Question: I'm using pipenv inside a docker container. I tried installing a package and found that the installation succeeds (gets added to the Pipfile), but the locking keeps failing. Everything was fine until yesterday. Here's the error: (app) root@7284b7892266:/usr/src/app# pipenv install scrapy-djangoitem Installing scrapy-djangoitem… Adding scrapy-djangoitem to Pipfile's [packages]… ✔ Installation Succeeded Pipfile.lock (6d808e) out of date, updating to (27ac89)… Locking [dev-packages] dependencies… Building requirements... Resolving dependencies... ✘ Locking Failed! Traceback (most recent call last): File "/usr/local/lib/python3.7/site-packages/pipenv/resolver.py", line 807, in <module> main() File "/usr/local/lib/python3.7/site-packages/pipenv/resolver.py", line 803, in main parsed.requirements_dir, parsed.packages, parse_only=parsed.parse_only) File "/usr/local/lib/python3.7/site-packages/pipenv/resolver.py", line 785, in _main resolve_packages(pre, clear, verbose, system, write, requirements_dir, packages) File "/usr/local/lib/python3.7/site-packages/pipenv/resolver.py", line 758, in resolve_packages results = clean_results(results, resolver, project) File "/usr/local/lib/python3.7/site-packages/pipenv/resolver.py", line 634, in clean_results reverse_deps = project.environment.reverse_dependencies() File "/usr/local/lib/python3.7/site-packages/pipenv/project.py", line 376, in environment self._environment = self.get_environment(allow_global=allow_global) File "/usr/local/lib/python3.7/site-packages/pipenv/project.py", line 366, in get_environment environment.extend_dists(pipenv_dist) File "/usr/local/lib/python3.7/site-packages/pipenv/environment.py", line 127, in extend_dists extras = self.resolve_dist(dist, self.base_working_set) File "/usr/local/lib/python3.7/site-packages/pipenv/environment.py", line 122, in resolve_dist deps |= cls.resolve_dist(dist, working_set) File "/usr/local/lib/python3.7/site-packages/pipenv/environment.py", line 121, in resolve_dist dist = working_set.find(req) File "/root/.local/share/virtualenvs/app-lp47FrbD/lib/python3.7/site-packages/pkg_resources/__init__.py", line 642, in find raise VersionConflict(dist, req) pkg_resources.VersionConflict: (importlib-metadata 2.0.0 (/root/.local/share/virtualenvs/app-lp47FrbD/lib/python3.7/site-packages), Requirement.parse('importlib-metadata<2,>=0.12; python_version < "3.8"')) (app) root@7284b7892266:/usr/src/app#  What could be wrong? EDIT After removing Pipfile.lock and trying to install a package, I got: (app) root@ef80787b5c42:/usr/src/app# pipenv install httpx Installing httpx… Adding httpx to Pipfile's [packages]… ✔ Installation Succeeded Pipfile.lock not found, creating… Locking [dev-packages] dependencies… Building requirements... Resolving dependencies... ✔ Success! Locking [packages] dependencies… Building requirements... ⠏ Locking...Resolving dependencies... Traceback (most recent call last): File "/usr/local/bin/pipenv", line 8, in <module> sys.exit(cli()) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 829, in __call__ return self.main(*args, **kwargs) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 782, in main rv = self.invoke(ctx) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 1259, in invoke return _process_result(sub_ctx.command.invoke(sub_ctx)) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke return ctx.invoke(self.callback, **ctx.params) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/decorators.py", line 73, in new_func return ctx.invoke(f, obj, *args, **kwargs) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/click/decorators.py", line 21, in new_func return f(get_current_context(), *args, **kwargs) File "/usr/local/lib/python3.7/site-packages/pipenv/cli/command.py", line 252, in install site_packages=state.site_packages File "/usr/local/lib/python3.7/site-packages/pipenv/core.py", line 2202, in do_install skip_lock=skip_lock, File "/usr/local/lib/python3.7/site-packages/pipenv/core.py", line 1303, in do_init pypi_mirror=pypi_mirror, File "/usr/local/lib/python3.7/site-packages/pipenv/core.py", line 1113, in do_lock keep_outdated=keep_outdated File "/usr/local/lib/python3.7/site-packages/pipenv/utils.py", line 1323, in venv_resolve_deps c = resolve(cmd, sp) File "/usr/local/lib/python3.7/site-packages/pipenv/utils.py", line 