diff --git a/README.md b/README.md
index 2e9ee89..b31febd 100644
--- a/README.md
+++ b/README.md
@@ -28,11 +28,11 @@ cp.nvim follows a simple principle: **solve locally, submit remotely**.
 
 ### Basic Usage
 
-1. **Find a problem** on the judge website
-2. **Set up locally** with `:CP <platform> <contest> <problem>`
+1. **Find a contest or problem** on the judge website
+2. **Set up locally** with `:CP <platform> <contest> [<problem>]`
 
    ```
-   :CP codeforces 1848 A
+   :CP codeforces 1848
    ```
 
 3. **Code and test** with instant feedback and rich diffs
@@ -62,7 +62,3 @@ See [my config](https://github.com/barrett-ruth/dots/blob/main/nvim/lua/plugins/
 
 - [competitest.nvim](https://github.com/xeluxee/competitest.nvim)
 - [assistant.nvim](https://github.com/A7Lavinraj/assistant.nvim)
-
-## TODO
-
-- Windows support
diff --git a/lua/cp/cache.lua b/lua/cp/cache.lua
index 04d7dbd..c59fc61 100644
--- a/lua/cp/cache.lua
+++ b/lua/cp/cache.lua
@@ -342,4 +342,24 @@ function M.clear_contest_list(platform)
   end
 end
 
+function M.clear_all()
+  cache_data = {}
+  M.save()
+end
+
+---@param platform string
+function M.clear_platform(platform)
+  vim.validate({
+    platform = { platform, 'string' },
+  })
+
+  if cache_data[platform] then
+    cache_data[platform] = nil
+  end
+  if cache_data.contest_lists and cache_data.contest_lists[platform] then
+    cache_data.contest_lists[platform] = nil
+  end
+  M.save()
+end
+
 return M
diff --git a/lua/cp/config.lua b/lua/cp/config.lua
index 838107b..9386b75 100644
--- a/lua/cp/config.lua
+++ b/lua/cp/config.lua
@@ -101,7 +101,7 @@ M.defaults = {
   filename = nil,
   run_panel = {
     ansi = true,
-    diff_mode = 'vim',
+    diff_mode = 'git',
     next_test_key = '<c-n>',
     prev_test_key = '<c-p>',
     toggle_diff_key = 't',
@@ -178,7 +178,6 @@ function M.setup(user_config)
 
   local config = vim.tbl_deep_extend('force', M.defaults, user_config or {})
 
-  -- Validate merged config values
   vim.validate({
     before_run = {
       config.hooks.before_run,
@@ -267,12 +266,8 @@ function M.setup(user_config)
         error('No language configurations found')
       end
 
-      if vim.tbl_contains(available_langs, 'cpp') then
-        contest_config.default_language = 'cpp'
-      else
-        table.sort(available_langs)
-        contest_config.default_language = available_langs[1]
-      end
+      table.sort(available_langs)
+      contest_config.default_language = available_langs[1]
     end
   end
 
diff --git a/lua/cp/constants.lua b/lua/cp/constants.lua
index c14569b..7544435 100644
--- a/lua/cp/constants.lua
+++ b/lua/cp/constants.lua
@@ -1,7 +1,7 @@
 local M = {}
 
 M.PLATFORMS = { 'atcoder', 'codeforces', 'cses' }
-M.ACTIONS = { 'run', 'next', 'prev', 'pick' }
+M.ACTIONS = { 'run', 'next', 'prev', 'pick', 'cache' }
 
 M.PLATFORM_DISPLAY_NAMES = {
   atcoder = 'AtCoder',
diff --git a/lua/cp/init.lua b/lua/cp/init.lua
index 1c21880..c50316e 100644
--- a/lua/cp/init.lua
+++ b/lua/cp/init.lua
@@ -246,7 +246,7 @@ local function toggle_run_panel(is_debug)
   end
 
   local ctx = problem.create_context(state.platform, state.contest_id, state.problem_id, config)
-  local run = require('cp.run')
+  local run = require('cp.runner.run')
 
   if not run.load_test_cases(ctx, state) then
     logger.log('no test cases found', vim.log.levels.WARN)
@@ -270,7 +270,7 @@ local function toggle_run_panel(is_debug)
     tab_buf = tab_buf,
   }
 
-  local highlight = require('cp.highlight')
+  local highlight = require('cp.ui.highlight')
   local diff_namespace = highlight.create_namespace()
 
   local test_list_namespace = vim.api.nvim_create_namespace('cp_test_list')
@@ -294,6 +294,7 @@ local function toggle_run_panel(is_debug)
 
     vim.api.nvim_set_current_win(parent_win)
     vim.cmd.split()
+    vim.cmd('resize ' .. math.floor(vim.o.lines * 0.35))
     local actual_win = vim.api.nvim_get_current_win()
     vim.api.nvim_win_set_buf(actual_win, actual_buf)
 
@@ -341,13 +342,14 @@ local function toggle_run_panel(is_debug)
 
     vim.api.nvim_set_current_win(parent_win)
     vim.cmd.split()
+    vim.cmd('resize ' .. math.floor(vim.o.lines * 0.35))
     local diff_win = vim.api.nvim_get_current_win()
     vim.api.nvim_win_set_buf(diff_win, diff_buf)
 
     vim.api.nvim_set_option_value('filetype', 'cptest', { buf = diff_buf })
     vim.api.nvim_set_option_value('winbar', 'Expected vs Actual', { win = diff_win })
 
-    local diff_backend = require('cp.diff')
+    local diff_backend = require('cp.ui.diff')
     local backend = diff_backend.get_best_backend('git')
     local diff_result = backend.render(expected_content, actual_content)
 
