diff --git a/types/is-deflate/.npmignore b/types/is-deflate/.npmignore
new file mode 100644
index 00000000000000..93e307400a5456
--- /dev/null
+++ b/types/is-deflate/.npmignore
@@ -0,0 +1,5 @@
+*
+!**/*.d.ts
+!**/*.d.cts
+!**/*.d.mts
+!**/*.d.*.ts
diff --git a/types/is-deflate/index.d.ts b/types/is-deflate/index.d.ts
new file mode 100644
index 00000000000000..96e08a2045467c
--- /dev/null
+++ b/types/is-deflate/index.d.ts
@@ -0,0 +1,3 @@
+export = is_deflate;
+
+declare function is_deflate(buf: Buffer | Uint8Array): boolean;
diff --git a/types/is-deflate/is-deflate-tests.ts b/types/is-deflate/is-deflate-tests.ts
new file mode 100644
index 00000000000000..44709609bfcc90
--- /dev/null
+++ b/types/is-deflate/is-deflate-tests.ts
@@ -0,0 +1,3 @@
+/// <reference types="node" />
+import isDeflate from "is-deflate";
+isDeflate(Buffer.from("blah blah"));
diff --git a/types/is-deflate/package.json b/types/is-deflate/package.json
new file mode 100644
index 00000000000000..6e6df2483eb856
--- /dev/null
+++ b/types/is-deflate/package.json
@@ -0,0 +1,18 @@
+{
+    "private": true,
+    "name": "@types/is-deflate",
+    "version": "1.0.9999",
+    "projects": [
+        "https://github.com/watson/is-deflate#readme"
+    ],
+    "devDependencies": {
+        "@types/is-deflate": "workspace:.",
+        "@types/node": "*"
+    },
+    "owners": [
+        {
+            "name": "Matt Cowley",
+            "githubUsername": "MattIPv4"
+        }
+    ]
+}
diff --git a/types/is-deflate/tsconfig.json b/types/is-deflate/tsconfig.json
new file mode 100644
index 00000000000000..f32666113fdf46
--- /dev/null
+++ b/types/is-deflate/tsconfig.json
@@ -0,0 +1,19 @@
+{
+    "compilerOptions": {
+        "module": "node16",
+        "lib": [
+            "es6"
+        ],
+        "noImplicitAny": true,
+        "noImplicitThis": true,
+        "strictFunctionTypes": true,
+        "strictNullChecks": true,
+        "types": [],
+        "noEmit": true,
+        "forceConsistentCasingInFileNames": true
+    },
+    "files": [
+        "index.d.ts",
+        "is-deflate-tests.ts"
+    ]
+}
diff --git a/types/node/node-tests/tls.ts b/types/node/node-tests/tls.ts
index 84bfa124392eb1..5b72a0eabdbe0b 100644
--- a/types/node/node-tests/tls.ts
+++ b/types/node/node-tests/tls.ts
@@ -314,6 +314,33 @@ import {
     const r00ts: readonly string[] = rootCertificates;
 }
 
+// Certificate DN fields are optional and can be string or string[] (multi-valued)
+{
+    const tlsSocket = connect({});
+    const peerCert = tlsSocket.getPeerCertificate();
+    const subject = peerCert.subject;
+
+    // Fields are optional and may be string or string[]
+    const cn: string | string[] | undefined = subject.CN;
+    const ou: string | string[] | undefined = subject.OU;
+    const o: string | string[] | undefined = subject.O;
+
+    // Type narrowing with Array.isArray
+    if (Array.isArray(subject.OU)) {
+        const ous: string[] = subject.OU;
+    } else {
+        const ou: string | undefined = subject.OU;
+    }
+
+    // Arbitrary DN attributes via index signature
+    const email: string | string[] | undefined = subject["emailAddress"];
+    const dc: string | string[] | undefined = subject["DC"];
+
+    // Issuer has the same shape
+    const issuer = peerCert.issuer;
+    const issuerCN: string | string[] | undefined = issuer.CN;
+}
+
 {
     const _options: TlsOptions = {};
     const _server = new Server(_options, (socket) => {});
diff --git a/types/node/tls.d.ts b/types/node/tls.d.ts
index 5c45f93774f058..635ee3e7ddebd9 100644
--- a/types/node/tls.d.ts
+++ b/types/node/tls.d.ts
@@ -15,31 +15,31 @@ declare module "node:tls" {
     import * as stream from "stream";
     const CLIENT_RENEG_LIMIT: number;
     const CLIENT_RENEG_WINDOW: number;
-    interface Certificate {
+    interface Certificate extends NodeJS.Dict<string | string[]> {
         /**
          * Country code.
