docs: fix dependencies section in readme

Problem: time and timeout were listed as optional dependencies despite
being required for plugin initialization. nix was not mentioned as an
alternative to uv for the Python scraping environment.

Solution: rename section to "Dependencies", list time/timeout first,
and add nix as an alternative to uv for scraping.

.envrc

@@ -1,3 +0,0 @@
-VIRTUAL_ENV="$PWD/.venv"
-PATH_add "$VIRTUAL_ENV/bin"
-export VIRTUAL_ENV

.github/workflows/ci.yaml

@@ -1,112 +0,0 @@
-name: ci
-on:
-  workflow_call:
-  pull_request:
-    branches: [main]
-  push:
-    branches: [main]
-
-jobs:
-  changes:
-    runs-on: ubuntu-latest
-    outputs:
-      lua: ${{ steps.changes.outputs.lua }}
-      python: ${{ steps.changes.outputs.python }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: dorny/paths-filter@v3
-        id: changes
-        with:
-          filters: |
-            lua:
-              - 'lua/**'
-              - 'spec/**'
-              - 'plugin/**'
-              - 'after/**'
-              - 'ftdetect/**'
-              - '*.lua'
-              - '.luarc.json'
-              - 'stylua.toml'
-              - 'selene.toml'
-            python:
-              - 'scripts/**'
-              - 'scrapers/**'
-              - 'tests/**'
-              - 'pyproject.toml'
-              - 'uv.lock'
-
-  lua-format:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.lua == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: JohnnyMorganz/stylua-action@v4
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          version: 2.1.0
-          args: --check .
-
-  lua-lint:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.lua == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: NTBBloodbath/selene-action@v1.0.0
-        with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          args: --display-style quiet .
-
-  lua-typecheck:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.lua == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: mrcjkb/lua-typecheck-action@v0
-        with:
-          checklevel: Warning
-          directories: lua
-          configpath: .luarc.json
-
-  python-format:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.python == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v4
-      - run: uv tool install ruff
-      - run: ruff format --check .
-
-  python-lint:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.python == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v4
-      - run: uv tool install ruff
-      - run: ruff check .
-
-  python-typecheck:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.python == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v4
-      - run: uv sync --dev
-      - run: uvx ty check .
-
-  python-test:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.python == 'true' }}
-    steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v4
-      - run: uv sync --dev
-      - run: uv run camoufox fetch
-      - run: uv run pytest tests/ -v

.github/workflows/test.yaml

@@ -44,9 +44,7 @@ jobs:
       - uses: actions/checkout@v4
       - name: Install uv
         uses: astral-sh/setup-uv@v4
-      - name: Install dependencies with pytest
+      - name: Install dependencies
         run: uv sync --dev
-      - name: Fetch camoufox data
-        run: uv run camoufox fetch
       - name: Run Python tests
         run: uv run pytest tests/ -v

.gitignore

@@ -14,3 +14,6 @@ __pycache__
 .claude/
 
 node_modules/
+
+.envrc
+.direnv/

README.md

@@ -28,11 +28,12 @@ Install using your package manager of choice or via
 luarocks install cp.nvim
 ```
 
-## Optional Dependencies
+## Dependencies
 
-- [uv](https://docs.astral.sh/uv/) for problem scraping
 - GNU [time](https://www.gnu.org/software/time/) and
   [timeout](https://www.gnu.org/software/coreutils/manual/html_node/timeout-invocation.html)
+- [uv](https://docs.astral.sh/uv/) or [nix](https://nixos.org/) for problem
+  scraping
 
 ## Quick Start
 

doc/cp.nvim.txt

@@ -19,188 +19,13 @@ REQUIREMENTS                                                 *cp-requirements*
 - uv package manager (https://docs.astral.sh/uv/)
 
 ==============================================================================
-COMMANDS                                                         *cp-commands*
+SETUP                                                              *cp-setup*
 
-:CP                                                                      *:CP*
-        cp.nvim uses a single :CP command with intelligent argument parsing:
-
-        Setup Commands ~
-            :CP {platform} {contest_id} [--lang {language}]
-                                Full setup: set platform and load contest metadata.
-                                Scrapes test cases and creates source file.
-                                --lang: Use specific language (default: platform default)
-                                Examples: >
-                                    :CP codeforces 1933
-                                    :CP codeforces 1933 --lang python
-<
-        View Commands ~
-            :CP run [all|n|n,m,...] [--debug]
-                                Run tests in I/O view (see |cp-io-view|).
-                                Lightweight split showing test verdicts.
-
-                                Execution modes:
-                                • :CP run              Combined: single execution with all tests
-                                                       (auto-switches to individual when multiple samples)
-                                • :CP run all          Individual: N separate executions
-                                • :CP run n            Individual: run test n only
-                                • :CP run n,m,...      Individual: run specific tests (e.g. nth and mth)
-
-                                --debug: Use debug build (builds to build/<name>.dbg)
-
-                                Combined mode runs all test inputs in one execution (matching
-                                platform behavior for multi-test problems). When a problem has
-                                multiple independent sample test cases, :CP run auto-switches to
-                                individual mode to run each sample separately.
-
-                                Examples: >
-                                    :CP run              " Combined: all tests, one execution
-                                    :CP run all          " Individual: all tests, N executions
-                                    :CP run 2            " Individual: test 2 only
-                                    :CP run 1,3,5        " Individual: tests 1, 3, and 5
-                                    :CP run all --debug  " Individual with debug build
-<
-            :CP panel [--debug] [n]
-                                Open full-screen test panel (see |cp-panel|).
-                                Aggregate table with diff modes for detailed analysis.
-                                Optional [n] focuses on specific test.
-                                --debug: Use debug build (with sanitizers, etc.)
-                                Examples: >
-                                    :CP panel            " All tests
-                                    :CP panel --debug 3  " Test 3, debug build
-<
-
-            :CP pick [--lang {language}]
-                                Launch configured picker for interactive
-                                platform/contest selection.
-                                --lang: Pre-select language for chosen contest.