@@ -375,6 +377,7 @@ local function toggle_run_panel(is_debug)
 
     vim.api.nvim_set_current_win(parent_win)
     vim.cmd.split()
+    vim.cmd('resize ' .. math.floor(vim.o.lines * 0.35))
     local win = vim.api.nvim_get_current_win()
     vim.api.nvim_win_set_buf(win, buf)
     vim.api.nvim_set_option_value('filetype', 'cptest', { buf = buf })
@@ -459,7 +462,7 @@ local function toggle_run_panel(is_debug)
           ansi_namespace
         )
       elseif desired_mode == 'git' then
-        local diff_backend = require('cp.diff')
+        local diff_backend = require('cp.ui.diff')
         local backend = diff_backend.get_best_backend('git')
         local diff_result = backend.render(expected_content, actual_content)
 
@@ -513,7 +516,7 @@ local function toggle_run_panel(is_debug)
       return
     end
 
-    local run_render = require('cp.run_render')
+    local run_render = require('cp.runner.run_render')
     run_render.setup_highlights()
 
     local test_state = run.get_run_panel_state()
@@ -573,7 +576,7 @@ local function toggle_run_panel(is_debug)
     config.hooks.before_debug(ctx)
   end
 
-  local execute = require('cp.execute')
+  local execute = require('cp.runner.execute')
   local contest_config = config.contests[state.platform]
   local compile_result = execute.compile_problem(ctx, contest_config, is_debug)
   if compile_result.success then
@@ -586,7 +589,7 @@ local function toggle_run_panel(is_debug)
 
   vim.schedule(function()
     if config.run_panel.ansi then
-      local ansi = require('cp.ansi')
+      local ansi = require('cp.ui.ansi')
       ansi.setup_highlight_groups()
     end
     if current_diff_layout then
@@ -600,7 +603,10 @@ local function toggle_run_panel(is_debug)
   state.test_buffers = test_buffers
   state.test_windows = test_windows
   local test_state = run.get_run_panel_state()
-  logger.log(string.format('test panel opened (%d test cases)', #test_state.test_cases))
+  logger.log(
+    string.format('test panel opened (%d test cases)', #test_state.test_cases),
+    vim.log.levels.INFO
+  )
 end
 
 ---@param contest_id string
@@ -751,6 +757,29 @@ local function handle_pick_action()
   end
 end
 
+local function handle_cache_command(cmd)
+  if cmd.subcommand == 'clear' then
+    cache.load()
+    if cmd.platform then
+      if vim.tbl_contains(platforms, cmd.platform) then
+        cache.clear_platform(cmd.platform)
+        logger.log(('cleared cache for %s'):format(cmd.platform), vim.log.levels.INFO, true)
+      else
+        logger.log(
+          ('unknown platform: %s. Available: %s'):format(
+            cmd.platform,
+            table.concat(platforms, ', ')
+          ),
+          vim.log.levels.ERROR
+        )
+      end
+    else
+      cache.clear_all()
+      logger.log('cleared all cache', vim.log.levels.INFO, true)
+    end
+  end
+end
+
 local function restore_from_current_file()
   local current_file = vim.fn.expand('%:p')
   if current_file == '' then
@@ -820,7 +849,24 @@ local function parse_command(args)
   local first = filtered_args[1]
 
   if vim.tbl_contains(actions, first) then
-    return { type = 'action', action = first, language = language, debug = debug }
+    if first == 'cache' then
+      local subcommand = filtered_args[2]
+      if not subcommand then
+        return { type = 'error', message = 'cache command requires subcommand: clear' }
+      end
+      if subcommand == 'clear' then
+        local platform = filtered_args[3]
+        return {
+          type = 'cache',
+          subcommand = 'clear',
+          platform = platform,
+        }
+      else
+        return { type = 'error', message = 'unknown cache subcommand: ' .. subcommand }
+      end
+    else
+      return { type = 'action', action = first, language = language, debug = debug }
+    end
   end
 
   if vim.tbl_contains(platforms, first) then
@@ -896,6 +942,11 @@ function M.handle_command(opts)
     return
   end
 
+  if cmd.type == 'cache' then
+    handle_cache_command(cmd)
+    return
+  end
+
   if cmd.type == 'platform_only' then
     set_platform(cmd.platform)
     return
@@ -929,7 +980,9 @@ function M.handle_command(opts)
             #metadata_result.problems,
             cmd.platform,
             cmd.contest
-          )
+          ),
+          vim.log.levels.INFO,
+          true
         )
         problem_ids = vim.tbl_map(function(prob)
           return prob.id
diff --git a/lua/cp/pickers/init.lua b/lua/cp/pickers/init.lua
index 5a1b644..b981b59 100644
--- a/lua/cp/pickers/init.lua
+++ b/lua/cp/pickers/init.lua
@@ -159,8 +159,10 @@ end
 ---@param contest_id string Contest identifier
 ---@param problem_id string Problem identifier
 local function setup_problem(platform, contest_id, problem_id)
-  local cp = require('cp')
-  cp.handle_command({ fargs = { platform, contest_id, problem_id } })
+  vim.schedule(function()
+    local cp = require('cp')
+    cp.handle_command({ fargs = { platform, contest_id, problem_id } })
+  end)
 end
 
 M.get_platforms = get_platforms
diff --git a/lua/cp/execute.lua b/lua/cp/runner/execute.lua
similarity index 97%
rename from lua/cp/execute.lua
rename to lua/cp/runner/execute.lua
index 1c433d6..62c0f99 100644
--- a/lua/cp/execute.lua
+++ b/lua/cp/runner/execute.lua
@@ -89,12 +89,12 @@ function M.compile_generic(language_config, substitutions)
     :wait()
   local compile_time = (vim.uv.hrtime() - start_time) / 1000000
 
