diff --git a/README.md b/README.md
index 817fa07..5316943 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@ if __name__ == "__main__":
     app.listen(host="127.0.0.1", port=8000)
 ```
 
-Install the canonical SmallOS master dependency, the package, and test tools:
+Install the pinned SmallOS v1.2.0 release, the package, and test tools:
 
 ```console
 python3 -m pip install -r requirements.txt
diff --git a/RELEASING.md b/RELEASING.md
index ed91051..1122b2e 100644
--- a/RELEASING.md
+++ b/RELEASING.md
@@ -45,11 +45,13 @@ python3 -m twine check dist/*
 ## Publishing boundary
 
 The automated process creates a GitHub release; it does not publish to PyPI.
-SmallServer currently installs SmallOS from its canonical Git `master` branch
+SmallServer currently installs the canonical SmallOS `v1.2.0` GitHub release
 through `requirements.txt`, while `pyproject.toml` intentionally has no runtime
 dependency declaration. Publishing the wheel to PyPI before SmallOS has an
-installable release dependency would give users an incomplete installation.
+installable package-index dependency would give users an incomplete
+installation.
 
-Add PyPI trusted publishing only after SmallOS has a stable package release,
-SmallServer declares that dependency in `pyproject.toml`, and an installed-wheel
-test proves a clean environment receives every runtime dependency.
+Add PyPI trusted publishing only after SmallOS has a stable package-index
+release, SmallServer declares that dependency in `pyproject.toml`, and an
+installed-wheel test proves a clean environment receives every runtime
+dependency.
diff --git a/guide/development.md b/guide/development.md
index bb0f035..590651c 100644
--- a/guide/development.md
+++ b/guide/development.md
@@ -2,7 +2,7 @@
 
 ## Set up
 
-Use Python 3.10 or newer and install the canonical SmallOS master checkout plus
+Use Python 3.10 or newer and install the pinned SmallOS v1.2.0 release plus
 SmallServer in editable mode:
 
 ```console
diff --git a/guide/getting-started.md b/guide/getting-started.md
index 1871378..9ff45e0 100644
--- a/guide/getting-started.md
+++ b/guide/getting-started.md
@@ -2,17 +2,18 @@
 
 ## Requirements
 
-SmallServer requires Python 3.10 or newer. During development,
-`requirements.txt` installs SmallOS from the canonical GitHub `master` branch;
-SmallServer itself declares no package-index runtime dependency yet.
+SmallServer requires Python 3.10 or newer. `requirements.txt` installs the
+canonical SmallOS GitHub release tagged `v1.2.0`; SmallServer itself declares
+no package-index runtime dependency yet.
 
 ```console
 python3 -m pip install -r requirements.txt
 python3 -m pip install -e .
 ```
 
-The first command needs Git and network access. Pin the SmallOS revision in
-your own deployment lock or build process if reproducibility matters.
+The first command needs Git and network access. The release tag makes the
+SmallOS source revision reproducible; deployments should still lock all of
+their transitive build dependencies.
 
 ## Create an application
 
diff --git a/guide/platforms-kernels.md b/guide/platforms-kernels.md
index e29f0df..fd0ce11 100644
--- a/guide/platforms-kernels.md
+++ b/guide/platforms-kernels.md
@@ -12,9 +12,10 @@ that runtime, and starts it. If the dependency or Unix kernel is unavailable,
 it raises `ServerConfigurationError` and asks the caller to provide a suitable
 runtime.
 
-The canonical SmallOS dependency is installed from GitHub `master` by
-`requirements.txt`. Python package metadata intentionally has no runtime
-dependency until SmallOS has an unambiguous published distribution contract.
+The canonical SmallOS dependency is installed from the GitHub `v1.2.0` release
+tag by `requirements.txt`. Python package metadata intentionally has no runtime
+dependency until SmallOS has an unambiguous package-index distribution
+contract.
 
 ## Custom and constrained kernels
 
diff --git a/requirements.txt b/requirements.txt
index 9d050d1..cea0232 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,3 @@
-# Install SmallOS directly from its canonical master branch. The PyPI package
-# name is not yet available to this project.
--e git+https://github.com/MikiEEE/SmallOS.git@master#egg=SmallPackage
+# Install the canonical SmallOS v1.2.0 GitHub release. The distribution is not
+# yet consumed from a package index by this project.
+SmallPackage @ git+https://github.com/MikiEEE/SmallOS.git@v1.2.0