diff --git a/README.md b/README.md
index d576a31..91bf121 100644
--- a/README.md
+++ b/README.md
@@ -46,11 +46,12 @@ A decentralized, Nostr-based git server that enables git repository hosting and
 - **Input Validation**: Validates commit messages, author names, emails, and file paths
 - **File Size Limits**: 500 MB maximum per file (allows for images and demo videos)
 - **Ownership Verification**: Verifies repository ownership via self-transfer events or verification files
-- **Commit Signing**: Sign commits using Nostr private keys (nsec or hex format)
-  - Supports both bech32 (nsec) and hex format keys
+- **Commit Signing**: Sign commits using Nostr private keys
   - Signatures embedded in commit messages as trailers
-  - Server-side signing via `NOSTRGIT_SECRET_KEY` environment variable
-  - Client-side signing via optional `nsecKey` parameter in API requests
+  - **Web UI**: Uses NIP-07 browser extension (secure, keys never leave browser)
+  - **Git Operations**: Uses NIP-98 HTTP authentication (ephemeral signed events)
+  - **Server-side**: Optional `NOSTRGIT_SECRET_KEY` environment variable for automated signing
+  - ⚠️ **Security Note**: Never send private keys (nsec) in API requests. Use NIP-07 for web UI or NIP-98 for git operations.
 
 ## Nostr Event Kinds Used
 
diff --git a/src/lib/services/git/commit-signer.ts b/src/lib/services/git/commit-signer.ts
index 06b7a0b..c298973 100644
--- a/src/lib/services/git/commit-signer.ts
+++ b/src/lib/services/git/commit-signer.ts
@@ -135,17 +135,20 @@ export function createCommitSignatureEvent(
  * by embedding them in the commit message or as a trailer
  * 
  * Supports multiple signing methods:
- * - NIP-07: Browser extension signing (client-side)
+ * - NIP-07: Browser extension signing (client-side, secure - keys never leave browser)
  * - NIP-98: Use HTTP auth event as signature (server-side, for git operations)
- * - nsec/hex: Direct key signing (server-side, when key is available)
+ * - nsec/hex: Direct key signing (server-side ONLY, via environment variables)
+ * 
+ * ⚠️ SECURITY WARNING: nsecKey should NEVER be sent from client requests.
+ * It should only be used server-side via environment variables (e.g., NOSTRGIT_SECRET_KEY).
  * 
  * @param commitMessage - The commit message to sign
  * @param authorName - Author name
  * @param authorEmail - Author email
  * @param options - Signing options
- * @param options.useNIP07 - Use NIP-07 browser extension (client-side only)
+ * @param options.useNIP07 - Use NIP-07 browser extension (client-side only, secure)
  * @param options.nip98Event - Use NIP-98 auth event as signature (server-side)
- * @param options.nsecKey - Use direct nsec/hex key (server-side)
+ * @param options.nsecKey - Use direct nsec/hex key (server-side ONLY, via env vars - NOT for client requests)
  * @param options.timestamp - Optional timestamp (defaults to now)
  * @returns Signed commit message and signature event
  */
diff --git a/src/lib/services/git/file-manager.ts b/src/lib/services/git/file-manager.ts
index 8a4c516..3e7a708 100644
--- a/src/lib/services/git/file-manager.ts
+++ b/src/lib/services/git/file-manager.ts
@@ -276,9 +276,9 @@ export class FileManager {
   /**
    * Write file and commit changes
    * @param signingOptions - Optional commit signing options:
-   *   - useNIP07: Use NIP-07 browser extension (client-side only)
+   *   - useNIP07: Use NIP-07 browser extension (client-side, secure - keys never leave browser)
    *   - nip98Event: Use NIP-98 auth event as signature (server-side, for git operations)
-   *   - nsecKey: Use direct nsec/hex key (server-side)
+   *   - nsecKey: Use direct nsec/hex key (server-side ONLY, via environment variables - NOT for client requests)
    */
   async writeFile(
     npub: string,
diff --git a/src/routes/api/repos/[npub]/[repo]/file/+server.ts b/src/routes/api/repos/[npub]/[repo]/file/+server.ts
index 292900f..5d01f61 100644
--- a/src/routes/api/repos/[npub]/[repo]/file/+server.ts
+++ b/src/routes/api/repos/[npub]/[repo]/file/+server.ts
@@ -121,6 +121,9 @@ export const POST: RequestHandler = async ({ params, url, request }: { params: {
     }
 
     // Prepare signing options
+    // NOTE: nsecKey is intentionally NOT supported from client requests for security reasons.
+    // Clients should use NIP-07 (browser extension) or NIP-98 (HTTP auth) instead.
+    // nsecKey is only for server-side use via environment variables.
     const signingOptions: {
       useNIP07?: boolean;
       nip98Event?: any;
@@ -131,9 +134,9 @@ export const POST: RequestHandler = async ({ params, url, request }: { params: {
       signingOptions.useNIP07 = true;
     } else if (nip98Event) {
       signingOptions.nip98Event = nip98Event;
-    } else if (nsecKey) {
-      signingOptions.nsecKey = nsecKey;
     }
+    // Explicitly ignore nsecKey from client requests - it's a security risk
+    // Server-side signing should use NOSTRGIT_SECRET_KEY environment variable instead
 
     if (action === 'delete') {
       await fileManager.deleteFile(