-                                Example: >
-                                    :CP pick
-                                    :CP pick --lang python
-<
-
-            :CP interact [script]
-                                Open an interactive terminal for the current problem.
-                                If an executable interactor is provided, runs the compiled
-                                binary against the source file (see
-                                *cp-interact*). Otherwise, runs the source
-                                file. Only valid for interactive problems.
-
-        Navigation Commands ~
-            :CP next [--lang {language}]
-                                Navigate to next problem in current contest.
-                                Stops at last problem (no wrapping).
-                                --lang: Use specific language for next problem.
-                                By default, preserves current file's language if
-                                enabled for the new problem, otherwise uses platform
-                                default.
-                                Examples: >
-                                    :CP next
-                                    :CP next --lang python
-<
-            :CP prev [--lang {language}]
-                                Navigate to previous problem in current contest.
-                                Stops at first problem (no wrapping).
-                                --lang: Use specific language for previous problem.
-                                By default, preserves current file's language if
-                                enabled for the new problem, otherwise uses platform
-                                default.
-                                Examples: >
-                                    :CP prev
-                                    :CP prev --lang cpp
-<
-            :CP {problem_id} [--lang {language}]
-                                Jump to problem {problem_id} in a contest.
-                                Requires that a contest has already been set up.
-                                --lang: Use specific language for this problem.
-                                Examples: >
-                                    :CP B
-                                    :CP C --lang python
-<
-
-        Edit Commands ~
-            :CP edit [n]
-                                Open grid test editor showing all test cases.
-                                Tests displayed as 2×N grid (2 rows, N columns):
-                                • Top row: Test inputs (editable)
-                                • Bottom row: Expected outputs (editable)
-
-                                Optional [n]: Jump cursor to test n's input buffer
-
-                                Changes saved to both cache and disk on exit,
-                                taking effect immediately in :CP run and CLI.
-
-                                Keybindings (configurable via |EditConfig|):
-                                  q         Save all and exit editor
-                                  ]t        Jump to next test column
-                                  [t        Jump to previous test column
-                                  gd        Delete current test column
-                                  ga        Add new test column at end
-                                  <c-w>     Normal window navigation
-
-                                Examples: >
-                                    :CP edit        " Edit all tests
-                                    :CP edit 3      " Edit all, start at test 3
-<
-
-        State Restoration ~
-            :CP                 Restore state from current file.
-                                Automatically detects platform, contest, problem,
-                                and language from cached state. Use this after
-                                switching files to restore your CP environment.
-
-        Cache Commands ~
-            :CP cache clear [platform] [contest]
-                                Clear cache data at different granularities:
-                                • No args: Clear all cached data
-                                • [platform]: Clear all data for a platform
-                                • [platform] [contest]: Clear specific contest
-                                Examples: >
-                                    :CP cache clear
-                                    :CP cache clear codeforces
-                                    :CP cache clear codeforces 1848
-<
-            :CP cache read
-                                View the cache in a pretty-printed lua buffer.
-                                Exit with q.
-
-Template Variables ~
-                                                            *cp-template-vars*
-    Command templates support variable substitution using {variable} syntax:
-
-    • {source}      Source file path (e.g. "abc324a.cpp")
-    • {binary}      Output binary path (e.g. "build/abc324a.run" or
-                    "build/abc324a.dbg" for debug builds)
-
-    Example template: >
-        build = { 'g++', '{source}', '-o', '{binary}', '-std=c++17' }
-<    Would expand to: >
-        g++ abc324a.cpp -o build/abc324a.run -std=c++17
-<
-Debug Builds ~
-                                                            *cp-debug-builds*
-    The --debug flag uses the debug command configuration instead of build:
-
-    • Normal build:  commands.build → outputs to build/<name>.run
-    • Debug build:   commands.debug → outputs to build/<name>.dbg
-
-    Debug builds typically include sanitizers (address, undefined behavior) to
-    catch memory errors, buffer overflows, and other issues. Both binaries
-    coexist, so you can switch between normal and debug mode without
-    recompiling.
-
-    Example debug configuration: >
-        languages = {
-          cpp = {
-            extension = 'cc',
-            commands = {
-              build = { 'g++', '-std=c++17', '{source}', '-o', '{binary}' },
-              run   = { '{binary}' },
-              debug = { 'g++', '-std=c++17', '-fsanitize=address,undefined',
-                        '{source}', '-o', '{binary}' },
-            }
-          }
-        }
+Load cp.nvim with your package manager. For example, with lazy.nvim: >lua
+    { 'barrettruth/cp.nvim' }
 <
+The plugin works automatically with no configuration required. For
+customization, see |cp-config|.
 
 ==============================================================================
 CONFIGURATION                                                      *cp-config*
@@ -425,12 +250,232 @@ run CSES problems with Rust using the single schema:
             print("Source file: " .. state.get_source_file())
           end,
           setup_io_input = function(bufnr, state)
-            -- Custom setup for input buffer
             vim.api.nvim_set_option_value('number', false, { buf = bufnr })
           end
         }
 <
 
+==============================================================================
+COMMANDS                                                         *cp-commands*
+
+:CP                                                                      *:CP*
+        cp.nvim uses a single :CP command with intelligent argument parsing:
+
+        Setup Commands ~
+            :CP {platform} {contest_id} [--lang {language}]
+                                Full setup: set platform and load contest metadata.
+                                Scrapes test cases and creates source file.
+                                --lang: Use specific language (default: platform default)
+                                Examples: >
+                                    :CP codeforces 1933
+                                    :CP codeforces 1933 --lang python
+<
+        View Commands ~
+            :CP run [all|n|n,m,...] [--debug]
+                                Run tests in I/O view (see |cp-io-view|).
+                                Lightweight split showing test verdicts.
+
+                                Execution modes:
+                                • :CP run              Combined: single execution with all tests
+                                                       (auto-switches to individual when multiple samples)
+                                • :CP run all          Individual: N separate executions
+                                • :CP run n            Individual: run test n only
+                                • :CP run n,m,...      Individual: run specific tests (e.g. nth and mth)
+
+                                --debug: Use debug build (builds to build/<name>.dbg)
+
+                                Combined mode runs all test inputs in one execution (matching
+                                platform behavior for multi-test problems). When a problem has
+                                multiple independent sample test cases, :CP run auto-switches to
+                                individual mode to run each sample separately.