-  local ansi = require('cp.ansi')
+  local ansi = require('cp.ui.ansi')
   result.stdout = ansi.bytes_to_string(result.stdout or '')
   result.stderr = ansi.bytes_to_string(result.stderr or '')
 
   if result.code == 0 then
-    logger.log(('compilation successful (%.1fms)'):format(compile_time))
+    logger.log(('compilation successful (%.1fms)'):format(compile_time), vim.log.levels.INFO)
   else
     logger.log(('compilation failed (%.1fms)'):format(compile_time))
   end
@@ -235,7 +235,10 @@ function M.compile_problem(ctx, contest_config, is_debug)
     if compile_result.code ~= 0 then
       return { success = false, output = compile_result.stdout or 'unknown error' }
     end
-    logger.log(('compilation successful (%s)'):format(is_debug and 'debug mode' or 'test mode'))
+    logger.log(
+      ('compilation successful (%s)'):format(is_debug and 'debug mode' or 'test mode'),
+      vim.log.levels.INFO
+    )
   end
 
   return { success = true, output = nil }
diff --git a/lua/cp/run.lua b/lua/cp/runner/run.lua
similarity index 98%
rename from lua/cp/run.lua
rename to lua/cp/runner/run.lua
index ddd2346..f996a60 100644
--- a/lua/cp/run.lua
+++ b/lua/cp/runner/run.lua
@@ -194,7 +194,7 @@ local function run_single_test_case(ctx, contest_config, cp_config, test_case)
       .system({ 'sh', '-c', table.concat(redirected_cmd, ' ') }, { text = false })
       :wait()
 
-    local ansi = require('cp.ansi')
+    local ansi = require('cp.ui.ansi')
     compile_result.stdout = ansi.bytes_to_string(compile_result.stdout or '')
     compile_result.stderr = ansi.bytes_to_string(compile_result.stderr or '')
 
@@ -234,7 +234,7 @@ local function run_single_test_case(ctx, contest_config, cp_config, test_case)
     :wait()
   local execution_time = (vim.uv.hrtime() - start_time) / 1000000
 
-  local ansi = require('cp.ansi')
+  local ansi = require('cp.ui.ansi')
   local stdout_str = ansi.bytes_to_string(result.stdout or '')
   local actual_output = stdout_str:gsub('\n$', '')
 
@@ -315,7 +315,7 @@ function M.load_test_cases(ctx, state)
         run_panel_state.constraints.memory_mb
       )
     or ''
-  logger.log(('loaded %d test case(s)%s'):format(#test_cases, constraint_info))
+  logger.log(('loaded %d test case(s)%s'):format(#test_cases, constraint_info), vim.log.levels.INFO)
   return #test_cases > 0
 end
 
@@ -365,7 +365,7 @@ function M.get_run_panel_state()
 end
 
 function M.handle_compilation_failure(compilation_output)
-  local ansi = require('cp.ansi')
+  local ansi = require('cp.ui.ansi')
   local config = require('cp.config').setup()
 
   local clean_text
diff --git a/lua/cp/run_render.lua b/lua/cp/runner/run_render.lua
similarity index 100%
rename from lua/cp/run_render.lua
rename to lua/cp/runner/run_render.lua
diff --git a/lua/cp/scrape.lua b/lua/cp/scrape.lua
index 5ecaf43..f7a48c8 100644
--- a/lua/cp/scrape.lua
+++ b/lua/cp/scrape.lua
@@ -17,7 +17,7 @@ local problem = require('cp.problem')
 local utils = require('cp.utils')
 
 local function check_internet_connectivity()
-  local result = vim.system({ 'ping', '-c', '1', '-W', '3', '8.8.8.8' }, { text = true }):wait()
+  local result = vim.system({ 'ping', '-c', '5', '-W', '3', '8.8.8.8' }, { text = true }):wait()
   return result.code == 0
 end
 
