diff --git a/src/services/cache/cacheFile.ts b/src/services/cache/cacheFile.ts
index 046449546..909e7dbb5 100644
--- a/src/services/cache/cacheFile.ts
+++ b/src/services/cache/cacheFile.ts
@@ -151,10 +151,10 @@ class CacheFile {
         return true;
     }
 
-    addFileDep({filename, content}: {filename: string; content: string}) {
-        const contentHash = CacheService.getHash(content);
+    addFileDep({filename, content}: {filename: string; content: string | Uint8Array}) {
+        if (this.data.fileDeps[filename]) return;
 
-        this.data.fileDeps[filename] = contentHash;
+        this.data.fileDeps[filename] = CacheService.getHash(content);
     }
 
     addFileExists({filename, state}: {filename: string; state: boolean}) {
diff --git a/src/utils/pluginEnvApi.ts b/src/utils/pluginEnvApi.ts
index a5d271d42..692e32dab 100644
--- a/src/utils/pluginEnvApi.ts
+++ b/src/utils/pluginEnvApi.ts
@@ -26,11 +26,15 @@ class PluginEnvApi {
         return new PluginEnvApi(props);
     }
 
-    readonly root: string;
-    readonly distRoot: string;
-    cacheFile: CacheFile | undefined;
+    public readonly root: string;
+    public readonly distRoot: string;
+    public readonly cacheFile: CacheFile | undefined;
 
-    private asyncActionQueue: AsyncAction[] = [];
+    private readonly fileExistsCache = new Map<string, boolean>();
+    private readonly readFileCache = new Map<string, string | Uint8Array>();
+    private readonly mkdirCache = new Set();
+
+    private readonly asyncActionQueue: AsyncAction[] = [];
 
     constructor({root, distRoot, cacheFile}: PluginEnvApiProps) {
         this.root = root;
@@ -45,7 +49,7 @@ class PluginEnvApi {
         const fullFrom = path.join(this.root, from);
         const fullTo = path.join(this.distRoot, to);
 
-        fs.mkdirSync(path.dirname(fullTo), {recursive: true});
+        this.cacheMkdir(path.dirname(fullTo));
         fs.copyFileSync(fullFrom, fullTo);
         if (this.cacheFile) {
             this.cacheFile.addCopyFile({from, to});
@@ -59,11 +63,11 @@ class PluginEnvApi {
         this.asyncActionQueue.push({type: AsyncActionType.Copy, from, to});
     }
 
-    readFile<T extends BufferEncoding>(rawTarget: string, encoding: T) {
+    readFile<T extends BufferEncoding>(rawTarget: string, encoding: T | null = null) {
         const target = safeRelativePath(rawTarget);
         const fullTarget = path.join(this.root, target);
 
-        const result = fs.readFileSync(fullTarget, encoding);
+        const result = this.cacheReadFileSync(fullTarget, encoding);
         if (this.cacheFile) {
             this.cacheFile.addFileDep({filename: target, content: result});
         }
@@ -74,7 +78,7 @@ class PluginEnvApi {
         const target = safeRelativePath(rawTarget);
         const fullTarget = path.join(this.root, target);
 
-        const result = fs.existsSync(fullTarget);
+        const result = this.cacheExistsSync(fullTarget);
         if (this.cacheFile) {
             this.cacheFile.addFileExists({filename: target, state: result});
         }
@@ -85,7 +89,7 @@ class PluginEnvApi {
         const to = safeRelativePath(rawTo);
         const fullTo = path.join(this.distRoot, to);
 
-        fs.mkdirSync(path.dirname(fullTo), {recursive: true});
+        this.cacheMkdir(path.dirname(fullTo));
         fs.writeFileSync(fullTo, data);
         if (this.cacheFile) {
             this.cacheFile.addWriteFile(to, data);
@@ -118,7 +122,7 @@ class PluginEnvApi {
                     const fullFrom = path.join(this.root, from);
                     const fullTo = path.join(this.distRoot, to);
 
-                    fs.mkdirSync(path.dirname(fullTo), {recursive: true});
+                    this.cacheMkdir(path.dirname(fullTo));
                     fs.copyFileSync(fullFrom, fullTo);
                     if (this.cacheFile) {
                         this.cacheFile.addCopyFile({from, to});
@@ -129,7 +133,7 @@ class PluginEnvApi {
                     const {to, data} = action;
                     const fullTo = path.join(this.distRoot, to);
 
-                    fs.mkdirSync(path.dirname(fullTo), {recursive: true});
+                    this.cacheMkdir(path.dirname(fullTo));
                     fs.writeFileSync(fullTo, data);
                     if (this.cacheFile) {
                         this.cacheFile.addWriteFile(to, data);
@@ -150,7 +154,7 @@ class PluginEnvApi {
                     const fullFrom = path.join(this.root, from);
                     const fullTo = path.join(this.distRoot, to);
 
-                    await fs.promises.mkdir(path.dirname(fullTo), {recursive: true});
+                    await this.cacheMkdirAsync(path.dirname(fullTo));
                     await fs.promises.copyFile(fullFrom, fullTo);
                     if (this.cacheFile) {
                         this.cacheFile.addCopyFile({from, to});
@@ -161,7 +165,7 @@ class PluginEnvApi {
                     const {to, data} = action;
                     const fullTo = path.join(this.distRoot, to);
 
-                    await fs.promises.mkdir(path.dirname(fullTo), {recursive: true});
+                    await this.cacheMkdirAsync(path.dirname(fullTo));
                     await fs.promises.writeFile(fullTo, data);
                     if (this.cacheFile) {
                         this.cacheFile.addWriteFile(to, data);
@@ -171,6 +175,43 @@ class PluginEnvApi {
             }
         }));
     }
+
+    private cacheMkdir(path: string) {
+        const {mkdirCache} = this;
+        if (!mkdirCache.has(path)) {
+            fs.mkdirSync(path, {recursive: true});
+            mkdirCache.add(path);
+        }
+    }
+
+    private async cacheMkdirAsync(path: string) {
+        const {mkdirCache} = this;
+        if (!mkdirCache.has(path)) {
+            await fs.promises.mkdir(path, {recursive: true});
+            mkdirCache.add(path);
+        }
+    }
+
+    private cacheReadFileSync(filename: string, encoding: BufferEncoding | null = null) {
+        const {readFileCache} = this;
+        const key = `${filename}_${encoding}`;
+        let result = readFileCache.get(key);
+        if (result === undefined) {
+            result = fs.readFileSync(filename, encoding);
+            readFileCache.set(key, result);
+        }
+        return result;
+    }
+
+    private cacheExistsSync(filename: string) {
+        const {fileExistsCache} = this;
+        let result = fileExistsCache.get(filename);
+        if (result === undefined) {
+            result = fs.existsSync(filename);
+            fileExistsCache.set(filename, result);
+        }
+        return result;
+    }
 }
 
 export default PluginEnvApi;