+
+                                Examples: >
+                                    :CP run              " Combined: all tests, one execution
+                                    :CP run all          " Individual: all tests, N executions
+                                    :CP run 2            " Individual: test 2 only
+                                    :CP run 1,3,5        " Individual: tests 1, 3, and 5
+                                    :CP run all --debug  " Individual with debug build
+<
+            :CP panel [--debug] [n]
+                                Open full-screen test panel (see |cp-panel|).
+                                Aggregate table with diff modes for detailed analysis.
+                                Optional [n] focuses on specific test.
+                                --debug: Use debug build (with sanitizers, etc.)
+                                Examples: >
+                                    :CP panel            " All tests
+                                    :CP panel --debug 3  " Test 3, debug build
+<
+
+            :CP pick [--lang {language}]
+                                Launch configured picker for interactive
+                                platform/contest selection.
+                                --lang: Pre-select language for chosen contest.
+                                Example: >
+                                    :CP pick
+                                    :CP pick --lang python
+<
+
+            :CP interact [script]
+                                Open an interactive terminal for the current problem.
+                                If an executable interactor is provided, runs the compiled
+                                binary against the source file (see
+                                *cp-interact*). Otherwise, runs the source
+                                file. Only valid for interactive problems.
+
+        Navigation Commands ~
+            :CP next [--lang {language}]
+                                Navigate to next problem in current contest.
+                                Stops at last problem (no wrapping).
+                                --lang: Use specific language for next problem.
+                                By default, preserves current file's language if
+                                enabled for the new problem, otherwise uses platform
+                                default.
+                                Examples: >
+                                    :CP next
+                                    :CP next --lang python
+<
+            :CP prev [--lang {language}]
+                                Navigate to previous problem in current contest.
+                                Stops at first problem (no wrapping).
+                                --lang: Use specific language for previous problem.
+                                By default, preserves current file's language if
+                                enabled for the new problem, otherwise uses platform
+                                default.
+                                Examples: >
+                                    :CP prev
+                                    :CP prev --lang cpp
+<
+            :CP {problem_id} [--lang {language}]
+                                Jump to problem {problem_id} in a contest.
+                                Requires that a contest has already been set up.
+                                --lang: Use specific language for this problem.
+                                Examples: >
+                                    :CP B
+                                    :CP C --lang python
+<
+
+        Edit Commands ~
+            :CP edit [n]
+                                Open grid test editor showing all test cases.
+                                Tests displayed as 2×N grid (2 rows, N columns):
+                                • Top row: Test inputs (editable)
+                                • Bottom row: Expected outputs (editable)
+
+                                Optional [n]: Jump cursor to test n's input buffer
+
+                                Changes saved to both cache and disk on exit,
+                                taking effect immediately in :CP run and CLI.
+
+                                Keybindings (configurable via |EditConfig|):
+                                  q         Save all and exit editor
+                                  ]t        Jump to next test column
+                                  [t        Jump to previous test column
+                                  gd        Delete current test column
+                                  ga        Add new test column at end
+                                  <c-w>     Normal window navigation
+
+                                Examples: >
+                                    :CP edit        " Edit all tests
+                                    :CP edit 3      " Edit all, start at test 3
+<
+
+        State Restoration ~
+            :CP                 Restore state from current file.
+                                Automatically detects platform, contest, problem,
+                                and language from cached state. Use this after
+                                switching files to restore your CP environment.
+
+        Cache Commands ~
+            :CP cache clear [platform] [contest]
+                                Clear cache data at different granularities:
+                                • No args: Clear all cached data
+                                • [platform]: Clear all data for a platform
+                                • [platform] [contest]: Clear specific contest
+                                Examples: >
+                                    :CP cache clear
+                                    :CP cache clear codeforces
+                                    :CP cache clear codeforces 1848
+<
+            :CP cache read
+                                View the cache in a pretty-printed lua buffer.
+                                Exit with q.
+
+Template Variables ~
+                                                            *cp-template-vars*
+    Command templates support variable substitution using {variable} syntax:
+
+    • {source}      Source file path (e.g. "abc324a.cpp")
+    • {binary}      Output binary path (e.g. "build/abc324a.run" or
+                    "build/abc324a.dbg" for debug builds)
+
+    Example template: >
+        build = { 'g++', '{source}', '-o', '{binary}', '-std=c++17' }
+<    Would expand to: >
+        g++ abc324a.cpp -o build/abc324a.run -std=c++17
+<
+Debug Builds ~
+                                                            *cp-debug-builds*
+    The --debug flag uses the debug command configuration instead of build:
+
+    • Normal build:  commands.build → outputs to build/<name>.run
+    • Debug build:   commands.debug → outputs to build/<name>.dbg
+
+    Debug builds typically include sanitizers (address, undefined behavior) to
+    catch memory errors, buffer overflows, and other issues. Both binaries
+    coexist, so you can switch between normal and debug mode without
+    recompiling.
+
+    Example debug configuration: >
+        languages = {
+          cpp = {
+            extension = 'cc',
+            commands = {
+              build = { 'g++', '-std=c++17', '{source}', '-o', '{binary}' },
+              run   = { '{binary}' },
+              debug = { 'g++', '-std=c++17', '-fsanitize=address,undefined',
+                        '{source}', '-o', '{binary}' },
+            }
+          }
+        }
+<
+
+==============================================================================
+MAPPINGS                                                        *cp-mappings*
+
+cp.nvim provides <Plug> mappings for all primary actions. These dispatch
+through the same code path as |:CP|.
+
+                                                              *<Plug>(cp-run)*
+<Plug>(cp-run)          Run tests in I/O view. Equivalent to :CP run.
+
+                                                            *<Plug>(cp-panel)*
+<Plug>(cp-panel)        Open full-screen test panel. Equivalent to :CP panel.