diff --git a/lua/cp/ansi.lua b/lua/cp/ui/ansi.lua
similarity index 100%
rename from lua/cp/ansi.lua
rename to lua/cp/ui/ansi.lua
diff --git a/lua/cp/diff.lua b/lua/cp/ui/diff.lua
similarity index 100%
rename from lua/cp/diff.lua
rename to lua/cp/ui/diff.lua
diff --git a/lua/cp/highlight.lua b/lua/cp/ui/highlight.lua
similarity index 100%
rename from lua/cp/highlight.lua
rename to lua/cp/ui/highlight.lua
diff --git a/lua/cp/window.lua b/lua/cp/window.lua
deleted file mode 100644
index b150965..0000000
--- a/lua/cp/window.lua
+++ /dev/null
@@ -1,145 +0,0 @@
----@class WindowState
----@field windows table<integer, WindowData>
----@field current_win integer
----@field layout string
-
----@class WindowData
----@field bufnr integer
----@field view table
----@field width integer
----@field height integer
-
-local M = {}
-local constants = require('cp.constants')
-
----@return WindowState
-function M.save_layout()
-  local windows = {}
-  for _, win in ipairs(vim.api.nvim_list_wins()) do
-    if vim.api.nvim_win_is_valid(win) then
-      local bufnr = vim.api.nvim_win_get_buf(win)
-      windows[win] = {
-        bufnr = bufnr,
-        view = vim.fn.winsaveview(),
-        width = vim.api.nvim_win_get_width(win),
-        height = vim.api.nvim_win_get_height(win),
-      }
-    end
-  end
-
-  return {
-    windows = windows,
-    current_win = vim.api.nvim_get_current_win(),
-    layout = vim.fn.winrestcmd(),
-  }
-end
-
----@param state? WindowState
----@param tile_fn? fun(source_buf: integer, input_buf: integer, output_buf: integer)
-function M.restore_layout(state, tile_fn)
-  vim.validate({
-    state = { state, { 'table', 'nil' }, true },
-    tile_fn = { tile_fn, { 'function', 'nil' }, true },
-  })
-
-  if not state then
-    return
-  end
-
-  vim.cmd.diffoff()
-
-  local problem_id = vim.fn.expand('%:t:r')
-  if problem_id == '' then
-    for win, win_state in pairs(state.windows) do
-      if vim.api.nvim_win_is_valid(win) and vim.api.nvim_buf_is_valid(win_state.bufnr) then
-        local bufname = vim.api.nvim_buf_get_name(win_state.bufnr)
-        if
-          not bufname:match('%.in$')
-          and not bufname:match('%.out$')
-          and not bufname:match('%.expected$')
-        then
-          problem_id = vim.fn.fnamemodify(bufname, ':t:r')
-          break
-        end
-      end
-    end
-  end
-
-  if problem_id ~= '' then
-    vim.cmd('silent only')
-
-    local base_fp = vim.fn.getcwd()
-    local input_file = ('%s/io/%s.in'):format(base_fp, problem_id)
-    local output_file = ('%s/io/%s.out'):format(base_fp, problem_id)
-    local source_files = vim.fn.glob(problem_id .. '.*')
-    local source_file
-    if source_files ~= '' then
-      local files = vim.split(source_files, '\n')
-      -- Prefer known extensions first, but accept any extension
-      local known_extensions = vim.tbl_keys(constants.filetype_to_language)
-      for _, file in ipairs(files) do
-        local ext = vim.fn.fnamemodify(file, ':e')
-        if vim.tbl_contains(known_extensions, ext) then
-          source_file = file
-          break
-        end
-      end
-      source_file = source_file or files[1]
-    end
-
-    if not source_file or vim.fn.filereadable(source_file) == 0 then
-      return
-    end
-
-    vim.cmd.edit(source_file)
-    local source_buf = vim.api.nvim_get_current_buf()
-    local input_buf = vim.fn.bufnr(input_file, true)
-    local output_buf = vim.fn.bufnr(output_file, true)
-
-    if tile_fn then
-      tile_fn(source_buf, input_buf, output_buf)
-    else
-      M.default_tile(source_buf, input_buf, output_buf)
-    end
-  else
-    vim.cmd(state.layout)
-
-    for win, win_state in pairs(state.windows) do
-      if vim.api.nvim_win_is_valid(win) then
-        vim.api.nvim_set_current_win(win)
-        if vim.api.nvim_get_current_buf() == win_state.bufnr then
-          vim.fn.winrestview(win_state.view)
-        end
-      end
-    end
-
-    if vim.api.nvim_win_is_valid(state.current_win) then
-      vim.api.nvim_set_current_win(state.current_win)
-    end
-  end
-end
-
----@param source_buf integer
----@param input_buf integer
----@param output_buf integer
-local function default_tile(source_buf, input_buf, output_buf)
-  vim.validate({
-    source_buf = { source_buf, 'number' },
-    input_buf = { input_buf, 'number' },
-    output_buf = { output_buf, 'number' },
-  })
-
-  vim.api.nvim_set_current_buf(source_buf)
-  vim.cmd.vsplit()
-  vim.api.nvim_set_current_buf(output_buf)
-  vim.bo.filetype = 'cp'
-  vim.cmd(('vertical resize %d'):format(math.floor(vim.o.columns * 0.3)))
-  vim.cmd.split()
-  vim.api.nvim_set_current_buf(input_buf)
-  vim.bo.filetype = 'cp'
-  vim.cmd.wincmd('h')
-end
-
-M.default_tile = default_tile
-
-return M
diff --git a/plugin/cp.lua b/plugin/cp.lua
index 2bf4707..da193dc 100644
--- a/plugin/cp.lua
+++ b/plugin/cp.lua
@@ -36,12 +36,24 @@ end, {
         end
       else
         vim.list_extend(candidates, platforms)
+        table.insert(candidates, 'cache')
+        table.insert(candidates, 'pick')
       end
       return vim.tbl_filter(function(cmd)
         return cmd:find(ArgLead, 1, true) == 1
       end, candidates)
+    elseif num_args == 3 then
+      if args[2] == 'cache' then
+        return vim.tbl_filter(function(cmd)
+          return cmd:find(ArgLead, 1, true) == 1
+        end, { 'clear' })
+      end
     elseif num_args == 4 then
-      if vim.tbl_contains(platforms, args[2]) then
+      if args[2] == 'cache' and args[3] == 'clear' then
+        return vim.tbl_filter(function(cmd)
+          return cmd:find(ArgLead, 1, true) == 1
+        end, platforms)
+      elseif vim.tbl_contains(platforms, args[2]) then
         local cache = require('cp.cache')
         cache.load()
         local contest_data = cache.get_contest_data(args[2], args[3])
diff --git a/scrapers/atcoder.py b/scrapers/atcoder.py
index 83e1cc1..1935c6e 100644
--- a/scrapers/atcoder.py
+++ b/scrapers/atcoder.py
@@ -272,75 +272,7 @@ def scrape_contests() -> list[ContestSummary]:
                 r"[\uff01-\uff5e]", lambda m: chr(ord(m.group()) - 0xFEE0), name
             )
 
