diff --git a/src/annotations/annotations.ts b/src/annotations/annotations.ts
index b4041e0..161153a 100644
--- a/src/annotations/annotations.ts
+++ b/src/annotations/annotations.ts
@@ -77,7 +77,7 @@ export class Annotations {
         hunkLine?: GitDiffHunkLine
     ): Promise<MarkdownString | undefined> {
         const documentRef = uri.sha;
-        if (commit instanceof GitBlameCommit) {
+        if (GitBlameCommit.is(commit)) {
             // TODO: Figure out how to optimize this
             let ref;
             if (commit.isUncommitted) {
diff --git a/src/commands/common.ts b/src/commands/common.ts
index d54690c..1001ea1 100644
--- a/src/commands/common.ts
+++ b/src/commands/common.ts
@@ -239,7 +239,7 @@ export function isCommandViewContextWithBranch(
 ): context is CommandViewItemContext & { node: ViewNode & { branch: GitBranch } } {
     if (context.type !== 'viewItem') return false;
 
-    return (context.node as ViewNode & { branch: GitBranch }).branch instanceof GitBranch;
+    return GitBranch.is((context.node as ViewNode & { branch: GitBranch }).branch);
 }
 
 export function isCommandViewContextWithCommit<T extends GitCommit>(
@@ -247,7 +247,7 @@ export function isCommandViewContextWithCommit<T extends GitCommit>(
 ): context is CommandViewItemContext & { node: ViewNode & { commit: T } } {
     if (context.type !== 'viewItem') return false;
 
-    return (context.node as ViewNode & { commit: GitCommit }).commit instanceof GitCommit;
+    return GitCommit.is((context.node as ViewNode & { commit: GitCommit }).commit);
 }
 
 export function isCommandViewContextWithContributor(
@@ -255,7 +255,7 @@ export function isCommandViewContextWithContributor(
 ): context is CommandViewItemContext & { node: ViewNode & { contributor: GitContributor } } {
     if (context.type !== 'viewItem') return false;
 
-    return (context.node as ViewNode & { contributor: GitContributor }).contributor instanceof GitContributor;
+    return GitContributor.is((context.node as ViewNode & { contributor: GitContributor }).contributor);
 }
 
 export function isCommandViewContextWithFile(
@@ -275,7 +275,7 @@ export function isCommandViewContextWithFileCommit(
     const node = context.node as ViewNode & { commit: GitCommit; file: GitFile; repoPath: string };
     return (
         node.file !== undefined &&
-        node.commit instanceof GitCommit &&
+        GitCommit.is(node.commit) &&
         (node.file.repoPath !== undefined || node.repoPath !== undefined)
     );
 }
@@ -307,7 +307,7 @@ export function isCommandViewContextWithRemote(
 ): context is CommandViewItemContext & { node: ViewNode & { remote: GitRemote } } {
     if (context.type !== 'viewItem') return false;
 
-    return (context.node as ViewNode & { remote: GitRemote }).remote instanceof GitRemote;
+    return GitRemote.is((context.node as ViewNode & { remote: GitRemote }).remote);
 }
 
 export function isCommandViewContextWithRepo(
@@ -548,7 +548,7 @@ export async function openEditor(
 ): Promise<TextEditor | undefined> {
     const { rethrow, ...opts } = options;
     try {
-        if (uri instanceof GitUri) {
+        if (GitUri.is(uri)) {
             uri = uri.documentUri();
         }
 
diff --git a/src/commands/diffWith.ts b/src/commands/diffWith.ts
index a4e1e43..3198c24 100644
--- a/src/commands/diffWith.ts
+++ b/src/commands/diffWith.ts
@@ -29,7 +29,7 @@ export class DiffWithCommand extends ActiveEditorCommand {
     static getMarkdownCommandArgs(commit: GitCommit, line?: number): string;
     static getMarkdownCommandArgs(argsOrCommit: DiffWithCommandArgs | GitCommit, line?: number): string {
         let args: DiffWithCommandArgs | GitCommit;
-        if (argsOrCommit instanceof GitCommit) {
+        if (GitCommit.is(argsOrCommit)) {
             const commit = argsOrCommit;
 