+
+                                                             *<Plug>(cp-edit)*
+<Plug>(cp-edit)         Open the test case editor. Equivalent to :CP edit.
+
+                                                             *<Plug>(cp-next)*
+<Plug>(cp-next)         Navigate to the next problem. Equivalent to :CP next.
+
+                                                             *<Plug>(cp-prev)*
+<Plug>(cp-prev)         Navigate to the previous problem. Equivalent to :CP prev.
+
+                                                             *<Plug>(cp-pick)*
+<Plug>(cp-pick)         Launch the contest picker. Equivalent to :CP pick.
+
+                                                         *<Plug>(cp-interact)*
+<Plug>(cp-interact)     Open interactive mode. Equivalent to :CP interact.
+
+Example configuration: >lua
+    vim.keymap.set('n', '<leader>cr', '<Plug>(cp-run)')
+    vim.keymap.set('n', '<leader>cp', '<Plug>(cp-panel)')
+    vim.keymap.set('n', '<leader>ce', '<Plug>(cp-edit)')
+    vim.keymap.set('n', '<leader>cn', '<Plug>(cp-next)')
+    vim.keymap.set('n', '<leader>cN', '<Plug>(cp-prev)')
+    vim.keymap.set('n', '<leader>cc', '<Plug>(cp-pick)')
+    vim.keymap.set('n', '<leader>ci', '<Plug>(cp-interact)')
+<
+
 ==============================================================================
 LANGUAGE SELECTION                                           *cp-lang-selection*
 

flake.lock

@@ -0,0 +1,43 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1771008912,
+        "narHash": "sha256-gf2AmWVTs8lEq7z/3ZAsgnZDhWIckkb+ZnAo5RzSxJg=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "a82ccc39b39b621151d6732718e3e250109076fa",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "systems": "systems"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1689347949,
+        "narHash": "sha256-12tWmuL2zgBgZkdoB6qXZsgJEH9LR3oUgpaQq2RbI80=",
+        "owner": "nix-systems",
+        "repo": "default-linux",
+        "rev": "31732fcf5e8fea42e59c2488ad31a0e651500f68",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default-linux",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,72 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    systems.url = "github:nix-systems/default-linux";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      systems,
+    }:
+    let
+      eachSystem = nixpkgs.lib.genAttrs (import systems);
+      pkgsFor = system: nixpkgs.legacyPackages.${system};
+
+      mkPythonEnv =
+        pkgs:
+        pkgs.python312.withPackages (ps: [
+          ps.backoff
+          ps.beautifulsoup4
+          ps.curl-cffi
+          ps.httpx
+          ps.ndjson
+          ps.pydantic
+          ps.requests
+        ]);
+
+      mkPlugin =
+        pkgs:
+        let
+          pythonEnv = mkPythonEnv pkgs;
+        in
+        pkgs.vimUtils.buildVimPlugin {
+          pname = "cp-nvim";
+          version = "0-unstable-${self.shortRev or self.dirtyShortRev or "dev"}";
+          src = self;
+          postPatch = ''
+            substituteInPlace lua/cp/utils.lua \
+              --replace-fail "local _nix_python = nil" \
+              "local _nix_python = '${pythonEnv.interpreter}'"
+          '';
+          nvimSkipModule = [
+            "cp.pickers.telescope"
+            "cp.version"
+          ];
+          passthru = { inherit pythonEnv; };
+          meta.description = "Competitive programming plugin for Neovim";
+        };
+    in
+    {
+      overlays.default = final: prev: {
+        vimPlugins = prev.vimPlugins // {
+          cp-nvim = mkPlugin final;
+        };
+      };
+
+      packages = eachSystem (system: {
+        default = mkPlugin (pkgsFor system);
+        pythonEnv = mkPythonEnv (pkgsFor system);
+      });
+
+      devShells = eachSystem (system: {
+        default = (pkgsFor system).mkShell {
+          packages = with (pkgsFor system); [
+            uv
+            python312
+          ];
+        };
+      });
+    };
+}

lua/cp/config.lua

@@ -292,7 +292,15 @@ end
 ---@return cp.Config
 function M.setup(user_config)
   vim.validate({ user_config = { user_config, { 'table', 'nil' }, true } })
-  local cfg = vim.tbl_deep_extend('force', vim.deepcopy(M.defaults), user_config or {})
+  local defaults = vim.deepcopy(M.defaults)
+  if user_config and user_config.platforms then
+    for plat in pairs(defaults.platforms) do
+      if not user_config.platforms[plat] then
+        defaults.platforms[plat] = nil
+      end
+    end
+  end
+  local cfg = vim.tbl_deep_extend('force', defaults, user_config or {})
 
   if not next(cfg.languages) then
     error('[cp.nvim] At least one language must be configured')

lua/cp/health.lua

@@ -5,6 +5,8 @@ local utils = require('cp.utils')
 local function check()
   vim.health.start('cp.nvim [required] ~')
 
+  utils.setup_python_env()
+
   if vim.fn.has('nvim-0.10.0') == 1 then
     vim.health.ok('Neovim 0.10.0+ detected')
   else
@@ -16,22 +18,37 @@ local function check()
     vim.health.error('Windows is not supported')
   end
 
-  if vim.fn.executable('uv') == 1 then
-    vim.health.ok('uv executable found')
-    local r = vim.system({ 'uv', '--version' }, { text = true }):wait()
+  if utils.is_nix_build() then
+    local source = utils.is_nix_discovered() and 'runtime discovery' or 'flake install'
+    vim.health.ok('Nix Python environment detected (' .. source .. ')')
+    local py = utils.get_nix_python()
+    vim.health.info('Python: ' .. py)
+    local r = vim.system({ py, '--version' }, { text = true }):wait()
     if r.code == 0 then
-      vim.health.info('uv version: ' .. r.stdout:gsub('\n', ''))
+      vim.health.info('Python version: ' .. r.stdout:gsub('\n', ''))