          */
-        C: string;
+        C?: string | string[];
         /**
          * Street.
          */
-        ST: string;
+        ST?: string | string[];
         /**
          * Locality.
          */
-        L: string;
+        L?: string | string[];
         /**
          * Organization.
          */
-        O: string;
+        O?: string | string[];
         /**
          * Organizational unit.
          */
-        OU: string;
+        OU?: string | string[];
         /**
          * Common name.
          */
-        CN: string;
+        CN?: string | string[];
     }
     interface PeerCertificate {
         /**
diff --git a/types/node/v20/test/tls.ts b/types/node/v20/test/tls.ts
index 7d0298cca28178..c4fc7ebc4fbdf8 100644
--- a/types/node/v20/test/tls.ts
+++ b/types/node/v20/test/tls.ts
@@ -325,6 +325,33 @@ import {
     const r00ts: readonly string[] = rootCertificates;
 }
 
+// Certificate DN fields are optional and can be string or string[] (multi-valued)
+{
+    const tlsSocket = connect({});
+    const peerCert = tlsSocket.getPeerCertificate();
+    const subject = peerCert.subject;
+
+    // Fields are optional and may be string or string[]
+    const cn: string | string[] | undefined = subject.CN;
+    const ou: string | string[] | undefined = subject.OU;
+    const o: string | string[] | undefined = subject.O;
+
+    // Type narrowing with Array.isArray
+    if (Array.isArray(subject.OU)) {
+        const ous: string[] = subject.OU;
+    } else {
+        const ou: string | undefined = subject.OU;
+    }
+
+    // Arbitrary DN attributes via index signature
+    const email: string | string[] | undefined = subject["emailAddress"];
+    const dc: string | string[] | undefined = subject["DC"];
+
+    // Issuer has the same shape
+    const issuer = peerCert.issuer;
+    const issuerCN: string | string[] | undefined = issuer.CN;
+}
+
 {
     const _options: TlsOptions = {};
     const _server = new Server(_options, (socket) => {});
diff --git a/types/node/v20/tls.d.ts b/types/node/v20/tls.d.ts
index 0b819a1779e450..7ecc2331f2f8a2 100644
--- a/types/node/v20/tls.d.ts
+++ b/types/node/v20/tls.d.ts
@@ -15,31 +15,31 @@ declare module "tls" {
     import * as stream from "stream";
     const CLIENT_RENEG_LIMIT: number;
     const CLIENT_RENEG_WINDOW: number;
-    interface Certificate {
+    interface Certificate extends NodeJS.Dict<string | string[]> {
         /**
          * Country code.
          */
-        C: string;
+        C?: string | string[];
         /**
          * Street.
          */
-        ST: string;
+        ST?: string | string[];
         /**
          * Locality.
          */
-        L: string;
+        L?: string | string[];
         /**
          * Organization.
          */
-        O: string;
+        O?: string | string[];
         /**
          * Organizational unit.
          */
-        OU: string;
+        OU?: string | string[];
         /**
          * Common name.
