diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..6c629d3
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,18 @@
+# Changelog
+
+All notable changes to this project will be documented in this file. The format
+is based on [Keep a Changelog].
+
+This project adheres to [Semantic Versioning].
+
+## [Unreleased]
+
+## [1.0.0] - 2022-04-07
+
+Initial public release.
+
+[Unreleased]:   https://github.com/waldoapp/waldo-go-lib/compare/v1.0.0...HEAD
+[1.0.0]:        https://github.com/waldoapp/waldo-go-lib/compare/81e8b45...v1.0.0
+
+[Keep a Changelog]:     https://keepachangelog.com
+[Semantic Versioning]:  https://semver.org
diff --git a/README.md b/README.md
index 224037e..7b24727 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,76 @@
 # waldoapp/gh-action-upload
+
+This GitHub Action uploads your build (`.app`, `.ipa`, or `.apk`) to Waldo.
+
+You must specify at least a build path and a Waldo upload token.
+
+Typically the build path is generated by a previous build action in your
+workflow.
+
+Each application registered in Waldo is associated with a unique upload token.
+You can find the upload token for your app by going to the Documentation screen
+for your app in [Waldo](https://app.waldo.io/). This token _should_ be
+specified as a _secret_ environment variable. 
+
+## Inputs
+
+- `build_path`
+
+  The path to your `.app`, `.ipa`, or `.apk` build. Typically the build path is
+  generated by a previous build action in your workflow. **Required.**
+
+- `upload_token`
+
+  The upload token associated with your app. Each application registered in
+  Waldo is associated with a unique upload token. **Required.**
+
+- `variant_name`
+
+  An optional variant name. This is an arbitrary string to associate with this
+  build.
+
+- `git_commit`
+
+  The originating git commit hash. This is the hash of the originating git
+  commit (also known as the “git SHA”) for this build. If omitted, Waldo
+  attempts to infer the git commit from the CI provider (if any) or from the
+  current git repository (if accessible).
+
+- `git_branch`
+
+  The originating git commit branch name. This is the branch name (if any) of
+  the originating git commit for this build. If omitted, Waldo attempts to
+  infer the git branch name from the CI provider (if any) or from the current
+  git repository (if accessible).
+
+- `is_debug_mode`
+
+  If this mode is enabled, additional debug information is printed. (Default:
+  `false`.)
+
+## Usage
+
+```yaml
+steps:
+  - name: Checkout
+    uses: actions/checkout@v2
+    with:
+      fetch-depth: 0
+  - name: Build with Xcode
+    run: |
+      DERIVED_DATA_PATH=/tmp/YourApp-$(uuidgen)
+
+      xcodebuild -project YourApp.xcodeproj                     \
+                 -scheme YourApp                                \
+                 -configuration Release                         \
+                 -destination 'generic/platform=iOS Simulator'  \
+                 -derivedDataPath "$DERIVED_DATA_PATH"          \
+                 clean build
+
+      echo "APP_DIR_PATH=${DERIVED_DATA_PATH}/Build/Products/Release-iphonesimulator/YourApp.app" >>$GITHUB_ENV
+  - name: Upload build to Waldo
+    uses: waldoapp/gh-action-upload@v1
+    with:
+      build_path: ${{ env.APP_DIR_PATH }}
+      upload_token: ${{ secrets.WALDO_UPLOAD_TOKEN }}
+```
diff --git a/action.yml b/action.yml
new file mode 100644
index 0000000..55a7d06
--- /dev/null
+++ b/action.yml
@@ -0,0 +1,84 @@
+name: 'Upload to Waldo'
+description: |
+  Uploads your build (`.app`, `.ipa`, or `.apk`) to Waldo.
+inputs:
+  build_path:
+    description: >
+      The path to your `.app`, `.ipa`, or `.apk` build. Typically the build
+      path is generated by a previous build action in your workflow.
+    required: true
+  upload_token:
+    description: >
+      The upload token associated with your app. Each application registered in
+      Waldo is associated with a unique upload token.
+    required: true
+  variant_name:
+    description: >
+      An optional variant name. This is an arbitrary string to associate with
+      this build.
+    required: false
+    default: ''
+  git_commit:
+    description: >
+      The originating git commit hash. This is the hash of the originating git
+      commit (also known as the “git SHA”) for this build. If omitted, Waldo
+      attempts to infer the git commit from the CI provider (if any) or from
+      the current git repository (if accessible).
+    required: false
+    default: ''
+  git_branch:
+    description: >
+      The originating git commit branch name. This is the branch name (if any)
+      of the originating git commit for this build. If omitted, Waldo attempts
+      to infer the git branch name from the CI provider (if any) or from the
+      current git repository (if accessible).
+    required: false
+    default: ''
+  is_debug_mode:
+    description: >
+      If this mode is enabled, additional debug information is printed.
+    required: false
+    default: false
+runs:
+  using: composite
+  steps:
+    - run: |
+        if [ ! -e ${WALDO_CLI_BIN}/waldo ]; then
+            bash -c "$(curl -fLs https://github.com/waldoapp/waldo-go-cli/raw/master/install-waldo.sh)"
+        fi
+
+        build_path=${{ inputs.build_path }}
+        git_branch=${{ inputs.git_branch }}
+        git_commit=${{ inputs.git_commit }}
+        upload_token=${{ inputs.upload_token }}
+        variant_name=${{ inputs.variant_name }}
+        verbose=${{ inputs.is_debug_mode }}
+
+        extra_options=""
+
+        if [[ -n $variant_name ]]; then
+            extra_options="${extra_options} --variant_name \"${variant_name}\""
+        fi
+
+        if [[ -n $git_commit ]]; then
+            extra_options="${extra_options} --git_commit \"${git_commit}\""
+        fi
+
+        if [[ -n $git_branch ]]; then
+            extra_options="${extra_options} --git_branch \"${git_branch}\""
+        fi
+
+        if [[ $verbose == "true" ]]; then
+            extra_options="${extra_options} --verbose"
+        fi
+
+        ${WALDO_CLI_BIN}/waldo upload "$build_path" --upload_token "$upload_token" ${extra_options}
+      env:
+        GITHUB_EVENT_PULL_REQUEST_HEAD_SHA: ${{ github.event.pull_request.head.sha }}
+        WALDO_CLI_BIN: /usr/local/bin
+        WALDO_WRAPPER_NAME_OVERRIDE: 'Custom'
+        WALDO_WRAPPER_VERSION_OVERRIDE: '1.0.0'
+      shell: bash
+branding:
+  icon: upload-cloud
+  color: blue