             if (commit.isUncommitted) {
diff --git a/src/commands/diffWithRevision.ts b/src/commands/diffWithRevision.ts
index ae04d94..58b4600 100644
--- a/src/commands/diffWithRevision.ts
+++ b/src/commands/diffWithRevision.ts
@@ -86,12 +86,7 @@ export class DiffWithRevisionCommand extends ActiveEditorCommand {
             }
 
             commandArgs = { ...args };
-            const icon =
-                args.reference instanceof GitTag
-                    ? '$(tag) '
-                    : args.reference instanceof GitBranch
-                    ? '$(git-branch) '
-                    : '';
+            const icon = GitTag.is(args.reference) ? '$(tag) ' : GitBranch.is(args.reference) ? '$(git-branch) ' : '';
             const currentCommand = new CommandQuickPickItem(
                 {
                     label: `go back ${GlyphChars.ArrowBack}`,
diff --git a/src/commands/openFileRevision.ts b/src/commands/openFileRevision.ts
index f338bc1..0ab6217 100644
--- a/src/commands/openFileRevision.ts
+++ b/src/commands/openFileRevision.ts
@@ -117,12 +117,11 @@ export class OpenFileRevisionCommand extends ActiveEditorCommand {
                 }
 
                 commandArgs = { ...args };
-                const icon =
-                    args.reference instanceof GitTag
-                        ? '$(tag) '
-                        : args.reference instanceof GitBranch
-                        ? '$(git-branch) '
-                        : '';
+                const icon = GitTag.is(args.reference)
+                    ? '$(tag) '
+                    : GitBranch.is(args.reference)
+                    ? '$(git-branch) '
+                    : '';
                 const currentCommand = new CommandQuickPickItem(
                     {
                         label: `go back ${GlyphChars.ArrowBack}`,
diff --git a/src/commands/openWorkingFile.ts b/src/commands/openWorkingFile.ts
index cf72c69..8359c08 100644
--- a/src/commands/openWorkingFile.ts
+++ b/src/commands/openWorkingFile.ts
@@ -36,7 +36,7 @@ export class OpenWorkingFileCommand extends ActiveEditorCommand {
             }
 
             args.uri = await GitUri.fromUri(uri);
-            if (args.uri instanceof GitUri && args.uri.sha) {
+            if (GitUri.is(args.uri) && args.uri.sha) {
                 const workingUri = await Container.git.getWorkingUri(args.uri.repoPath!, args.uri);
                 if (workingUri === undefined) {
                     return window.showWarningMessage(
diff --git a/src/commands/showQuickFileHistory.ts b/src/commands/showQuickFileHistory.ts
index 55515a3..155e85b 100644
--- a/src/commands/showQuickFileHistory.ts
+++ b/src/commands/showQuickFileHistory.ts
@@ -111,12 +111,7 @@ export class ShowQuickFileHistoryCommand extends ActiveEditorCachedCommand {
                 }
             }
 
-            const icon =
-                args.reference instanceof GitTag
-                    ? '$(tag) '
-                    : args.reference instanceof GitBranch
-                    ? '$(git-branch) '
-                    : '';
+            const icon = GitTag.is(args.reference) ? '$(tag) ' : GitBranch.is(args.reference) ? '$(git-branch) ' : '';
             // Create a command to get back to where we are right now
             const currentCommand = new CommandQuickPickItem(
                 {
diff --git a/src/extension.ts b/src/extension.ts
index 30861e1..d5896ff 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -18,13 +18,13 @@ export async function activate(context: ExtensionContext) {
     setCommandContext(CommandContext.Enabled, true);
 
     Logger.configure(context, configuration.get<TraceLevel>(configuration.name('outputLevel').value), o => {
-        if (o instanceof GitUri) {
+        if (GitUri.is(o)) {
             return `GitUri(${o.toString(true)}${o.repoPath ? ` repoPath=${o.repoPath}` : ''}${
                 o.sha ? ` sha=${o.sha}` : ''
             })`;
         }
 