     end
   else
-    vim.health.warn('uv not found (install https://docs.astral.sh/uv/ for scraping)')
-  end
+    if vim.fn.executable('uv') == 1 then
+      vim.health.ok('uv executable found')
+      local r = vim.system({ 'uv', '--version' }, { text = true }):wait()
+      if r.code == 0 then
+        vim.health.info('uv version: ' .. r.stdout:gsub('\n', ''))
+      end
+    else
+      vim.health.warn('uv not found (install https://docs.astral.sh/uv/ for scraping)')
+    end
 
-  local plugin_path = utils.get_plugin_path()
-  local venv_dir = plugin_path .. '/.venv'
-  if vim.fn.isdirectory(venv_dir) == 1 then
-    vim.health.ok('Python virtual environment found at ' .. venv_dir)
-  else
-    vim.health.info('Python virtual environment not set up (created on first scrape)')
+    if vim.fn.executable('nix') == 1 then
+      vim.health.info('nix available but Python environment not resolved via nix')
+    end
+
+    local plugin_path = utils.get_plugin_path()
+    local venv_dir = plugin_path .. '/.venv'
+    if vim.fn.isdirectory(venv_dir) == 1 then
+      vim.health.ok('Python virtual environment found at ' .. venv_dir)
+    else
+      vim.health.info('Python virtual environment not set up (created on first scrape)')
+    end
   end
 
   local time_cap = utils.time_capability()
@@ -41,7 +58,7 @@ local function check()
     vim.health.error('GNU time not found: ' .. (time_cap.reason or ''))
   end
 
-  local timeout_cap = utils.time_capability()
+  local timeout_cap = utils.timeout_capability()
   if timeout_cap.ok then
     vim.health.ok('GNU timeout found: ' .. timeout_cap.path)
   else

lua/cp/init.lua

@@ -15,21 +15,25 @@ local initialized = false
 
 local function ensure_initialized()
   if initialized then
-    return
-  end
-  if vim.g.cp_config then
-    vim.deprecate('vim.g.cp_config', 'vim.g.cp', 'v0.7.6', 'cp.nvim', false)
-    vim.g.cp = vim.g.cp or vim.g.cp_config
+    return true
   end
   local user_config = vim.g.cp or {}
-  local config = config_module.setup(user_config)
-  config_module.set_current_config(config)
+  local ok, result = pcall(config_module.setup, user_config)
+  if not ok then
+    local msg = tostring(result):gsub('^.+:%d+: ', '')
+    vim.notify(msg, vim.log.levels.ERROR)
+    return false
+  end
+  config_module.set_current_config(result)
   initialized = true
+  return true
 end
 
 ---@return nil
 function M.handle_command(opts)
-  ensure_initialized()
+  if not ensure_initialized() then
+    return
+  end
   local commands = require('cp.commands')
   commands.handle_command(opts)
 end
@@ -40,7 +44,7 @@ end
 
 ---@deprecated Use `vim.g.cp` instead
 function M.setup(user_config)
-  vim.deprecate('require("cp").setup()', 'vim.g.cp', 'v0.1.0', 'cp.nvim', false)
+  vim.deprecate('require("cp").setup()', 'vim.g.cp', 'v0.7.7', 'cp.nvim', false)
 
   if user_config then
     vim.g.cp = vim.tbl_deep_extend('force', vim.g.cp or {}, user_config)

lua/cp/runner/execute.lua

@@ -43,6 +43,7 @@ end
 function M.compile(compile_cmd, substitutions, on_complete)
   local cmd = substitute_template(compile_cmd, substitutions)
   local sh = table.concat(cmd, ' ') .. ' 2>&1'
+  logger.log('compile: ' .. sh)
 
   local t0 = vim.uv.hrtime()
   vim.system({ 'sh', '-c', sh }, { text = false }, function(r)
@@ -119,6 +120,7 @@ function M.run(cmd, stdin, timeout_ms, memory_mb, on_complete)
   local sec = math.ceil(timeout_ms / 1000)
   local timeout_prefix = ('%s -k 1s %ds '):format(timeout_bin, sec)
   local sh = prefix .. timeout_prefix .. ('%s -v sh -c %q 2>&1'):format(time_bin, prog)
+  logger.log('run: ' .. sh)
 
   local t0 = vim.uv.hrtime()
   vim.system({ 'sh', '-c', sh }, { stdin = stdin, text = true }, function(r)

lua/cp/scraper.lua

@@ -25,10 +25,22 @@ end
 ---@param args string[]
 ---@param opts { sync?: boolean, ndjson?: boolean, on_event?: fun(ev: table), on_exit?: fun(result: table) }
 local function run_scraper(platform, subcommand, args, opts)
+  if not utils.setup_python_env() then
+    local msg = 'no Python environment available (install uv or nix)'
+    logger.log(msg, vim.log.levels.ERROR)
+    if opts and opts.on_exit then
+      opts.on_exit({ success = false, error = msg })
+    end
+    return { success = false, error = msg }
+  end
+
   local plugin_path = utils.get_plugin_path()
-  local cmd = { 'uv', 'run', '--directory', plugin_path, '-m', 'scrapers.' .. platform, subcommand }
+  local cmd = utils.get_python_cmd(platform, plugin_path)
+  vim.list_extend(cmd, { subcommand })
   vim.list_extend(cmd, args)
 
+  logger.log('scraper cmd: ' .. table.concat(cmd, ' '))
+
   local env = vim.fn.environ()
   env.VIRTUAL_ENV = ''
   env.PYTHONPATH = ''
@@ -41,31 +53,32 @@ local function run_scraper(platform, subcommand, args, opts)
     local buf = ''
 
     local handle
-    handle = uv.spawn(
-      cmd[1],
-      { args = vim.list_slice(cmd, 2), stdio = { nil, stdout, stderr }, env = env },
-      function(code, signal)
-        if buf ~= '' and opts.on_event then
-          local ok_tail, ev_tail = pcall(vim.json.decode, buf)
-          if ok_tail then
-            opts.on_event(ev_tail)
-          end
-          buf = ''
-        end
-        if opts.on_exit then
-          opts.on_exit({ success = (code == 0), code = code, signal = signal })
-        end
-        if not stdout:is_closing() then
-          stdout:close()
-        end
-        if not stderr:is_closing() then
-          stderr:close()
-        end
-        if handle and not handle:is_closing() then
-          handle:close()
+    handle = uv.spawn(cmd[1], {
+      args = vim.list_slice(cmd, 2),
+      stdio = { nil, stdout, stderr },
+      env = env,
