improve build instructions

2 files changed, 3 insertions, 3 deletions

diff --git a/README.md b/README.md
index ca49836..700b0ef 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ The information below is meant to help hack on the codebase. If you're instead l
 
 * Python3 (>= 3.7)
 * [hydrilla.builder](https://git.koszko.org/hydrilla-builder/)
-* flask
+* flask (>= 1.1)
 * click
 * jsonschema (>= 3.0)
 
@@ -50,7 +50,7 @@ sudo apt install python3-flask python3-flask python3-jsonschema \
      python3-setuptools python3-setuptools-scm python3-babel python3-wheel
 ```
 
-If you're using `virtualenv` command to create a virtual environment, make sure you invoke it with `--system-site-packages`. This is necessary for packages installed inside the virtualenv to be able to use globally-installed dependencies.
+If you're using `virtualenv` command to create a virtual environment, make sure you invoke it with `--system-site-packages` and `--no-download`. The first option is necessary for packages installed inside the virtualenv to be able to use globally-installed dependencies. The second one will make `virtualenv` use locally-available base libraries (setuptools, etc.) instead of downloading them from PyPI.
 
 Now, in unpacked source directories of **both** `hydrilla-builder` and `hydrilla`, run the build and installation commands:
 ``` shell
diff --git a/setup.cfg b/setup.cfg
index 8bdce93..5d34285 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -36,7 +36,7 @@ include_package_data=True
 python_requires = >= 3.7
 install_requires =
     hydrilla.builder==1.1b1
-    flask
+    flask>=1.1
     jsonschema>=3.0
 
 [options.package_data]