diff --git a/pkg/universe.dagger.io/bash/bash.cue b/pkg/universe.dagger.io/bash/bash.cue
index ba694e99..afd3d50f 100644
--- a/pkg/universe.dagger.io/bash/bash.cue
+++ b/pkg/universe.dagger.io/bash/bash.cue
@@ -2,25 +2,59 @@
 package bash
 
 import (
+	"dagger.io/dagger"
+	"dagger.io/dagger/engine"
+
 	"universe.dagger.io/docker"
 )
 
-// Run a bash command or script in a container
+// Run a bash script in a Docker container
+//  Since this is a thin wrapper over docker.#Run, we embed it.
+//  Whether to embed or wrap is a case-by-case decision, like in Go.
 #Run: {
-	// Contents of the bash script
-	script: string
+	// The script to execute
+	script: {
+		// A directory containing one or more bash scripts
+		directory: dagger.#FS
+
+		// Name of the file to execute
+		filename: string
+
+		_directory: directory
+		_filename:  filename
+	} | {
+		// Script contents
+		contents: string
+
+		_filename: "run.sh"
+		_write:    engine.#WriteFile & {
+			input:      engine.#Scratch
+			path:       _filename
+			"contents": contents
+		}
+		_directory: _write.output
+	}
+
+	// Arguments to the script
+	args: [...string]
+
+	// Where in the container to mount the scripts directory
+	_mountpoint: "/bash/scripts"
 
-	// FIXME: don't pass the script as argument: write to filesystme instead
 	docker.#Run & {
 		command: {
-			name: "bash"
+			name:   "bash"
+			"args": ["\(_mountpoint)/\(script._filename)"] + args
+			// FIXME: make default flags overrideable
 			flags: {
-				"-c":          script
-				"--noprofile": true
-				"--norc":      true
-				"-e":          true
-				"-o":          "pipefail"
+				"--norc": true
+				"-e":     true
+				"-o":     "pipefail"
 			}
 		}
+		mounts: "Bash scripts": {
+			contents: script._directory
+			dest:     _mountpoint
+		}
 	}
 }
diff --git a/pkg/universe.dagger.io/bash/test/bash.bats b/pkg/universe.dagger.io/bash/test/bash.bats
new file mode 100644
index 00000000..42186abf
--- /dev/null
+++ b/pkg/universe.dagger.io/bash/test/bash.bats
@@ -0,0 +1,10 @@
+setup() {
+    load '../../bats_helpers'
+
+    common_setup
+}
+
+@test "bash.#Run" {
+    dagger up ./run-simple
+}
+
diff --git a/pkg/universe.dagger.io/bash/test/run-simple/hello.sh b/pkg/universe.dagger.io/bash/test/run-simple/hello.sh
new file mode 100644
index 00000000..2bf977e9
--- /dev/null
+++ b/pkg/universe.dagger.io/bash/test/run-simple/hello.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+echo Hello, world > /out.txt
diff --git a/pkg/universe.dagger.io/bash/test/run-simple/simple.cue b/pkg/universe.dagger.io/bash/test/run-simple/simple.cue
new file mode 100644
index 00000000..3227b9b0
--- /dev/null
+++ b/pkg/universe.dagger.io/bash/test/run-simple/simple.cue
@@ -0,0 +1,87 @@
+package bash
+
+import (
+	"dagger.io/dagger"
+
+	"universe.dagger.io/docker"
+	"universe.dagger.io/alpine"
+)
+
+dagger.#DAG & {
+	actions: {
+		"Run from source directory": {
+			build: alpine.#Build & {
+				packages: bash: _
+			}
+			run: #Run & {
+				image: build.output
+				script: {
+					directory: loadScripts.output
+					filename:  "hello.sh"
+				}
+				export: files: "/out.txt": _
+			}
+			output: run.export.files."/out.txt".contents & "Hello, world\n"
+		}
+
+		"Run from source directory with custom image": {
+			debian: docker.#Pull & {
+				source: "index.docker.io/debian"
+			}
+			run: #Run & {
+				image: debian.output
+				export: files: "/out.txt": _
+				script: {
+					directory: loadScripts.output
+					filename:  "hello.sh"
+				}
+			}
+			output: run.export.files."/out.txt".contents & "Hello, world\n"
+		}
+
+		"Run from string": {
+			run: #Run & {
+				script: contents: "echo 'Hello, inlined world!' > /output.txt"
+				export: files: "/output.txt": _
+			}
+			output: run.export.files."/output.txt".contents & "Hello, inlined world!\n"
+		}
+
+		"Run from string with custom image": {
+			debian: docker.#Pull & {
+				source: "index.docker.io/debian"
+			}
+			run: #Run & {
+				image: debian.output
+				export: files: "/output.txt": _
+				script: contents: "echo 'Hello, inlined world!' > /output.txt"
+			}
+			output: run.export.files."/output.txt".contents & "Hello, inlined world!\n"
+		}
+
+		// Same thing but without bash.#Run
+		control: {
+			run: docker.#Run & {
+				image: base.output
+				command: {
+					name: "sh"
+					args: ["/bash/scripts/hello.sh"]
+				}
+				mounts: scripts: {
+					contents: loadScripts.output
+					dest:     "/bash/scripts"
+				}
+				export: files: "/out.txt": _
+			}
+			output: run.export.files."/out.txt".contents & "Hello, world\n"
+			base:   docker.#Pull & {
+				source: "alpine"
+			}
+		}
+
+		loadScripts: dagger.#Source & {
+			path: "."
+			include: ["*.sh"]
+		}
+	}
+}
diff --git a/pkg/universe.dagger.io/netlify/netlify.cue b/pkg/universe.dagger.io/netlify/netlify.cue
index bc278481..f526fd67 100644
--- a/pkg/universe.dagger.io/netlify/netlify.cue
+++ b/pkg/universe.dagger.io/netlify/netlify.cue
@@ -4,9 +4,11 @@ package netlify
 