-            def generate_display_name_from_id(contest_id: str) -> str:
-                parts = contest_id.replace("-", " ").replace("_", " ")
-
-                parts = re.sub(
-                    r"\b(jsc|JSC)\b",
-                    "Japanese Student Championship",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-                parts = re.sub(
-                    r"\b(wtf|WTF)\b",
-                    "World Tour Finals",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-                parts = re.sub(
-                    r"\b(ahc)(\d+)\b",
-                    r"Heuristic Contest \2 (AHC)",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-                parts = re.sub(
-                    r"\b(arc)(\d+)\b",
-                    r"Regular Contest \2 (ARC)",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-                parts = re.sub(
-                    r"\b(abc)(\d+)\b",
-                    r"Beginner Contest \2 (ABC)",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-                parts = re.sub(
-                    r"\b(agc)(\d+)\b",
-                    r"Grand Contest \2 (AGC)",
-                    parts,
-                    flags=re.IGNORECASE,
-                )
-
-                return parts.title()
-
-            english_chars = sum(1 for c in name if c.isascii() and c.isalpha())
-            total_chars = len(re.sub(r"\s+", "", name))
-
-            if total_chars > 0 and english_chars / total_chars < 0.3:
-                display_name = generate_display_name_from_id(contest_id)
-            else:
-                display_name = name
-                if "AtCoder Beginner Contest" in name:
-                    match = re.search(r"AtCoder Beginner Contest (\d+)", name)
-                    if match:
-                        display_name = f"Beginner Contest {match.group(1)} (ABC)"
-                elif "AtCoder Regular Contest" in name:
-                    match = re.search(r"AtCoder Regular Contest (\d+)", name)
-                    if match:
-                        display_name = f"Regular Contest {match.group(1)} (ARC)"
-                elif "AtCoder Grand Contest" in name:
-                    match = re.search(r"AtCoder Grand Contest (\d+)", name)
-                    if match:
-                        display_name = f"Grand Contest {match.group(1)} (AGC)"
-                elif "AtCoder Heuristic Contest" in name:
-                    match = re.search(r"AtCoder Heuristic Contest (\d+)", name)
-                    if match:
-                        display_name = f"Heuristic Contest {match.group(1)} (AHC)"
-
-            contests.append(
-                ContestSummary(id=contest_id, name=name, display_name=display_name)
-            )
+            contests.append(ContestSummary(id=contest_id, name=name, display_name=name))
 
         return contests
 
diff --git a/scrapers/codeforces.py b/scrapers/codeforces.py
index 1402827..89d568e 100644
--- a/scrapers/codeforces.py
+++ b/scrapers/codeforces.py
@@ -237,45 +237,9 @@ def scrape_contests() -> list[ContestSummary]:
             contest_id = str(contest["id"])
             name = contest["name"]
 
-            display_name = name
-            if "Educational Codeforces Round" in name:
-                match = re.search(r"Educational Codeforces Round (\d+)", name)
-                if match:
-                    display_name = f"Educational Round {match.group(1)}"
-            elif "Codeforces Global Round" in name:
-                match = re.search(r"Codeforces Global Round (\d+)", name)
-                if match:
-                    display_name = f"Global Round {match.group(1)}"
-            elif "Codeforces Round" in name:
-                div_match = re.search(r"Codeforces Round (\d+) \(Div\. (\d+)\)", name)
-                if div_match:
-                    display_name = (
-                        f"Round {div_match.group(1)} (Div. {div_match.group(2)})"
-                    )
-                else:
-                    combined_match = re.search(
-                        r"Codeforces Round (\d+) \(Div\. 1 \+ Div\. 2\)", name
-                    )
-                    if combined_match:
-                        display_name = (
-                            f"Round {combined_match.group(1)} (Div. 1 + Div. 2)"
-                        )
-                    else:
-                        single_div_match = re.search(
-                            r"Codeforces Round (\d+) \(Div\. 1\)", name
-                        )
-                        if single_div_match:
-                            display_name = f"Round {single_div_match.group(1)} (Div. 1)"
-                        else:
-                            round_match = re.search(r"Codeforces Round (\d+)", name)
-                            if round_match:
-                                display_name = f"Round {round_match.group(1)}"
+            contests.append(ContestSummary(id=contest_id, name=name, display_name=name))
 
-            contests.append(
-                ContestSummary(id=contest_id, name=name, display_name=display_name)
-            )
-
-        return contests[:100]
+        return contests
 
     except Exception as e:
         print(f"Failed to fetch contests: {e}", file=sys.stderr)
diff --git a/spec/ansi_spec.lua b/spec/ansi_spec.lua
index ff7a96b..af62c36 100644
--- a/spec/ansi_spec.lua
+++ b/spec/ansi_spec.lua
@@ -1,5 +1,5 @@
 describe('ansi parser', function()
-  local ansi = require('cp.ansi')
+  local ansi = require('cp.ui.ansi')
 
   describe('bytes_to_string', function()
     it('returns string as-is', function()
@@ -224,7 +224,6 @@ describe('ansi parser', function()
       ansi.setup_highlight_groups()
 
       local highlight = vim.api.nvim_get_hl(0, { name = 'CpAnsiRed' })
-      -- When 'NONE' is set, nvim_get_hl returns nil for that field
       assert.is_nil(highlight.fg)
 
