diff --git a/changelog.md b/changelog.md
index f595e672..0f8b575e 100644
--- a/changelog.md
+++ b/changelog.md
@@ -30,6 +30,7 @@ Internal
 * Sync prompt format string commentary with web.
 * Add a GitHub Actions workflow to run Codex review on pull requests.
 * Remove vim-style exit sequence which had no effect.
+* Pin dependencies more tightly in `pyproject.toml`.
 
 
 1.53.0 (2026/02/12)
diff --git a/pyproject.toml b/pyproject.toml
index 40804643..82255536 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -9,18 +9,18 @@ authors = [{ name = "Mycli Core Team", email = "mycli-dev@googlegroups.com" }]
 urls = { homepage = "http://mycli.net" }
 
 dependencies = [
-    "click >= 8.3.1",
-    "cryptography >= 1.0.0",
+    "click ~= 8.3.1",
+    "cryptography ~= 46.0.5",
     "Pygments ~= 2.19.2",
     "prompt_toolkit>=3.0.6,<4.0.0",
-    "PyMySQL >= 0.9.2",
+    "PyMySQL ~= 1.1.2",
     "sqlparse>=0.3.0,<0.6.0",
     "sqlglot[rs] == 27.*",
-    "configobj >= 5.0.5",
-    "cli_helpers[styles] >= 2.10.0",
-    "pyperclip >= 1.8.1",
-    "pycryptodomex",
-    "pyfzf >= 0.3.1",
+    "configobj ~= 5.0.9",
+    "cli_helpers[styles] ~= 2.10.0",
+    "pyperclip ~= 1.11.0",
+    "pycryptodomex ~= 3.23.0",
+    "pyfzf ~= 0.3.1",
     "rapidfuzz ~= 3.14.3",
     "keyring ~= 25.7.0",
 ]
@@ -34,33 +34,33 @@ build-backend = "setuptools.build_meta"
 
 [project.optional-dependencies]
 ssh = [
-    "paramiko~=3.5.1",
-    "sshtunnel",
+    "paramiko ~= 3.5.1",
+    "sshtunnel ~= 0.4.0",
 ]
 llm = [
-    "llm>=0.19.0",
-    "setuptools",                   # Required by llm commands to install models
-    "pip",
+    "llm ~= 0.28.0",
+    "setuptools == 82.*",                   # Required by llm commands to install models
+    "pip == 26.*",
 ]
 all = [
   "mycli[ssh]",
   "mycli[llm]",
 ]
 dev = [
-    "behave>=1.2.6",
-    "coverage>=7.2.7",
-    "mypy~=1.18.1",
-    "pexpect>=4.9.0",
-    "pytest>=7.4.4",
-    "pytest-cov>=4.1.0",
-    "tox>=4.8.0",
-    "pdbpp>=0.10.3",
-    "paramiko~=3.5.1",
-    "sshtunnel",
-    "llm>=0.19.0",
-    "setuptools",                   # Required by llm commands to install models
-    "pip",
-    "ruff~=0.15.0",
+    "behave ~= 1.3.3",
+    "coverage ~= 7.13.4",
+    "mypy ~= 1.19.1",
+    "pexpect ~= 4.9.0",
+    "pytest ~= 9.0.2",
+    "pytest-cov ~= 7.0.0",
+    "tox ~= 4.35.0",
+    "pdbpp ~= 0.11.7",
+    "paramiko ~= 3.5.1",
+    "sshtunnel ~= 0.4.0",
+    "llm ~= 0.28.0",
+    "setuptools == 82.*",                   # Required by llm commands to install models
+    "pip == 26.*",
+    "ruff ~= 0.15.0",
 ]
 
 [project.scripts]