diff --git a/.github/workflows/_checks.yml b/.github/workflows/_checks.yml
index 0a03cea..7c11554 100644
--- a/.github/workflows/_checks.yml
+++ b/.github/workflows/_checks.yml
@@ -43,6 +43,36 @@ jobs:
         run: uv run --no-sync python -c "import sys, modern_di_faststream; assert not sys._is_gil_enabled(), 'GIL is enabled on a t-build'"
       - run: just test-ci
 
+  floors:
+    # Every other job resolves newest, so the declared floors are a claim nothing installs.
+    # This one resolves the bottom of each range, on every matrix entry: wheel coverage is
+    # per interpreter, so two interpreters resolving the same versions can still disagree
+    # on whether those versions install.
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version:
+          - "3.10"
+          - "3.11"
+          - "3.12"
+          - "3.13"
+          - "3.14"
+          - "3.14t"
+    steps:
+      - uses: actions/checkout@v6
+      - uses: astral-sh/setup-uv@v8.2.0
+        with:
+          enable-cache: true
+          cache-dependency-glob: "**/pyproject.toml"
+      - run: uv python install ${{ matrix.python-version }}
+      - run: uv python pin ${{ matrix.python-version }}
+      # --no-build so a floor with no wheel for this interpreter fails here instead of
+      # quietly compiling its sdist; --no-install-project because that flag would refuse to
+      # build this project too, and the tests import it from the checkout.
+      - run: uv sync --all-extras --no-install-project --resolution lowest-direct --no-build
+      - run: uv run --no-sync pytest
+
   links:
     runs-on: ubuntu-latest
     steps:
diff --git a/pyproject.toml b/pyproject.toml
index 93da3bb..e9b82d5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,7 +18,14 @@ classifiers = [
     "Typing :: Typed",
     "Topic :: Software Development :: Libraries",
 ]
-dependencies = ["faststream>=0.7,<0.8", "modern-di>=3,<4"]
+dependencies = [
+    "faststream>=0.7,<0.8",
+    # Not imported here: faststream pulls pydantic, and pydantic-core ships no cp313 wheel
+    # before pydantic 2.8.1 and no cp314 wheel before 2.12 - the floor cannot install there.
+    "pydantic>=2.8.1; python_version == '3.13'",
+    "pydantic>=2.12; python_version >= '3.14'",
+    "modern-di>=3,<4",
+]
 version = "0"
 
 [project.urls]
@@ -29,13 +36,14 @@ Issues = "https://github.com/modern-python/modern-di-faststream/issues"
 Changelog = "https://github.com/modern-python/modern-di-faststream/releases"
 
 [dependency-groups]
+# Floored so `uv sync --resolution lowest-direct` resolves a usable harness, not each name's first release.
 dev = [
     "faststream[nats]",
-    "pytest",
-    "pytest-cov",
-    "pytest-asyncio",
-    "httpx",
-    "asgi-lifespan",
+    "pytest>=8",
+    "pytest-cov>=5",
+    "pytest-asyncio>=0.24",
+    "httpx>=0.27",
+    "asgi-lifespan>=2",
 ]
 lint = [
     "ty",