-        if (o instanceof GitCommit) {
+        if (GitCommit.is(o)) {
             return `GitCommit(${o.sha ? ` sha=${o.sha}` : ''}${o.repoPath ? ` repoPath=${o.repoPath}` : ''})`;
         }
 
diff --git a/src/git/formatters/commitFormatter.ts b/src/git/formatters/commitFormatter.ts
index b72942a..0b24c54 100644
--- a/src/git/formatters/commitFormatter.ts
+++ b/src/git/formatters/commitFormatter.ts
@@ -142,14 +142,14 @@ export class CommitFormatter extends Formatter<GitCommit, CommitFormatOptions> {
 
     get changes() {
         return this._padOrTruncate(
-            this._item instanceof GitLogCommit ? this._item.getFormattedDiffStatus() : emptyStr,
+            GitLogCommit.is(this._item) ? this._item.getFormattedDiffStatus() : emptyStr,
             this._options.tokenOptions.changes
         );
     }
 
     get changesShort() {
         return this._padOrTruncate(
-            this._item instanceof GitLogCommit
+            GitLogCommit.is(this._item)
                 ? this._item.getFormattedDiffStatus({ compact: true, separator: emptyStr })
                 : emptyStr,
             this._options.tokenOptions.changesShort
diff --git a/src/git/fsProvider.ts b/src/git/fsProvider.ts
index 4f727a0..40cf380 100644
--- a/src/git/fsProvider.ts
+++ b/src/git/fsProvider.ts
@@ -20,7 +20,7 @@ import { Iterables, Strings, TernarySearchTree } from '../system';
 const emptyArray = new Uint8Array(0);
 
 export function fromGitLensFSUri(uri: Uri): { path: string; ref: string; repoPath: string } {
-    const gitUri = uri instanceof GitUri ? uri : GitUri.fromRevisionUri(uri);
+    const gitUri = GitUri.is(uri) ? uri : GitUri.fromRevisionUri(uri);
     return { path: gitUri.relativePath, ref: gitUri.sha!, repoPath: gitUri.repoPath! };
 }
 
diff --git a/src/git/gitService.ts b/src/git/gitService.ts
index e3665c2..b9d7231 100644
--- a/src/git/gitService.ts
+++ b/src/git/gitService.ts
@@ -2021,7 +2021,7 @@ export class GitService implements Disposable {
         options: { ref?: string } = {}
     ): Promise<string | undefined> {
         if (filePathOrUri == null) return this.getHighlanderRepoPath();
-        if (filePathOrUri instanceof GitUri) return filePathOrUri.repoPath;
+        if (GitUri.is(filePathOrUri)) return filePathOrUri.repoPath;
 
         const cc = Logger.getCorrelationContext();
 
@@ -2153,7 +2153,7 @@ export class GitService implements Disposable {
             isVslsScheme = undefined;
         }
         else {
-            if (repoPathOrUri instanceof GitUri) {
+            if (GitUri.is(repoPathOrUri)) {
                 if (repoPathOrUri.repoPath) {
                     const repo = repositoryTree.get(repoPathOrUri.repoPath);
                     if (repo !== undefined) return repo;
diff --git a/src/git/gitUri.ts b/src/git/gitUri.ts
index e93c769..3d2b09d 100644
--- a/src/git/gitUri.ts
+++ b/src/git/gitUri.ts
@@ -36,6 +36,10 @@ interface UriEx {
 }
 
 export class GitUri extends ((Uri as any) as UriEx) {
+    static is(uri: any): uri is GitUri {
+        return uri instanceof GitUri;
+    }
+
     readonly repoPath?: string;
     readonly sha?: string;
     readonly versionedPath?: string;
@@ -176,7 +180,7 @@ export class GitUri extends ((Uri as any) as UriEx) {
     equals(uri: Uri | undefined) {
         if (!UriComparer.equals(this, uri)) return false;
 
