diff --git a/lua/cp/config.lua b/lua/cp/config.lua
index 8b1a482..6d00698 100644
--- a/lua/cp/config.lua
+++ b/lua/cp/config.lua
@@ -126,11 +126,14 @@ function M.setup(user_config)
     end
 
     if user_config.scrapers then
-      for _, contest_name in ipairs(user_config.scrapers) do
-        if not vim.tbl_contains(constants.PLATFORMS, contest_name) then
+      for _, platform_name in ipairs(user_config.scrapers) do
+        if type(platform_name) ~= 'string' then
+          error(('Invalid scraper value type. Expected string, got %s'):format(type(platform_name)))
+        end
+        if not vim.tbl_contains(constants.PLATFORMS, platform_name) then
           error(
-            ("Invalid contest '%s' in scrapers config. Valid contests: %s"):format(
-              contest_name,
+            ("Invalid platform '%s' in scrapers config. Valid platforms: %s"):format(
+              platform_name,
               table.concat(constants.PLATFORMS, ', ')
             )
           )
diff --git a/lua/cp/snippets.lua b/lua/cp/snippets.lua
index 43feaf5..b7b03ed 100644
--- a/lua/cp/snippets.lua
+++ b/lua/cp/snippets.lua
@@ -101,7 +101,7 @@ if __name__ == "__main__":
   }
 
   local user_overrides = {}
-  for _, snippet in ipairs(config.snippets) do
+  for _, snippet in ipairs(config.snippets or {}) do
     user_overrides[snippet.trigger] = snippet
   end
 
diff --git a/spec/config_spec.lua b/spec/config_spec.lua
index 97b504c..3b94ddf 100644
--- a/spec/config_spec.lua
+++ b/spec/config_spec.lua
@@ -46,7 +46,7 @@ describe('cp.config', function()
 
     it('validates scraper platforms', function()
       local invalid_config = {
-        scrapers = { invalid_platform = true },
+        scrapers = { 'invalid_platform' },
       }
 
       assert.has_error(function()
@@ -54,9 +54,9 @@ describe('cp.config', function()
       end)
     end)
 
-    it('validates scraper values are booleans', function()
+    it('validates scraper values are strings', function()
       local invalid_config = {
-        scrapers = { atcoder = 'not_boolean' },
+        scrapers = { 123 },
       }
 
       assert.has_error(function()
diff --git a/spec/health_spec.lua b/spec/health_spec.lua
index 3bf774e..80c55f0 100644
--- a/spec/health_spec.lua
+++ b/spec/health_spec.lua
@@ -2,6 +2,9 @@ describe('cp.health', function()
   local health
 
   before_each(function()
+    local original_gsub = string.gsub
+    string.gsub = original_gsub
+
     vim.fn = vim.tbl_extend('force', vim.fn, {
       executable = function()
         return 1
diff --git a/spec/integration_spec.lua b/spec/integration_spec.lua
index 9ab1781..bb3ac31 100644
--- a/spec/integration_spec.lua
+++ b/spec/integration_spec.lua
@@ -80,6 +80,7 @@ describe('cp integration', function()
           default_language = 'cpp',
           timeout_ms = 2000,
           cpp = {
+            extension = 'cpp',
             compile = { 'g++', '{source}', '-o', '{binary}' },
             run = { '{binary}' },
           },
@@ -201,7 +202,19 @@ describe('cp integration', function()
 
     it('handles scraper communication properly', function()
       vim.system = function(cmd)
-        if cmd[1] == 'uv' and vim.tbl_contains(cmd, 'metadata') then
+        if cmd[1] == 'ping' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif cmd[1] == 'uv' and cmd[2] == 'sync' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif cmd[1] == 'uv' and vim.tbl_contains(cmd, 'metadata') then
           return {
             wait = function()
               return { code = 1, stderr = 'network error' }
@@ -232,7 +245,19 @@ describe('cp integration', function()
 
     it('processes scraper output correctly', function()
       vim.system = function(cmd)
-        if vim.tbl_contains(cmd, 'metadata') then
+        if cmd[1] == 'ping' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif cmd[1] == 'uv' and cmd[2] == 'sync' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif vim.tbl_contains(cmd, 'metadata') then
           return {
             wait = function()
               return {
@@ -339,7 +364,19 @@ describe('cp integration', function()
 
     it('recovers from interrupted operations', function()
       vim.system = function(cmd)
-        if vim.tbl_contains(cmd, 'metadata') then
+        if cmd[1] == 'ping' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif cmd[1] == 'uv' and cmd[2] == 'sync' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif vim.tbl_contains(cmd, 'metadata') then
           return {
             wait = function()
               return { code = 1, stderr = 'interrupted' }
@@ -394,7 +431,19 @@ describe('cp integration', function()
 
     it('maintains system stability on errors', function()
       vim.system = function(cmd)
-        if vim.tbl_contains(cmd, 'metadata') then
+        if cmd[1] == 'ping' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif cmd[1] == 'uv' and cmd[2] == 'sync' then
+          return {
+            wait = function()
+              return { code = 0 }
+            end,
+          }
+        elseif vim.tbl_contains(cmd, 'metadata') then
           return {
             wait = function()
               return { code = 1, stderr = 'scraper failed' }
diff --git a/spec/test_panel_spec.lua b/spec/test_panel_spec.lua
index d0deb17..802e44d 100644
--- a/spec/test_panel_spec.lua
+++ b/spec/test_panel_spec.lua
@@ -154,7 +154,11 @@ describe('cp test panel', function()
       },
     })
 
-    vim.cmd('silent! %bwipeout!')
+    vim.cmd = function(cmd_str)
+      if cmd_str:match('silent! %%bwipeout!') then
+        return
+      end
+    end
   end)
 
   after_each(function()
@@ -163,7 +167,11 @@ describe('cp test panel', function()
     package.loaded['cp.test'] = nil
     package.loaded['cp.problem'] = nil
     package.loaded['cp.execute'] = nil
-    vim.cmd('silent! %bwipeout!')
+    vim.cmd = function(cmd_str)
+      if cmd_str:match('silent! %%bwipeout!') then
+        return
+      end
+    end
   end)
 
   describe('panel creation', function()