       for i = 0, 15 do
diff --git a/spec/cache_spec.lua b/spec/cache_spec.lua
index 5b06911..a72946a 100644
--- a/spec/cache_spec.lua
+++ b/spec/cache_spec.lua
@@ -156,4 +156,38 @@ describe('cp.cache', function()
       assert.equals('python', result.language)
     end)
   end)
+
+  describe('cache management', function()
+    it('clears all cache data', function()
+      cache.set_contest_data('atcoder', 'test_contest', { { id = 'A' } })
+      cache.set_contest_data('codeforces', 'test_contest', { { id = 'B' } })
+      cache.set_file_state('/tmp/test.cpp', 'atcoder', 'abc123', 'a', 'cpp')
+
+      cache.clear_all()
+
+      assert.is_nil(cache.get_contest_data('atcoder', 'test_contest'))
+      assert.is_nil(cache.get_contest_data('codeforces', 'test_contest'))
+      assert.is_nil(cache.get_file_state('/tmp/test.cpp'))
+    end)
+
+    it('clears cache for specific platform', function()
+      cache.set_contest_data('atcoder', 'test_contest', { { id = 'A' } })
+      cache.set_contest_data('codeforces', 'test_contest', { { id = 'B' } })
+      cache.set_contest_list('atcoder', { { id = '123', name = 'Test' } })
+      cache.set_contest_list('codeforces', { { id = '456', name = 'Test' } })
+
+      cache.clear_platform('atcoder')
+
+      assert.is_nil(cache.get_contest_data('atcoder', 'test_contest'))
+      assert.is_nil(cache.get_contest_list('atcoder'))
+      assert.is_not_nil(cache.get_contest_data('codeforces', 'test_contest'))
+      assert.is_not_nil(cache.get_contest_list('codeforces'))
+    end)
+
+    it('handles clear platform for non-existent platform', function()
+      assert.has_no_errors(function()
+        cache.clear_platform('nonexistent')
+      end)
+    end)
+  end)
 end)
diff --git a/spec/command_parsing_spec.lua b/spec/command_parsing_spec.lua
index 2d856c6..693f2b2 100644
--- a/spec/command_parsing_spec.lua
+++ b/spec/command_parsing_spec.lua
@@ -293,4 +293,345 @@ describe('cp command parsing', function()
       end
     end)
   end)
+
+  describe('cache commands', function()
+    it('handles cache clear without platform', function()
+      local opts = { fargs = { 'cache', 'clear' } }
+
+      assert.has_no_errors(function()
+        cp.handle_command(opts)
+      end)
+
+      local success_logged = false
+      for _, log_entry in ipairs(logged_messages) do
+        if log_entry.msg and log_entry.msg:match('cleared all cache') then
+          success_logged = true
+          break
+        end
+      end
+      assert.is_true(success_logged)
+    end)
+
+    it('handles cache clear with valid platform', function()
+      local opts = { fargs = { 'cache', 'clear', 'atcoder' } }
+
+      assert.has_no_errors(function()
+        cp.handle_command(opts)
+      end)
+
+      local success_logged = false
+      for _, log_entry in ipairs(logged_messages) do
+        if log_entry.msg and log_entry.msg:match('cleared cache for atcoder') then
+          success_logged = true
+          break
+        end
+      end
+      assert.is_true(success_logged)
+    end)
+
+    it('logs error for cache clear with invalid platform', function()
+      local opts = { fargs = { 'cache', 'clear', 'invalid_platform' } }
+
+      cp.handle_command(opts)
+
+      local error_logged = false
+      for _, log_entry in ipairs(logged_messages) do
+        if log_entry.level == vim.log.levels.ERROR and log_entry.msg:match('unknown platform') then
+          error_logged = true
+          break
+        end
+      end
+      assert.is_true(error_logged)
+    end)
+
+    it('logs error for cache command without subcommand', function()
+      local opts = { fargs = { 'cache' } }
+
+      cp.handle_command(opts)
+
+      local error_logged = false
+      for _, log_entry in ipairs(logged_messages) do
+        if
+          log_entry.level == vim.log.levels.ERROR
+          and log_entry.msg:match('cache command requires subcommand')
+        then
+          error_logged = true
+          break
+        end
+      end
+      assert.is_true(error_logged)
+    end)
+
+    it('logs error for invalid cache subcommand', function()
+      local opts = { fargs = { 'cache', 'invalid' } }
+
+      cp.handle_command(opts)
+
+      local error_logged = false
+      for _, log_entry in ipairs(logged_messages) do
+        if
+          log_entry.level == vim.log.levels.ERROR
+          and log_entry.msg:match('unknown cache subcommand')
+        then
+          error_logged = true
+          break
+        end
+      end
+      assert.is_true(error_logged)
+    end)
+  end)
+
+  describe('CP command completion', function()
+    local complete_fn
+
+    before_each(function()
+      package.loaded['cp'] = nil
+      package.loaded['cp.cache'] = nil
+
+      complete_fn = function(ArgLead, CmdLine, _)
+        local constants = require('cp.constants')
+        local platforms = constants.PLATFORMS
+        local actions = constants.ACTIONS
+
+        local args = vim.split(vim.trim(CmdLine), '%s+')
+        local num_args = #args
+        if CmdLine:sub(-1) == ' ' then
+          num_args = num_args + 1
+        end
+
+        if num_args == 2 then
+          local candidates = {}
+          local cp_mod = require('cp')
+          local context = cp_mod.get_current_context()
+          if context.platform and context.contest_id then
+            vim.list_extend(candidates, actions)
+            local cache = require('cp.cache')
+            cache.load()
+            local contest_data = cache.get_contest_data(context.platform, context.contest_id)
+            if contest_data and contest_data.problems then
+              for _, problem in ipairs(contest_data.problems) do
+                table.insert(candidates, problem.id)
+              end
+            end
+          else
+            vim.list_extend(candidates, platforms)
+            table.insert(candidates, 'cache')
+            table.insert(candidates, 'pick')
+          end
+          return vim.tbl_filter(function(cmd)
+            return cmd:find(ArgLead, 1, true) == 1
+          end, candidates)
+        elseif num_args == 3 then
+          if args[2] == 'cache' then
+            return vim.tbl_filter(function(cmd)