-        return this.sha === (uri instanceof GitUri ? uri.sha : undefined);
+        return this.sha === (GitUri.is(uri) ? uri.sha : undefined);
     }
 
     getFormattedPath(options: { relativeTo?: string; separator?: string; suffix?: string } = {}): string {
@@ -259,7 +263,7 @@ export class GitUri extends ((Uri as any) as UriEx) {
         exit: uri => `returned ${Logger.toLoggable(uri)}`
     })
     static async fromUri(uri: Uri) {
-        if (uri instanceof GitUri) return uri;
+        if (GitUri.is(uri)) return uri;
 
         if (!Container.git.isTrackable(uri)) return new GitUri(uri);
 
@@ -315,7 +319,7 @@ export class GitUri extends ((Uri as any) as UriEx) {
 
         let fileName: string;
         if (fileNameOrUri instanceof Uri) {
-            if (fileNameOrUri instanceof GitUri) return fileNameOrUri.getFormattedPath(options);
+            if (GitUri.is(fileNameOrUri)) return fileNameOrUri.getFormattedPath(options);
 
             fileName = fileNameOrUri.fsPath;
         }
diff --git a/src/git/models/blameCommit.ts b/src/git/models/blameCommit.ts
index 96d9218..07ae5b7 100644
--- a/src/git/models/blameCommit.ts
+++ b/src/git/models/blameCommit.ts
@@ -2,6 +2,13 @@
 import { GitCommit, GitCommitLine, GitCommitType } from './commit';
 
 export class GitBlameCommit extends GitCommit {
+    static is(commit: any): commit is GitBlameCommit {
+        return (
+            commit instanceof GitBlameCommit
+            //|| (commit.repoPath !== undefined && commit.sha !== undefined && commit.type === GitCommitType.Blame)
+        );
+    }
+
     constructor(
         repoPath: string,
         sha: string,
diff --git a/src/git/models/branch.ts b/src/git/models/branch.ts
index ce18916..af998ee 100644
--- a/src/git/models/branch.ts
+++ b/src/git/models/branch.ts
@@ -11,6 +11,10 @@ export interface GitTrackingState {
 }
 
 export class GitBranch {
+    static is(branch: any): branch is GitBranch {
+        return branch instanceof GitBranch;
+    }
+
     readonly detached: boolean;
     readonly id: string;
     readonly tracking?: string;
diff --git a/src/git/models/commit.ts b/src/git/models/commit.ts
index 4010e5c..c889732 100644
--- a/src/git/models/commit.ts
+++ b/src/git/models/commit.ts
@@ -42,6 +42,19 @@ export const CommitFormatting = {
 };
 
 export abstract class GitCommit {
+    static is(commit: any): commit is GitCommit {
+        return (
+            commit instanceof GitCommit
+            // || (commit.repoPath !== undefined &&
+            //     commit.sha !== undefined &&
+            //     (commit.type === GitCommitType.Blame ||
+            //         commit.type === GitCommitType.Log ||
+            //         commit.type === GitCommitType.LogFile ||
+            //         commit.type === GitCommitType.Stash ||
+            //         commit.type === GitCommitType.StashFile))
+        );
+    }
+
     constructor(
         public readonly type: GitCommitType,
         public readonly repoPath: string,
diff --git a/src/git/models/contributor.ts b/src/git/models/contributor.ts
index a4710ad..91edb42 100644
--- a/src/git/models/contributor.ts
+++ b/src/git/models/contributor.ts
@@ -4,6 +4,10 @@ import { GravatarDefaultStyle } from '../../configuration';
 import { getGravatarUri } from '../../avatars';
 
 export class GitContributor {
+    static is(contributor: any): contributor is GitContributor {
+        return contributor instanceof GitContributor;
+    }
+
     constructor(
         public readonly repoPath: string,
         public readonly name: string,
diff --git a/src/git/models/logCommit.ts b/src/git/models/logCommit.ts
index a5ee6a1..ef84834 100644
--- a/src/git/models/logCommit.ts
+++ b/src/git/models/logCommit.ts
@@ -24,6 +24,15 @@ export interface GitLogCommitLine {
 }
 