 import (
 	"dagger.io/dagger"
+	"dagger.io/dagger/engine"
 
 	"universe.dagger.io/alpine"
 	"universe.dagger.io/docker"
+	"universe.dagger.io/bash"
 )
 
 // Deploy a site to Netlify
@@ -34,12 +36,7 @@ import (
 	// Create the site if it doesn't exist
 	create: *true | false
 
-	// Source code of the Netlify package
-	_source: dagger.#Source & {
-		path: "."
-		include: ["*.sh"]
-	}
-
+	// Build a docker image to run the netlify client
 	_build: docker.#Build & {
 		steps: [
 			alpine.#Build & {
@@ -50,45 +47,26 @@ import (
 					yarn: {}
 				}
 			},
+			// FIXME: make this an alpine custom package, that would be so cool.
 			docker.#Run & {
 				command: {
 					name: "yarn"
 					args: ["global", "add", "netlify-cli@8.6.21"]
 				}
 			},
-			docker.#Copy & {
-				contents: _source.output
-				dest:     "/app"
-			},
 		]
 	}
 
-	// Execute `netlify deploy` in a container
-	command: docker.#Run & {
-		// FIXME: custom base image not supported
-		// Container image. `netlify` must be available in the execution path
-		// *{
-		//  _buildDefaultImage: docker.#Build & {
-		//   input: alpine.#Build & {
-		//    bash: version: "=~5.1"
-		//    jq: version:   "=~1.6"
-		//    curl: {}
-		//    yarn: version: "=~1.22"
-		//   }
-		//   steps: [{
-		//    run: command: {
-		//      name: "sh"
-		//      flags: "-c": "yarn global add netlify-cli@3.38.10"
-		//    }
-		//   }]
-		//  }
-
-		//  // No nested tasks, boo hoo hoo
-		//  image: _buildDefaultImage.output
-		//  env: CUSTOM_IMAGE: "0"
-		// } | {
-		//  env: CUSTOM_IMAGE: "1"
-		// }
+	// Run the netlify client in a container
+	container: bash.#Run & {
+		script: {
+			_load: engine.#Source & {
+				path: "."
+				include: ["*.sh"]
+			}
+			directory: _load.output
+			filename:  "deploy.sh"
+		}
 
 		image: _build.output
 
@@ -114,7 +92,6 @@ import (
 				contents: token
 			}
 		}
-		command: name: "/app/deploy.sh"
 
 		export: files: {
 			"/netlify/url":       _
@@ -124,11 +101,11 @@ import (
 	}
 
 	// URL of the deployed site
-	url: command.export.files."/netlify/url".contents
+	url: container.export.files."/netlify/url".contents
 
