a/src/Effect/Uncurried.js
+++ b/src/Effect/Uncurried.js
@@ -1,75 +1,75 @@
 export const mkEffectFn1 = function mkEffectFn1(fn) {
-  return function(x) {
+  return function (x) {
     return fn(x)();
   };
 };
 
 export const mkEffectFn2 = function mkEffectFn2(fn) {
-  return function(a, b) {
+  return function (a, b) {
     return fn(a)(b)();
   };
 };
 
 export const mkEffectFn3 = function mkEffectFn3(fn) {
-  return function(a, b, c) {
+  return function (a, b, c) {
     return fn(a)(b)(c)();
   };
 };
 
 export const mkEffectFn4 = function mkEffectFn4(fn) {
-  return function(a, b, c, d) {
+  return function (a, b, c, d) {
     return fn(a)(b)(c)(d)();
   };
 };
 
 export const mkEffectFn5 = function mkEffectFn5(fn) {
-  return function(a, b, c, d, e) {
+  return function (a, b, c, d, e) {
     return fn(a)(b)(c)(d)(e)();
   };
 };
 
 export const mkEffectFn6 = function mkEffectFn6(fn) {
-  return function(a, b, c, d, e, f) {
+  return function (a, b, c, d, e, f) {
     return fn(a)(b)(c)(d)(e)(f)();
   };
 };
 
 export const mkEffectFn7 = function mkEffectFn7(fn) {
-  return function(a, b, c, d, e, f, g) {
+  return function (a, b, c, d, e, f, g) {
     return fn(a)(b)(c)(d)(e)(f)(g)();
   };
 };
 
 export const mkEffectFn8 = function mkEffectFn8(fn) {
-  return function(a, b, c, d, e, f, g, h) {
+  return function (a, b, c, d, e, f, g, h) {
     return fn(a)(b)(c)(d)(e)(f)(g)(h)();
   };
 };
 
 export const mkEffectFn9 = function mkEffectFn9(fn) {
-  return function(a, b, c, d, e, f, g, h, i) {
+  return function (a, b, c, d, e, f, g, h, i) {
     return fn(a)(b)(c)(d)(e)(f)(g)(h)(i)();
   };
 };
 
 export const mkEffectFn10 = function mkEffectFn10(fn) {
-  return function(a, b, c, d, e, f, g, h, i, j) {
+  return function (a, b, c, d, e, f, g, h, i, j) {
     return fn(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)();
   };
 };
 
 export const runEffectFn1 = function runEffectFn1(fn) {
-  return function(a) {
-    return function() {
+  return function (a) {
+    return function () {
       return fn(a);
     };
   };
 };
 
 export const runEffectFn2 = function runEffectFn2(fn) {
-  return function(a) {
-    return function(b) {
-      return function() {
+  return function (a) {
+    return function (b) {
+      return function () {
         return fn(a, b);
       };
     };
@@ -77,10 +77,10 @@ export const runEffectFn2 = function runEffectFn2(fn) {
 };
 
 export const runEffectFn3 = function runEffectFn3(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function () {
           return fn(a, b, c);
         };
       };
@@ -89,11 +89,11 @@ export const runEffectFn3 = function runEffectFn3(fn) {
 };
 
 export const runEffectFn4 = function runEffectFn4(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function () {
             return fn(a, b, c, d);
           };
         };
@@ -103,12 +103,12 @@ export const runEffectFn4 = function runEffectFn4(fn) {
 };
 
 export const runEffectFn5 = function runEffectFn5(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function () {
               return fn(a, b, c, d, e);
             };
           };
@@ -119,13 +119,13 @@ export const runEffectFn5 = function runEffectFn5(fn) {
 };
 
 export const runEffectFn6 = function runEffectFn6(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function(f) {
-              return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function (f) {
+              return function () {
                 return fn(a, b, c, d, e, f);
               };
             };
@@ -137,14 +137,14 @@ export const runEffectFn6 = function runEffectFn6(fn) {
 };
 
 export const runEffectFn7 = function runEffectFn7(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function(f) {
-              return function(g) {
-                return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function (f) {
+              return function (g) {
+                return function () {
                   return fn(a, b, c, d, e, f, g);
                 };
               };
@@ -157,15 +157,15 @@ export const runEffectFn7 = function runEffectFn7(fn) {
 };
 