 export class GitLogCommit extends GitCommit {
+    static is(commit: any): commit is GitLogCommit {
+        return (
+            commit instanceof GitLogCommit
+            // || (commit.repoPath !== undefined &&
+            //     commit.sha !== undefined &&
+            //     (commit.type === GitCommitType.Log || commit.type === GitCommitType.LogFile))
+        );
+    }
+
     nextSha?: string;
     nextFileName?: string;
 
diff --git a/src/git/models/remote.ts b/src/git/models/remote.ts
index add94b0..36a26ac 100644
--- a/src/git/models/remote.ts
+++ b/src/git/models/remote.ts
@@ -9,6 +9,10 @@ export enum GitRemoteType {
 }
 
 export class GitRemote {
+    static is(remote: any): remote is GitRemote {
+        return remote instanceof GitRemote;
+    }
+
     constructor(
         public readonly repoPath: string,
         public readonly id: string,
diff --git a/src/git/models/repository.ts b/src/git/models/repository.ts
index f1d8ef8..464d153 100644
--- a/src/git/models/repository.ts
+++ b/src/git/models/repository.ts
@@ -228,7 +228,7 @@ export class Repository implements Disposable {
     }
 
     containsUri(uri: Uri) {
-        if (uri instanceof GitUri) {
+        if (GitUri.is(uri)) {
             uri = uri.repoPath !== undefined ? GitUri.file(uri.repoPath) : uri.documentUri();
         }
 
diff --git a/src/git/models/stashCommit.ts b/src/git/models/stashCommit.ts
index cf05085..1d894e3 100644
--- a/src/git/models/stashCommit.ts
+++ b/src/git/models/stashCommit.ts
@@ -4,8 +4,13 @@ import { GitFile } from './file';
 import { GitLogCommit } from './logCommit';
 
 export class GitStashCommit extends GitLogCommit {
-    static is(commit: GitLogCommit): commit is GitStashCommit {
-        return commit.isStash;
+    static is(commit: any): commit is GitStashCommit {
+        return (
+            commit instanceof GitStashCommit
+            // || (commit.repoPath !== undefined &&
+            //     commit.sha !== undefined &&
+            //     (commit.type === GitCommitType.Stash || commit.type === GitCommitType.StashFile))
+        );
     }
 
     constructor(
diff --git a/src/git/models/tag.ts b/src/git/models/tag.ts
index 0b98f42..2b14606 100644
--- a/src/git/models/tag.ts
+++ b/src/git/models/tag.ts
@@ -2,6 +2,10 @@
 import { memoize } from '../../system';
 
 export class GitTag {
+    static is(tag: any): tag is GitTag {
+        return tag instanceof GitTag;
+    }
+
     constructor(
         public readonly repoPath: string,
         public readonly name: string,
diff --git a/src/trackers/documentTracker.ts b/src/trackers/documentTracker.ts
index 1336087..aad1162 100644
--- a/src/trackers/documentTracker.ts
+++ b/src/trackers/documentTracker.ts
@@ -236,7 +236,7 @@ export class DocumentTracker<T> implements Disposable {
 
     private async _add(documentOrId: TextDocument | Uri): Promise<TrackedDocument<T>> {
         let document;
-        if (documentOrId instanceof GitUri) {
+        if (GitUri.is(documentOrId)) {
             try {
                 document = await workspace.openTextDocument(documentOrId.documentUri({ useVersionedPath: true }));
             }
@@ -273,7 +273,7 @@ export class DocumentTracker<T> implements Disposable {
     }
 
     private async _get(documentOrId: string | TextDocument | Uri) {
-        if (documentOrId instanceof GitUri) {
+        if (GitUri.is(documentOrId)) {
             documentOrId = GitUri.toKey(documentOrId.documentUri({ useVersionedPath: true }));
         }
         else if (typeof documentOrId === 'string' || documentOrId instanceof Uri) {