+      cwd = plugin_path,
+    }, function(code, signal)
+      if buf ~= '' and opts.on_event then
+        local ok_tail, ev_tail = pcall(vim.json.decode, buf)
+        if ok_tail then
+          opts.on_event(ev_tail)
         end
+        buf = ''
       end
-    )
+      if opts.on_exit then
+        opts.on_exit({ success = (code == 0), code = code, signal = signal })
+      end
+      if not stdout:is_closing() then
+        stdout:close()
+      end
+      if not stderr:is_closing() then
+        stderr:close()
+      end
+      if handle and not handle:is_closing() then
+        handle:close()
+      end
+    end)
 
     if not handle then
       logger.log('Failed to start scraper process', vim.log.levels.ERROR)
@@ -102,7 +115,7 @@ local function run_scraper(platform, subcommand, args, opts)
     return
   end
 
-  local sysopts = { text = true, timeout = 30000, env = env }
+  local sysopts = { text = true, timeout = 30000, env = env, cwd = plugin_path }
   if opts and opts.sync then
     local result = vim.system(cmd, sysopts):wait()
     return syshandle(result)

lua/cp/setup.lua

@@ -160,6 +160,8 @@ function M.setup_contest(platform, contest_id, problem_id, language)
     vim.bo[bufnr].buftype = ''
     vim.bo[bufnr].swapfile = false
 
+    state.set_language(lang)
+
     if cfg.hooks and cfg.hooks.setup_code and not vim.b[bufnr].cp_setup_done then
       local ok = pcall(cfg.hooks.setup_code, state)
       if ok then

lua/cp/ui/views.lua

@@ -121,13 +121,22 @@ function M.toggle_interactive(interactor_cmd)
       end
       local orchestrator =
         vim.fn.fnamemodify(utils.get_plugin_path() .. '/scripts/interact.py', ':p')
-      cmdline = table.concat({
-        'uv',
-        'run',
-        vim.fn.shellescape(orchestrator),
-        vim.fn.shellescape(interactor),
-        vim.fn.shellescape(binary),
-      }, ' ')
+      if utils.is_nix_build() then
+        cmdline = table.concat({
+          vim.fn.shellescape(utils.get_nix_python()),
+          vim.fn.shellescape(orchestrator),
+          vim.fn.shellescape(interactor),
+          vim.fn.shellescape(binary),
+        }, ' ')
+      else
+        cmdline = table.concat({
+          'uv',
+          'run',
+          vim.fn.shellescape(orchestrator),
+          vim.fn.shellescape(interactor),
+          vim.fn.shellescape(binary),
+        }, ' ')
+      end
     else
       cmdline = vim.fn.shellescape(binary)
     end

lua/cp/utils.lua

@@ -2,6 +2,9 @@ local M = {}
 
 local logger = require('cp.log')
 
+local _nix_python = nil
+local _nix_discovered = false
+
 local uname = vim.loop.os_uname()
 
 local _time_cached = false
@@ -57,7 +60,11 @@ local function find_gnu_time()
 
   _time_cached = true
   _time_path = nil
-  _time_reason = 'GNU time not found'
+  if uname and uname.sysname == 'Darwin' then
+    _time_reason = 'GNU time not found (install via: brew install coreutils)'
+  else
+    _time_reason = 'GNU time not found'
+  end
   return _time_path, _time_reason
 end
 
@@ -79,27 +86,101 @@ function M.get_plugin_path()
   return vim.fn.fnamemodify(plugin_path, ':h:h:h')
 end
 
+---@return boolean
+function M.is_nix_build()
+  return _nix_python ~= nil
+end
+
+---@return string|nil
+function M.get_nix_python()
+  return _nix_python
+end
+
+---@return boolean
+function M.is_nix_discovered()
+  return _nix_discovered
+end
+
+---@param module string
+---@param plugin_path string
+---@return string[]
+function M.get_python_cmd(module, plugin_path)
+  if _nix_python then
+    return { _nix_python, '-m', 'scrapers.' .. module }
+  end
+  return { 'uv', 'run', '--directory', plugin_path, '-m', 'scrapers.' .. module }
+end
+
 local python_env_setup = false
 
+---@return boolean
+local function discover_nix_python()
+  local cache_dir = vim.fn.stdpath('cache') .. '/cp-nvim'
+  local cache_file = cache_dir .. '/nix-python'
+
+  local f = io.open(cache_file, 'r')
+  if f then
+    local cached = f:read('*l')
+    f:close()
+    if cached and vim.fn.executable(cached) == 1 then
+      _nix_python = cached
+      return true
+    end
+  end
+
+  local plugin_path = M.get_plugin_path()
+  vim.notify('[cp.nvim] Building Python environment with nix...', vim.log.levels.INFO)
+  vim.cmd.redraw()
+  local result = vim
+    .system(
+      { 'nix', 'build', plugin_path .. '#pythonEnv', '--no-link', '--print-out-paths' },
+      { text = true }
+    )
+    :wait()
+
+  if result.code ~= 0 then
+    logger.log('nix build #pythonEnv failed: ' .. (result.stderr or ''), vim.log.levels.WARN)
+    return false
+  end
+
+  local store_path = result.stdout:gsub('%s+$', '')
+  local python_path = store_path .. '/bin/python3'
+
+  if vim.fn.executable(python_path) ~= 1 then
+    logger.log('nix python not executable at ' .. python_path, vim.log.levels.WARN)
+    return false
+  end
+
+  vim.fn.mkdir(cache_dir, 'p')
+  f = io.open(cache_file, 'w')
+  if f then
+    f:write(python_path)
+    f:close()
+  end
+
+  _nix_python = python_path
+  _nix_discovered = true
+  return true
+end
+
 ---@return boolean success
 function M.setup_python_env()
   if python_env_setup then
     return true
   end
 
-  local plugin_path = M.get_plugin_path()
-  local venv_dir = plugin_path .. '/.venv'
-
-  if vim.fn.executable('uv') == 0 then
-    logger.log(
-      'uv is not installed. Install it to enable problem scraping: https://docs.astral.sh/uv/',
-      vim.log.levels.WARN
-    )
-    return false
+  if _nix_python then
+    logger.log('Python env: nix (python=' .. _nix_python .. ')')
+    python_env_setup = true
+    return true
   end
 
-  if vim.fn.isdirectory(venv_dir) == 0 then
-    logger.log('Setting up Python environment for scrapers...')