1136, in resolve result = c.expect(u"\n", timeout=environments.PIPENV_INSTALL_TIMEOUT) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/delegator.py", line 215, in expect self.subprocess.expect(pattern=pattern, timeout=timeout) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/pexpect/spawnbase.py", line 344, in expect timeout, searchwindowsize, async_) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/pexpect/spawnbase.py", line 372, in expect_list return exp.expect_loop(timeout) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/pexpect/expect.py", line 181, in expect_loop return self.timeout(e) File "/usr/local/lib/python3.7/site-packages/pipenv/vendor/pexpect/expect.py", line 144, in timeout raise exc pexpect.exceptions.TIMEOUT: <pexpect.popen_spawn.PopenSpawn object at 0x7f81e99bec90> searcher: searcher_re: 0: re.compile('\n') <pexpect.popen_spawn.PopenSpawn object at 0x7f81e99bec90> searcher: searcher_re: 0: re.compile('\n') (app) root@ef80787b5c42:/usr/src/app# 

Answer: Here are my debugging notes. Still not sure which package is causing the problem, but this does seem to fix it. The error you get when you first run pipenv install with pipenv version 2020.8.13. Traceback (most recent call last): File "/usr/local/bin/pipenv", line 8, in <module> sys.exit(cli()) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 829, in __call__ return self.main(*args, **kwargs) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 782, in main rv = self.invoke(ctx) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1259, in invoke return _process_result(sub_ctx.command.invoke(sub_ctx)) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke return ctx.invoke(self.callback, **ctx.params) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/decorators.py", line 73, in new_func return ctx.invoke(f, obj, *args, **kwargs) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 610, in invoke return callback(*args, **kwargs) File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/decorators.py", line 21, in new_func return f(get_current_context(), *args, **kwargs) File "/usr/local/lib/python3.6/site-packages/pipenv/cli/command.py", line 252, in install site_packages=state.site_packages File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 1928, in do_install site_packages=site_packages, File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 580, in ensure_project pypi_mirror=pypi_mirror, File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 512, in ensure_virtualenv python=python, site_packages=site_packages, pypi_mirror=pypi_mirror File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 999, in do_create_virtualenv project._environment.add_dist("pipenv") File "/usr/local/lib/python3.6/site-packages/pipenv/environment.py", line 135, in add_dist self.extend_dists(dist) File "/usr/local/lib/python3.6/site-packages/pipenv/environment.py", line 127, in extend_dists extras = self.resolve_dist(dist, self.base_working_set) File "/usr/local/lib/python3.6/site-packages/pipenv/environment.py", line 122, in resolve_dist deps |= cls.resolve_dist(dist, working_set) File "/usr/local/lib/python3.6/site-packages/pipenv/environment.py", line 121, in resolve_dist dist = working_set.find(req) File "/usr/local/lib/python3.6/site-packages/pkg_resources/__init__.py", line 642, in find raise VersionConflict(dist, req) pkg_resources.VersionConflict: (importlib-metadata 2.0.0 (/usr/local/lib/python3.6/site-packages), Requirement.parse('importlib-metadata<2,>=0.12; python_version < "3.8"'))  If you run pip install -U pipenv it seems to change the importlib-metadata version: Installing collected packages: importlib-metadata Attempting uninstall: importlib-metadata Found existing installation: importlib-metadata 2.0.0 Uninstalling importlib-metadata-2.0.0: Successfully uninstalled importlib-metadata-2.0.0 Successfully installed importlib-metadata-1.7.0  Now if you run pipenv install -d --skip-lock it will finish. It seems like a library is requiring a version >= importlib-metadata 2.0. When I pinned the following dependencies it didn't work at first when running pipenv lock, however, if I removed the lock file (rm Pipenv.lock) then it worked when I ran pipenv lock again. virtualenv = "==20.0.31" importlib-metadata = "==1.7.0"