 	// URL of the latest deployment
-	deployUrl: command.export.files."/netlify/deployUrl".contents
+	deployUrl: container.export.files."/netlify/deployUrl".contents
 
 	// URL for logs of the latest deployment
-	logsUrl: command.export.files."/netlify/logsUrl".contents
+	logsUrl: container.export.files."/netlify/logsUrl".contents
 }
diff --git a/pkg/universe.dagger.io/netlify/test/netlify-test.cue b/pkg/universe.dagger.io/netlify/test/netlify-test.cue
index 33658e6e..4de4864d 100644
--- a/pkg/universe.dagger.io/netlify/test/netlify-test.cue
+++ b/pkg/universe.dagger.io/netlify/test/netlify-test.cue
@@ -47,8 +47,8 @@ dagger.#Plan & {
 
 		// Check if the website was deployed
 		verify: bash.#Run & {
-			input:  image.output
-			script: #"""
+			input: image.output
+			script: contents: #"""
 			  test "$(curl \#(deploy.deployUrl))" = "\#(marker)"
 			  """#
 		}
diff --git a/pkg/universe.dagger.io/yarn/test/yarn-test.cue b/pkg/universe.dagger.io/yarn/test/yarn-test.cue
index d35d535f..aaacb5ae 100644
--- a/pkg/universe.dagger.io/yarn/test/yarn-test.cue
+++ b/pkg/universe.dagger.io/yarn/test/yarn-test.cue
@@ -33,7 +33,7 @@ dagger.#Plan & {
 				dest:     "/build"
 				contents: pkg.output
 			}
-			script: #"""
+			script: contents: #"""
 				test "$(cat /build/test)" = "output"
 				"""#
 		}
diff --git a/pkg/universe.dagger.io/yarn/yarn.cue b/pkg/universe.dagger.io/yarn/yarn.cue
index 46e34b7e..ae6b813b 100644
--- a/pkg/universe.dagger.io/yarn/yarn.cue
+++ b/pkg/universe.dagger.io/yarn/yarn.cue
@@ -48,33 +48,19 @@ import (
 	// yarnVersion: *"=~1.22" | string
 
 	// FIXME: custom base image not supported
-	image: alpine.#Build & {
+	_buildImage: alpine.#Build & {
 		packages: {
 			bash: {}
 			yarn: {}
 		}
 	}
 
-	// Run yarn in a containerized build environment
-	command: bash.#Run & {
-		// FIXME: not working?
-		// *{
-		//  _image: alpine.#Build & {
-		//   packages: {
-		//    bash: version: "=~5.1"
-		//    yarn: version: yarnVersion
-		//   }
-		//  }
+	// Run yarn in a docker container
+	container: bash.#Run & {
+		image: _buildImage.output
 
-		//  image: _image.output
-		//  env: CUSTOM_IMAGE: "0"
-		// } | {
-		//  env: CUSTOM_IMAGE: "1"
-		// }
-
-		"image": image.output
-
-		script: #"""
+		// FIXME: move shell script to its own file
+		script: contents: #"""
 			# Create $ENVFILE_NAME file if set
 			[ -n "$ENVFILE_NAME" ] && echo "$ENVFILE" > "$ENVFILE_NAME"
 
@@ -94,7 +80,6 @@ import (
 				dest:     "/src"
 				contents: source
 			}
-			// FIXME: mount secrets
 		}
 
 		export: directories: "/build": _
@@ -115,5 +100,5 @@ import (
 	}
 
 	// The final contents of the package after build
-	output: command.export.directories."/build".contents
+	output: container.export.directories."/build".contents
 }