+  if vim.fn.executable('uv') == 1 then
+    local plugin_path = M.get_plugin_path()
+    logger.log('Python env: uv sync (dir=' .. plugin_path .. ')')
+    vim.notify('[cp.nvim] Setting up Python environment...', vim.log.levels.INFO)
+    vim.cmd.redraw()
+
     local env = vim.fn.environ()
     env.VIRTUAL_ENV = ''
     env.PYTHONPATH = ''
@@ -108,14 +189,33 @@ function M.setup_python_env()
       .system({ 'uv', 'sync' }, { cwd = plugin_path, text = true, env = env })
       :wait()
     if result.code ~= 0 then
-      logger.log('Failed to setup Python environment: ' .. result.stderr, vim.log.levels.ERROR)
+      logger.log(
+        'Failed to setup Python environment: ' .. (result.stderr or ''),
+        vim.log.levels.ERROR
+      )
       return false
     end
-    logger.log('Python environment setup complete.')
+    if result.stderr and result.stderr ~= '' then
+      logger.log('uv sync stderr: ' .. result.stderr:gsub('%s+$', ''))
+    end
+
+    python_env_setup = true
+    return true
   end
 
-  python_env_setup = true
-  return true
+  if vim.fn.executable('nix') == 1 then
+    logger.log('Python env: nix discovery')
+    if discover_nix_python() then
+      python_env_setup = true
+      return true
+    end
+  end
+
+  logger.log(
+    'No Python environment available. Install uv (https://docs.astral.sh/uv/) or use nix.',
+    vim.log.levels.WARN
+  )
+  return false
 end
 
 --- Configure the buffer with good defaults
@@ -162,20 +262,12 @@ function M.check_required_runtime()
 
   local time = M.time_capability()
   if not time.ok then
-    return false, 'GNU time not found: ' .. (time.reason or '')
+    return false, time.reason
   end
 
   local timeout = M.timeout_capability()
   if not timeout.ok then
-    return false, 'GNU timeout not found: ' .. (timeout.reason or '')
-  end
-
-  if vim.fn.executable('uv') ~= 1 then
-    return false, 'uv not found (https://docs.astral.sh/uv/)'
-  end
-
-  if not M.setup_python_env() then
-    return false, 'failed to set up Python virtual environment'
+    return false, timeout.reason
   end
 
   return true
@@ -225,7 +317,11 @@ local function find_gnu_timeout()
 
   _timeout_cached = true
   _timeout_path = nil
-  _timeout_reason = 'GNU timeout not found'
+  if uname and uname.sysname == 'Darwin' then
+    _timeout_reason = 'GNU timeout not found (install via: brew install coreutils)'
+  else
+    _timeout_reason = 'GNU timeout not found'
+  end
   return _timeout_path, _timeout_reason
 end
 

plugin/cp.lua

@@ -154,3 +154,17 @@ end, {
     return {}
   end,
 })
+
+local function cp_action(action)
+  return function()
+    require('cp').handle_command({ fargs = { action } })
+  end
+end
+
+vim.keymap.set('n', '<Plug>(cp-run)', cp_action('run'), { desc = 'CP run tests' })
+vim.keymap.set('n', '<Plug>(cp-panel)', cp_action('panel'), { desc = 'CP open panel' })
+vim.keymap.set('n', '<Plug>(cp-edit)', cp_action('edit'), { desc = 'CP edit test cases' })
+vim.keymap.set('n', '<Plug>(cp-next)', cp_action('next'), { desc = 'CP next problem' })
+vim.keymap.set('n', '<Plug>(cp-prev)', cp_action('prev'), { desc = 'CP previous problem' })
+vim.keymap.set('n', '<Plug>(cp-pick)', cp_action('pick'), { desc = 'CP pick contest' })
+vim.keymap.set('n', '<Plug>(cp-interact)', cp_action('interact'), { desc = 'CP interactive mode' })

pyproject.toml

@@ -12,8 +12,6 @@ dependencies = [
     "ndjson>=0.3.1",
     "pydantic>=2.11.10",
     "requests>=2.32.5",
-    "scrapling[fetchers]>=0.3.5",
-    "types-requests>=2.32.4.20250913",
 ]
 
 [dependency-groups]

scrapers/codechef.py

@@ -6,7 +6,7 @@ import re
 from typing import Any
 
 import httpx
-from scrapling.fetchers import Fetcher
+from curl_cffi import requests as curl_requests
 
 from .base import BaseScraper
 from .models import (
@@ -50,8 +50,9 @@ def _extract_memory_limit(html: str) -> float:
 
 
 def _fetch_html_sync(url: str) -> str:
-    response = Fetcher.get(url)
-    return str(response.body)
+    response = curl_requests.get(url, impersonate="chrome", timeout=TIMEOUT_S)
+    response.raise_for_status()
+    return response.text
 
 
 class CodeChefScraper(BaseScraper):

scrapers/codeforces.py

@@ -2,13 +2,12 @@
 
 import asyncio
 import json
-import logging
 import re
 from typing import Any
 
 import requests
 from bs4 import BeautifulSoup, Tag
-from scrapling.fetchers import Fetcher
+from curl_cffi import requests as curl_requests
 
 from .base import BaseScraper
 from .models import (
@@ -19,10 +18,6 @@ from .models import (
     TestCase,
 )
 
-# suppress scrapling logging - https://github.com/D4Vinci/Scrapling/issues/31)
-logging.getLogger("scrapling").setLevel(logging.CRITICAL)
-
-
 BASE_URL = "https://codeforces.com"
 API_CONTEST_LIST_URL = f"{BASE_URL}/api/contest.list"
 TIMEOUT_SECONDS = 30
@@ -83,7 +78,7 @@ def _extract_title(block: Tag) -> tuple[str, str]:
 
 def _extract_samples(block: Tag) -> tuple[list[TestCase], bool]:
     st = block.find("div", class_="sample-test")
-    if not st:
+    if not isinstance(st, Tag):
         return [], False
 
     input_pres: list[Tag] = [
@@ -140,10 +135,9 @@ def _is_interactive(block: Tag) -> bool:
 
 def _fetch_problems_html(contest_id: str) -> str:
     url = f"{BASE_URL}/contest/{contest_id}/problems"
-    page = Fetcher.get(
-        url,
-    )
-    return page.html_content
