diff --git a/.tests/all_pytests.sh b/.tests/all_pytests.sh
index f975a77..913f95b 100755
--- a/.tests/all_pytests.sh
+++ b/.tests/all_pytests.sh
@@ -8,20 +8,9 @@ all_application_folders=(
   "hello-tasks"
 )
 
-# In case of any errors, this test has failed. Fail immediately.
-set -e
-# In case of undefined variables, there must be a bug. Fail immediately.
-set -u
-# Show us the commands we're executing, to aid in debugging.
-set -x
-
-# Check that this script has been invoked with the right working directory, by
-# checking that the expected subdirectories exist.
-ls -l api/ hello-constructors/backend/src/ 2> /dev/null > /dev/null || {
-  echo "ERROR: this script must be invoked from the root of the 'reboot-examples' repository."
-  echo "Current working directory is '$(pwd)'."
-  exit 1
-}
+set -e # Exit if a command exits with an error.
+set -u # In case of undefined variables, there must be a bug. Fail immediately.
+set -x # Echo executed commands to help debug failures.
 
 # Require `REBOOT_WHL_FILE` to have been passed; all tests calling this
 # file should be explicit about a specific Reboot wheel file they've built.
@@ -45,18 +34,11 @@ function runPyTest () {
   popd
 }
 
-# Convert symlinks to files that we need to mutate into copies.
-for file in "requirements.lock" "requirements-dev.lock" "pyproject.toml"; do
-  cp "$file" "${file}.tmp"
-  rm "$file"
-  mv "${file}.tmp" "$file"
-done
-
 # Install the `reboot` package from the specified path explicitly, over-
 # writing the version from `pyproject.toml`.
 rye remove --no-sync reboot
 rye remove --no-sync --dev reboot
-rye add --dev reboot --absolute --path=$REBOOT_WHL_FILE
+rye add --dev reboot --absolute --path=${SANDBOX_ROOT}$REBOOT_WHL_FILE
 
 # Create and activate a virtual environment.
 rye sync --no-lock
diff --git a/.tests/readme_test.sh b/.tests/readme_test.sh
index 88b426c..f856f56 100755
--- a/.tests/readme_test.sh
+++ b/.tests/readme_test.sh
@@ -1,29 +1,11 @@
 #!/bin/bash
 #
-# This test mirrors, as closely as possible, the user experience of following
-# the `README.md` through its "Test" step.
+# This test should fully cover the user experience of following
+# the `README.md` through its "Test" step. Because it is not
+# interactive, it cannot perfectly match the README.md.
 
-### Preamble: sanity checks and setup not found in the `README.md`. ###
-
-# In case of any errors, this test has failed. Fail immediately.
-set -e
-# Show us the commands we're executing, to aid in debugging.
-set -x
-
-# Check that this script has been invoked with the right working directory, by
-# checking that the expected subdirectories exist.
-ls -l api/ hello-constructors/backend/src/ 2> /dev/null > /dev/null || {
-  echo "ERROR: this script must be invoked from the root of the 'reboot-examples' repository."
-  echo "Current working directory is '$(pwd)'."
-  exit 1
-}
-
-# Convert symlinks to files that we need to mutate into copies.
-for file in "requirements.lock" "requirements-dev.lock" "pyproject.toml"; do
-  cp "$file" "${file}.tmp"
-  rm "$file"
-  mv "${file}.tmp" "$file"
-done
+set -e # Exit if a command exits with an error.
+set -x # Echo executed commands to help debug failures.
 
 # Use the published Reboot pip package by default, but allow the test system
 # to override them with a different value.
@@ -32,24 +14,22 @@ if [ -n "$REBOOT_WHL_FILE" ]; then
   # writing the version from `pyproject.toml`.
   rye remove --no-sync reboot
   rye remove --no-sync --dev reboot
-  rye add --dev reboot --absolute --path=$REBOOT_WHL_FILE
+  rye add --dev reboot --absolute --path=${SANDBOX_ROOT}$REBOOT_WHL_FILE
 fi
 
-### Start of the README.md test ###
-# From here on we follow the `README.md` instructions verbatim.
-
 # Create and activate a virtual environment.
 rye sync --no-lock
 source .venv/bin/activate
 
 cd hello-constructors
 
-# Compile protocol buffers.
-rbt protoc
+# When running in a Bazel test, our `.rbtrc` file ends up in a very deep
+# directory structure, which can result in "path too long" errors from RocksDB.
+# Explicitly specify a shorter path.
+RBT_FLAGS="--state-directory=$(mktemp -d)"
+
+# Confirm that we can start up.
+rbt $RBT_FLAGS dev run --terminate-after-health-check
 