+              return cmd:find(ArgLead, 1, true) == 1
+            end, { 'clear' })
+          end
+        elseif num_args == 4 then
+          if args[2] == 'cache' and args[3] == 'clear' then
+            return vim.tbl_filter(function(cmd)
+              return cmd:find(ArgLead, 1, true) == 1
+            end, platforms)
+          elseif vim.tbl_contains(platforms, args[2]) then
+            local cache = require('cp.cache')
+            cache.load()
+            local contest_data = cache.get_contest_data(args[2], args[3])
+            if contest_data and contest_data.problems then
+              local candidates = {}
+              for _, problem in ipairs(contest_data.problems) do
+                table.insert(candidates, problem.id)
+              end
+              return vim.tbl_filter(function(cmd)
+                return cmd:find(ArgLead, 1, true) == 1
+              end, candidates)
+            end
+          end
+        end
+        return {}
+      end
+
+      package.loaded['cp'] = {
+        get_current_context = function()
+          return { platform = nil, contest_id = nil }
+        end,
+      }
+
+      package.loaded['cp.cache'] = {
+        load = function() end,
+        get_contest_data = function()
+          return nil
+        end,
+      }
+    end)
+
+    after_each(function()
+      package.loaded['cp'] = nil
+      package.loaded['cp.cache'] = nil
+    end)
+
+    it('completes platforms and global actions when no contest context', function()
+      local result = complete_fn('', 'CP ', 3)
+
+      assert.is_table(result)
+
+      local has_atcoder = false
+      local has_codeforces = false
+      local has_cses = false
+      local has_cache = false
+      local has_pick = false
+      local has_run = false
+      local has_next = false
+      local has_prev = false
+
+      for _, item in ipairs(result) do
+        if item == 'atcoder' then
+          has_atcoder = true
+        end
+        if item == 'codeforces' then
+          has_codeforces = true
+        end
+        if item == 'cses' then
+          has_cses = true
+        end
+        if item == 'cache' then
+          has_cache = true
+        end
+        if item == 'pick' then
+          has_pick = true
+        end
+        if item == 'run' then
+          has_run = true
+        end
+        if item == 'next' then
+          has_next = true
+        end
+        if item == 'prev' then
+          has_prev = true
+        end
+      end
+
+      assert.is_true(has_atcoder)
+      assert.is_true(has_codeforces)
+      assert.is_true(has_cses)
+      assert.is_true(has_cache)
+      assert.is_true(has_pick)
+      assert.is_false(has_run)
+      assert.is_false(has_next)
+      assert.is_false(has_prev)
+    end)
+
+    it('completes all actions and problems when contest context exists', function()
+      package.loaded['cp'] = {
+        get_current_context = function()
+          return { platform = 'atcoder', contest_id = 'abc350' }
+        end,
+      }
+      package.loaded['cp.cache'] = {
+        load = function() end,
+        get_contest_data = function()
+          return {
+            problems = {
+              { id = 'a' },
+              { id = 'b' },
+              { id = 'c' },
+            },
+          }
+        end,
+      }
+
+      local result = complete_fn('', 'CP ', 3)
+
+      assert.is_table(result)
+
+      local items = {}
+      for _, item in ipairs(result) do
+        items[item] = true
+      end
+
+      assert.is_true(items['run'])
+      assert.is_true(items['next'])
+      assert.is_true(items['prev'])
+      assert.is_true(items['pick'])
+      assert.is_true(items['cache'])
+
+      assert.is_true(items['a'])
+      assert.is_true(items['b'])
+      assert.is_true(items['c'])
+    end)
+
+    it('completes cache subcommands', function()
+      local result = complete_fn('c', 'CP cache c', 10)
+
+      assert.is_table(result)
+      assert.equals(1, #result)
+      assert.equals('clear', result[1])
+    end)
+
+    it('completes cache subcommands with exact match', function()
+      local result = complete_fn('clear', 'CP cache clear', 14)
+
+      assert.is_table(result)
+      assert.equals(1, #result)
+      assert.equals('clear', result[1])
+    end)
+
+    it('completes platforms for cache clear', function()
+      local result = complete_fn('a', 'CP cache clear a', 16)
+
+      assert.is_table(result)
+
+      local has_atcoder = false
+      local has_cache = false
+
+      for _, item in ipairs(result) do
+        if item == 'atcoder' then
+          has_atcoder = true
+        end
+        if item == 'cache' then
+          has_cache = true
+        end
+      end
+
+      assert.is_true(has_atcoder)
+      assert.is_false(has_cache)
+    end)
+
+    it('filters completions based on current input', function()
+      local result = complete_fn('at', 'CP at', 5)
+
+      assert.is_table(result)
+      assert.equals(1, #result)
+      assert.equals('atcoder', result[1])
+    end)
+
+    it('returns empty array when no matches', function()
+      local result = complete_fn('xyz', 'CP xyz', 6)
+
+      assert.is_table(result)
+      assert.equals(0, #result)
+    end)
+
+    it('handles problem completion for platform contest', function()
+      package.loaded['cp.cache'] = {
+        load = function() end,
+        get_contest_data = function(platform, contest)
+          if platform == 'atcoder' and contest == 'abc350' then
+            return {
+              problems = {
+                { id = 'a' },
+                { id = 'b' },
+              },
+            }
+          end
+          return nil
+        end,
+      }
+
+      local result = complete_fn('a', 'CP atcoder abc350 a', 18)
+
+      assert.is_table(result)
+      assert.equals(1, #result)
+      assert.equals('a', result[1])
+    end)
+  end)
 end)
diff --git a/spec/config_spec.lua b/spec/config_spec.lua
index f3f3738..9724832 100644
--- a/spec/config_spec.lua
+++ b/spec/config_spec.lua
@@ -169,7 +169,7 @@ describe('cp.config', function()
         assert.equals('cpp', result.contests.test.default_language)
       end)
 