+    response = curl_requests.get(url, impersonate="chrome", timeout=TIMEOUT_SECONDS)
+    response.raise_for_status()
+    return response.text
 
 
 def _parse_all_blocks(html: str) -> list[dict[str, Any]]:

tests/conftest.py

@@ -10,7 +10,7 @@ from typing import Any
 import httpx
 import pytest
 import requests
-from scrapling import fetchers
+from curl_cffi import requests as curl_requests
 
 ROOT = Path(__file__).resolve().parent.parent
 FIX = Path(__file__).resolve().parent / "fixtures"
@@ -136,12 +136,15 @@ def run_scraper_offline(fixture_text):
 
             case "codeforces":
 
-                class MockCodeForcesPage:
+                class MockCurlResponse:
                     def __init__(self, html: str):
-                        self.html_content = html
+                        self.text = html
 
-                def _mock_stealthy_fetch(url: str, **kwargs):
-                    return MockCodeForcesPage(_router_codeforces(url=url))
+                    def raise_for_status(self):
+                        pass
+
+                def _mock_curl_get(url: str, **kwargs):
+                    return MockCurlResponse(_router_codeforces(url=url))
 
                 def _mock_requests_get(url: str, **kwargs):
                     if "api/contest.list" in url:
@@ -172,7 +175,7 @@ def run_scraper_offline(fixture_text):
                     raise AssertionError(f"Unexpected requests.get call: {url}")
 
                 return {
-                    "Fetcher.get": _mock_stealthy_fetch,
+                    "curl_requests.get": _mock_curl_get,
                     "requests.get": _mock_requests_get,
                 }
 
@@ -212,21 +215,23 @@ def run_scraper_offline(fixture_text):
                         return MockResponse(data)
                     raise AssertionError(f"No fixture for CodeChef url={url!r}")
 
-                class MockCodeChefPage:
+                class MockCodeChefCurlResponse:
                     def __init__(self, html: str):
-                        self.body = html
-                        self.status = 200
+                        self.text = html
 
-                def _mock_stealthy_fetch(url: str, **kwargs):
+                    def raise_for_status(self):
+                        pass
+
+                def _mock_curl_get(url: str, **kwargs):
                     if "/problems/" in url:
                         problem_id = url.rstrip("/").split("/")[-1]
                         html = fixture_text(f"codechef/{problem_id}.html")
-                        return MockCodeChefPage(html)
+                        return MockCodeChefCurlResponse(html)
                     raise AssertionError(f"No fixture for CodeChef url={url!r}")
 
                 return {
                     "__offline_get_async": __offline_get_async,
-                    "Fetcher.get": _mock_stealthy_fetch,
+                    "curl_requests.get": _mock_curl_get,
                 }
 
             case _:
@@ -245,7 +250,7 @@ def run_scraper_offline(fixture_text):
         offline_fetches = _make_offline_fetches(scraper_name)
 
         if scraper_name == "codeforces":
-            fetchers.Fetcher.get = offline_fetches["Fetcher.get"]
+            curl_requests.get = offline_fetches["curl_requests.get"]
             requests.get = offline_fetches["requests.get"]
         elif scraper_name == "atcoder":
             ns._fetch = offline_fetches["_fetch"]
@@ -254,7 +259,7 @@ def run_scraper_offline(fixture_text):
             httpx.AsyncClient.get = offline_fetches["__offline_fetch_text"]
         elif scraper_name == "codechef":
             httpx.AsyncClient.get = offline_fetches["__offline_get_async"]
-            fetchers.Fetcher.get = offline_fetches["Fetcher.get"]
+            curl_requests.get = offline_fetches["curl_requests.get"]
 
         scraper_class = getattr(ns, scraper_classes[scraper_name])
         scraper = scraper_class()

tests/test_scrapers.py

@@ -6,11 +6,6 @@ from scrapers.models import (
     TestsResult,
 )
 
-MODEL_FOR_MODE = {
-    "metadata": MetadataResult,
-    "contests": ContestListResult,
-}
-
 MATRIX = {
     "cses": {
         "metadata": ("introductory_problems",),
@@ -43,17 +38,16 @@ def test_scraper_offline_fixture_matrix(run_scraper_offline, scraper, mode):
     assert rc in (0, 1), f"Bad exit code {rc}"
     assert objs, f"No JSON output for {scraper}:{mode}"
 
-    if mode in ("metadata", "contests"):
-        Model = MODEL_FOR_MODE[mode]
-        model = Model.model_validate(objs[-1])
-        assert model is not None
+    if mode == "metadata":
+        model = MetadataResult.model_validate(objs[-1])
         assert model.success is True
-        if mode == "metadata":
-            assert model.url
-            assert len(model.problems) >= 1
-            assert all(isinstance(p.id, str) and p.id for p in model.problems)
-        else:
-            assert len(model.contests) >= 1
+        assert model.url
+        assert len(model.problems) >= 1
+        assert all(isinstance(p.id, str) and p.id for p in model.problems)
+    elif mode == "contests":
+        model = ContestListResult.model_validate(objs[-1])
+        assert model.success is True
+        assert len(model.contests) >= 1
     else:
         assert len(objs) >= 1, "No test objects returned"
         validated_any = False