 export const runEffectFn8 = function runEffectFn8(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function(f) {
-              return function(g) {
-                return function(h) {
-                  return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function (f) {
+              return function (g) {
+                return function (h) {
+                  return function () {
                     return fn(a, b, c, d, e, f, g, h);
                   };
                 };
@@ -179,16 +179,16 @@ export const runEffectFn8 = function runEffectFn8(fn) {
 };
 
 export const runEffectFn9 = function runEffectFn9(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function(f) {
-              return function(g) {
-                return function(h) {
-                  return function(i) {
-                    return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function (f) {
+              return function (g) {
+                return function (h) {
+                  return function (i) {
+                    return function () {
                       return fn(a, b, c, d, e, f, g, h, i);
                     };
                   };
@@ -203,17 +203,17 @@ export const runEffectFn9 = function runEffectFn9(fn) {
 };
 
 export const runEffectFn10 = function runEffectFn10(fn) {
-  return function(a) {
-    return function(b) {
-      return function(c) {
-        return function(d) {
-          return function(e) {
-            return function(f) {
-              return function(g) {
-                return function(h) {
-                  return function(i) {
-                    return function(j) {
-                      return function() {
+  return function (a) {
+    return function (b) {
+      return function (c) {
+        return function (d) {
+          return function (e) {
+            return function (f) {
+              return function (g) {
+                return function (h) {
+                  return function (i) {
+                    return function (j) {
+                      return function () {
                         return fn(a, b, c, d, e, f, g, h, i, j);
                       };
                     };
diff --git a/src/Effect/Uncurried.purs b/src/Effect/Uncurried.purs
index 7ed42e8..61ad98a 100644
--- a/src/Effect/Uncurried.purs
+++ b/src/Effect/Uncurried.purs
@@ -175,47 +175,160 @@ foreign import data EffectFn10 :: Type -> Type -> Type -> Type -> Type -> Type -
 
 type role EffectFn10 representational representational representational representational representational representational representational representational representational representational representational
 