          */
-        CN: string;
+        CN?: string | string[];
     }
     interface PeerCertificate {
         /**
diff --git a/types/node/v22/test/tls.ts b/types/node/v22/test/tls.ts
index 29559361ad00e7..e587ab13f7ee42 100644
--- a/types/node/v22/test/tls.ts
+++ b/types/node/v22/test/tls.ts
@@ -329,6 +329,33 @@ import {
     const r00ts: readonly string[] = rootCertificates;
 }
 
+// Certificate DN fields are optional and can be string or string[] (multi-valued)
+{
+    const tlsSocket = connect({});
+    const peerCert = tlsSocket.getPeerCertificate();
+    const subject = peerCert.subject;
+
+    // Fields are optional and may be string or string[]
+    const cn: string | string[] | undefined = subject.CN;
+    const ou: string | string[] | undefined = subject.OU;
+    const o: string | string[] | undefined = subject.O;
+
+    // Type narrowing with Array.isArray
+    if (Array.isArray(subject.OU)) {
+        const ous: string[] = subject.OU;
+    } else {
+        const ou: string | undefined = subject.OU;
+    }
+
+    // Arbitrary DN attributes via index signature
+    const email: string | string[] | undefined = subject["emailAddress"];
+    const dc: string | string[] | undefined = subject["DC"];
+
+    // Issuer has the same shape
+    const issuer = peerCert.issuer;
+    const issuerCN: string | string[] | undefined = issuer.CN;
+}
+
 {
     const _options: TlsOptions = {};
     const _server = new Server(_options, (socket) => {});
diff --git a/types/node/v22/tls.d.ts b/types/node/v22/tls.d.ts
index 84dc89f3b14e15..51770320bb5ee6 100644
--- a/types/node/v22/tls.d.ts
+++ b/types/node/v22/tls.d.ts
@@ -15,31 +15,31 @@ declare module "tls" {
     import * as stream from "stream";
     const CLIENT_RENEG_LIMIT: number;
     const CLIENT_RENEG_WINDOW: number;
-    interface Certificate {
+    interface Certificate extends NodeJS.Dict<string | string[]> {
         /**
          * Country code.
          */
-        C: string;
+        C?: string | string[];
         /**
          * Street.
          */
-        ST: string;
+        ST?: string | string[];
         /**
          * Locality.
          */
-        L: string;
+        L?: string | string[];
         /**
          * Organization.
          */
-        O: string;
+        O?: string | string[];
         /**
          * Organizational unit.
          */
-        OU: string;
+        OU?: string | string[];
         /**
          * Common name.
          */
-        CN: string;
+        CN?: string | string[];
     }
     interface PeerCertificate {
         /**
diff --git a/types/node/v24/test/tls.ts b/types/node/v24/test/tls.ts
index 29559361ad00e7..e587ab13f7ee42 100644
--- a/types/node/v24/test/tls.ts
+++ b/types/node/v24/test/tls.ts
@@ -329,6 +329,33 @@ import {
     const r00ts: readonly string[] = rootCertificates;
 }
 
+// Certificate DN fields are optional and can be string or string[] (multi-valued)
+{
+    const tlsSocket = connect({});
+    const peerCert = tlsSocket.getPeerCertificate();
+    const subject = peerCert.subject;
+
+    // Fields are optional and may be string or string[]
+    const cn: string | string[] | undefined = subject.CN;
+    const ou: string | string[] | undefined = subject.OU;
+    const o: string | string[] | undefined = subject.O;
+
+    // Type narrowing with Array.isArray
+    if (Array.isArray(subject.OU)) {
+        const ous: string[] = subject.OU;
+    } else {
+        const ou: string | undefined = subject.OU;
+    }
+
+    // Arbitrary DN attributes via index signature
+    const email: string | string[] | undefined = subject["emailAddress"];
+    const dc: string | string[] | undefined = subject["DC"];
+
+    // Issuer has the same shape
+    const issuer = peerCert.issuer;
+    const issuerCN: string | string[] | undefined = issuer.CN;
+}
+
 {
     const _options: TlsOptions = {};
     const _server = new Server(_options, (socket) => {});
diff --git a/types/node/v24/tls.d.ts b/types/node/v24/tls.d.ts
index 1e51dabf37afee..db044ac01c4d72 100644
--- a/types/node/v24/tls.d.ts
+++ b/types/node/v24/tls.d.ts
@@ -15,31 +15,31 @@ declare module "tls" {
     import * as stream from "stream";
     const CLIENT_RENEG_LIMIT: number;
     const CLIENT_RENEG_WINDOW: number;
-    interface Certificate {
+    interface Certificate extends NodeJS.Dict<string | string[]> {
         /**
          * Country code.
          */
-        C: string;
+        C?: string | string[];
         /**
          * Street.
          */
-        ST: string;
+        ST?: string | string[];
         /**
          * Locality.
          */
-        L: string;
+        L?: string | string[];
         /**
          * Organization.
          */
-        O: string;
+        O?: string | string[];
         /**
          * Organizational unit.
          */
-        OU: string;
+        OU?: string | string[];
         /**
          * Common name.
          */
-        CN: string;
+        CN?: string | string[];
     }
     interface PeerCertificate {
         /**