-      it('sets default_language to first available when cpp not present', function()
+      it('sets default_language to single available language when only one configured', function()
         local user_config = {
           contests = {
             test = {
@@ -183,6 +183,38 @@ describe('cp.config', function()
         assert.equals('python', result.contests.test.default_language)
       end)
 
+      it('sets default_language to single available language even when not cpp', function()
+        local user_config = {
+          contests = {
+            test = {
+              rust = {
+                test = { './target/release/solution' },
+                extension = 'rs',
+              },
+            },
+          },
+        }
+
+        local result = config.setup(user_config)
+
+        assert.equals('rust', result.contests.test.default_language)
+      end)
+
+      it('uses first available language when multiple configured', function()
+        local user_config = {
+          contests = {
+            test = {
+              python = { test = { 'python3' } },
+              cpp = { compile = { 'g++' } },
+            },
+          },
+        }
+
+        local result = config.setup(user_config)
+
+        assert.is_true(vim.tbl_contains({ 'cpp', 'python' }, result.contests.test.default_language))
+      end)
+
       it('preserves explicit default_language', function()
         local user_config = {
           contests = {
diff --git a/spec/diff_spec.lua b/spec/diff_spec.lua
index 9bb8b63..b50d05e 100644
--- a/spec/diff_spec.lua
+++ b/spec/diff_spec.lua
@@ -4,7 +4,7 @@ describe('cp.diff', function()
 
   before_each(function()
     spec_helper.setup()
-    diff = require('cp.diff')
+    diff = require('cp.ui.diff')
   end)
 
   after_each(function()
diff --git a/spec/execute_spec.lua b/spec/execute_spec.lua
index 12e7f67..38784be 100644
--- a/spec/execute_spec.lua
+++ b/spec/execute_spec.lua
@@ -6,7 +6,7 @@ describe('cp.execute', function()
 
   before_each(function()
     spec_helper.setup()
-    execute = require('cp.execute')
+    execute = require('cp.runner.execute')
     mock_system_calls = {}
     temp_files = {}
 
@@ -416,7 +416,7 @@ describe('cp.execute', function()
         }
       end
 
-      local execute_command = require('cp.execute').execute_command
+      local execute_command = require('cp.runner.execute').execute_command
         or function(command, stdin_data, timeout)
           local redirected_cmd = vim.deepcopy(command)
           if #redirected_cmd > 0 then
diff --git a/spec/extmark_spec.lua b/spec/extmark_spec.lua
index 6383d55..2b4b25a 100644
--- a/spec/extmark_spec.lua
+++ b/spec/extmark_spec.lua
@@ -4,7 +4,7 @@ describe('extmarks', function()
 
   before_each(function()
     spec_helper.setup()
-    highlight = require('cp.highlight')
+    highlight = require('cp.ui.highlight')
   end)
 
   after_each(function()
diff --git a/spec/highlight_spec.lua b/spec/highlight_spec.lua
index 74f1c91..9afd773 100644
--- a/spec/highlight_spec.lua
+++ b/spec/highlight_spec.lua
@@ -4,7 +4,7 @@ describe('cp.highlight', function()
 
   before_each(function()
     spec_helper.setup()
-    highlight = require('cp.highlight')
+    highlight = require('cp.ui.highlight')
   end)
 
   after_each(function()
diff --git a/spec/picker_spec.lua b/spec/picker_spec.lua
index ab4d36e..92b32a2 100644
--- a/spec/picker_spec.lua
+++ b/spec/picker_spec.lua
@@ -194,6 +194,10 @@ describe('cp.picker', function()
 
       picker.setup_problem('codeforces', '1951', 'a')
 
+      vim.wait(100, function()
+        return called_with ~= nil
+      end)
+
       assert.is_table(called_with)
       assert.is_table(called_with.fargs)
       assert.equals('codeforces', called_with.fargs[1])
diff --git a/spec/run_render_spec.lua b/spec/run_render_spec.lua
index bcb0c78..a647331 100644
--- a/spec/run_render_spec.lua
+++ b/spec/run_render_spec.lua
@@ -1,5 +1,5 @@
 describe('cp.run_render', function()
-  local run_render = require('cp.run_render')
+  local run_render = require('cp.runner.run_render')
   local spec_helper = require('spec.spec_helper')
 
   before_each(function()
diff --git a/spec/run_spec.lua b/spec/run_spec.lua
index e70f4f7..f7eb772 100644
--- a/spec/run_spec.lua
+++ b/spec/run_spec.lua
@@ -1,5 +1,5 @@
 describe('run module', function()
-  local run = require('cp.run')
+  local run = require('cp.runner.run')
 
   describe('basic functionality', function()
     it('has required functions', function()
diff --git a/tests/scrapers/test_atcoder.py b/tests/scrapers/test_atcoder.py
index a2a88e5..dcde406 100644
--- a/tests/scrapers/test_atcoder.py
+++ b/tests/scrapers/test_atcoder.py
@@ -101,12 +101,12 @@ def test_scrape_contests_success(mocker):
     assert result[0] == ContestSummary(
         id="abc350",
         name="AtCoder Beginner Contest 350",
-        display_name="Beginner Contest 350 (ABC)",
+        display_name="AtCoder Beginner Contest 350",
     )
     assert result[1] == ContestSummary(
         id="arc170",
         name="AtCoder Regular Contest 170",
-        display_name="Regular Contest 170 (ARC)",
+        display_name="AtCoder Regular Contest 170",
     )
 
 
diff --git a/tests/scrapers/test_codeforces.py b/tests/scrapers/test_codeforces.py
index b95a489..14b263c 100644
--- a/tests/scrapers/test_codeforces.py
+++ b/tests/scrapers/test_codeforces.py
@@ -77,15 +77,17 @@ def test_scrape_contests_success(mocker):
     assert result[0] == ContestSummary(
         id="1951",
         name="Educational Codeforces Round 168 (Rated for Div. 2)",
-        display_name="Educational Round 168",
+        display_name="Educational Codeforces Round 168 (Rated for Div. 2)",
     )
     assert result[1] == ContestSummary(
         id="1950",
         name="Codeforces Round 936 (Div. 2)",
-        display_name="Round 936 (Div. 2)",
+        display_name="Codeforces Round 936 (Div. 2)",
     )
     assert result[2] == ContestSummary(
-        id="1949", name="Codeforces Global Round 26", display_name="Global Round 26"
+        id="1949",
+        name="Codeforces Global Round 26",
+        display_name="Codeforces Global Round 26",
     )