-foreign import mkEffectFn1 :: forall a r.
-  (a -> Effect r) -> EffectFn1 a r
-foreign import mkEffectFn2 :: forall a b r.
-  (a -> b -> Effect r) -> EffectFn2 a b r
-foreign import mkEffectFn3 :: forall a b c r.
-  (a -> b -> c -> Effect r) -> EffectFn3 a b c r
-foreign import mkEffectFn4 :: forall a b c d r.
-  (a -> b -> c -> d -> Effect r) -> EffectFn4 a b c d r
-foreign import mkEffectFn5 :: forall a b c d e r.
-  (a -> b -> c -> d -> e -> Effect r) -> EffectFn5 a b c d e r
-foreign import mkEffectFn6 :: forall a b c d e f r.
-  (a -> b -> c -> d -> e -> f -> Effect r) -> EffectFn6 a b c d e f r
-foreign import mkEffectFn7 :: forall a b c d e f g r.
-  (a -> b -> c -> d -> e -> f -> g -> Effect r) -> EffectFn7 a b c d e f g r
-foreign import mkEffectFn8 :: forall a b c d e f g h r.
-  (a -> b -> c -> d -> e -> f -> g -> h -> Effect r) -> EffectFn8 a b c d e f g h r
-foreign import mkEffectFn9 :: forall a b c d e f g h i r.
-  (a -> b -> c -> d -> e -> f -> g -> h -> i -> Effect r) -> EffectFn9 a b c d e f g h i r
-foreign import mkEffectFn10 :: forall a b c d e f g h i j r.
-  (a -> b -> c -> d -> e -> f -> g -> h -> i -> j -> Effect r) -> EffectFn10 a b c d e f g h i j r
-
-foreign import runEffectFn1 :: forall a r.
-  EffectFn1 a r -> a -> Effect r
-foreign import runEffectFn2 :: forall a b r.
-  EffectFn2 a b r -> a -> b -> Effect r
-foreign import runEffectFn3 :: forall a b c r.
-  EffectFn3 a b c r -> a -> b -> c -> Effect r
-foreign import runEffectFn4 :: forall a b c d r.
-  EffectFn4 a b c d r -> a -> b -> c -> d -> Effect r
-foreign import runEffectFn5 :: forall a b c d e r.
-  EffectFn5 a b c d e r -> a -> b -> c -> d -> e -> Effect r
-foreign import runEffectFn6 :: forall a b c d e f r.
-  EffectFn6 a b c d e f r -> a -> b -> c -> d -> e -> f -> Effect r
-foreign import runEffectFn7 :: forall a b c d e f g r.
-  EffectFn7 a b c d e f g r -> a -> b -> c -> d -> e -> f -> g -> Effect r
-foreign import runEffectFn8 :: forall a b c d e f g h r.
-  EffectFn8 a b c d e f g h r -> a -> b -> c -> d -> e -> f -> g -> h -> Effect r
-foreign import runEffectFn9 :: forall a b c d e f g h i r.
-  EffectFn9 a b c d e f g h i r -> a -> b -> c -> d -> e -> f -> g -> h -> i -> Effect r
-foreign import runEffectFn10 :: forall a b c d e f g h i j r.
-  EffectFn10 a b c d e f g h i j r -> a -> b -> c -> d -> e -> f -> g -> h -> i -> j -> Effect r
+foreign import mkEffectFn1
+  :: forall a r
+   . (a -> Effect r)
+  -> EffectFn1 a r
+
+foreign import mkEffectFn2
+  :: forall a b r
+   . (a -> b -> Effect r)
+  -> EffectFn2 a b r
+
+foreign import mkEffectFn3
+  :: forall a b c r
+   . (a -> b -> c -> Effect r)
+  -> EffectFn3 a b c r
+
+foreign import mkEffectFn4
+  :: forall a b c d r
+   . (a -> b -> c -> d -> Effect r)
+  -> EffectFn4 a b c d r
+
+foreign import mkEffectFn5
+  :: forall a b c d e r
+   . (a -> b -> c -> d -> e -> Effect r)
+  -> EffectFn5 a b c d e r
+
+foreign import mkEffectFn6
+  :: forall a b c d e f r
+   . (a -> b -> c -> d -> e -> f -> Effect r)
+  -> EffectFn6 a b c d e f r
+
+foreign import mkEffectFn7
+  :: forall a b c d e f g r
+   . (a -> b -> c -> d -> e -> f -> g -> Effect r)
+  -> EffectFn7 a b c d e f g r
+
+foreign import mkEffectFn8
+  :: forall a b c d e f g h r
+   . (a -> b -> c -> d -> e -> f -> g -> h -> Effect r)
+  -> EffectFn8 a b c d e f g h r
+
+foreign import mkEffectFn9
+  :: forall a b c d e f g h i r
+   . (a -> b -> c -> d -> e -> f -> g -> h -> i -> Effect r)
+  -> EffectFn9 a b c d e f g h i r
+
+foreign import mkEffectFn10
+  :: forall a b c d e f g h i j r
+   . (a -> b -> c -> d -> e -> f -> g -> h -> i -> j -> Effect r)
+  -> EffectFn10 a b c d e f g h i j r
+
+foreign import runEffectFn1
+  :: forall a r
+   . EffectFn1 a r
+  -> a
+  -> Effect r
+
+foreign import runEffectFn2
+  :: forall a b r
+   . EffectFn2 a b r
+  -> a
+  -> b
+  -> Effect r
+
+foreign import runEffectFn3
+  :: forall a b c r
+   . EffectFn3 a b c r
+  -> a
+  -> b
+  -> c
+  -> Effect r
+
+foreign import runEffectFn4
+  :: forall a b c d r
+   . EffectFn4 a b c d r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> Effect r
+
+foreign import runEffectFn5
+  :: forall a b c d e r
+   . EffectFn5 a b c d e r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> Effect r
+
+foreign import runEffectFn6
+  :: forall a b c d e f r
+   . EffectFn6 a b c d e f r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> f
+  -> Effect r
+
+foreign import runEffectFn7
+  :: forall a b c d e f g r
+   . EffectFn7 a b c d e f g r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> f
+  -> g
+  -> Effect r
+
+foreign import runEffectFn8
+  :: forall a b c d e f g h r
+   . EffectFn8 a b c d e f g h r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> f
+  -> g
+  -> h
+  -> Effect r
+
+foreign import runEffectFn9
+  :: forall a b c d e f g h i r
+   . EffectFn9 a b c d e f g h i r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> f
+  -> g
+  -> h
+  -> i
+  -> Effect r
+
+foreign import runEffectFn10
+  :: forall a b c d e f g h i j r
+   . EffectFn10 a b c d e f g h i j r
+  -> a
+  -> b
+  -> c
+  -> d
+  -> e
+  -> f
+  -> g
+  -> h
+  -> i
+  -> j
+  -> Effect r
 
 -- The reason these are written eta-expanded instead of as:
 -- ```