 # Test.
 pytest backend/
-
-# Deactivate the virtual environment, since we can run a test which may require
-# another virtual environment (currently we do that only in `all_tests.sh`).
-deactivate
diff --git a/README.md b/README.md
index c83152d..8ce9ed0 100644
--- a/README.md
+++ b/README.md
@@ -76,7 +76,7 @@ way of keeping the options you have to type (and remember!) to a minimum. We
 provide a different `.rbtrc` for every application in this repository, and by
 selecting an application directory you select the `.rbtrc` that will be used:
 
-<!-- MARKDOWN-AUTO-DOCS:START (CODE:src=./.tests/readme_test.sh&lines=45-45) -->
+<!-- MARKDOWN-AUTO-DOCS:START (CODE:src=./.tests/readme_test.sh&lines=24-24) -->
 <!-- The below code snippet is automatically added from ./.tests/readme_test.sh -->
 ```sh
 cd hello-constructors
diff --git a/bank/cli.py b/bank/cli.py
index 81b596f..9ebaf78 100755
--- a/bank/cli.py
+++ b/bank/cli.py
@@ -17,9 +17,9 @@
 def configure_parser() -> argparse.ArgumentParser:
     parser = argparse.ArgumentParser()
     parser.add_argument(
-        "--gateway_address",
+        "--application_api_url",
         type=str,
-        default="localhost:9991",
+        default="http://localhost:9991",
     )
     parser.add_argument(
         "--bank_id",
@@ -91,10 +91,10 @@ def configure_parser() -> argparse.ArgumentParser:
     return parser
 
 
-async def run_action(args: argparse.Namespace) -> int:
+async def run_action(args: argparse.Namespace) -> None:
     context = ExternalContext(
         name=f"bank-cli-action-{str(uuid.uuid4())}",
-        gateway=args.gateway_address,
+        url=args.application_api_url,
     )
 
     bank = Bank.lookup(args.bank_id)
diff --git a/hello-constructors/backend/src/main.py b/hello-constructors/backend/src/main.py
index dd4c86c..14c339c 100644
--- a/hello-constructors/backend/src/main.py
+++ b/hello-constructors/backend/src/main.py
@@ -12,8 +12,9 @@
 
 async def initialize(context: ExternalContext):
     # Explicitly create the state machine.
-    hello, _ = await Hello.construct().idempotently().Create(
-        EXAMPLE_STATE_MACHINE_ID,
+    hello, _ = await Hello.construct(
+        id=EXAMPLE_STATE_MACHINE_ID
+    ).idempotently().Create(
         context,
         initial_message="Welcome! This message was sent by a constructor.",
     )
diff --git a/pyproject.toml b/pyproject.toml
index a8264ca..b8f681a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [project]
 requires-python = ">= 3.10"
 dependencies = [
-    "reboot==0.19.2",
+    "reboot==0.20.0",
 ]
 
 [tool.rye]
@@ -9,7 +9,7 @@ dev-dependencies = [
     "mypy==1.2.0",
     "pytest>=7.4.2",
     "types-protobuf>=4.24.0.20240129",
-    "reboot==0.19.2",
+    "reboot==0.20.0",
 ]
 
 # This project only uses `rye` to provide `python` and its dependencies, so
diff --git a/requirements-dev.lock b/requirements-dev.lock
index 410c374..7e6696b 100644
--- a/requirements-dev.lock
+++ b/requirements-dev.lock
@@ -139,7 +139,7 @@ python-dateutil==2.9.0.post0
 pyyaml==6.0.2
     # via kubernetes-asyncio
     # via reboot
-reboot==0.19.2
+reboot==0.20.0
 setuptools==75.1.0
     # via grpcio-tools
 six==1.16.0
diff --git a/requirements.lock b/requirements.lock
index 303443b..a4ec78b 100644
--- a/requirements.lock
+++ b/requirements.lock
@@ -128,7 +128,7 @@ python-dateutil==2.9.0.post0
 pyyaml==6.0.2
     # via kubernetes-asyncio
     # via reboot
-reboot==0.19.2
+reboot==0.20.0
 setuptools==75.1.0
     # via grpcio-tools
 six==1.16.0