diff --git a/Cargo.lock b/Cargo.lock
index 057956a7c..ce405c196 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2129,6 +2129,18 @@ dependencies = [
  "tracing-subscriber",
 ]
 
+[[package]]
+name = "gitbutler-testsupport"
+version = "0.0.0"
+dependencies = [
+ "anyhow",
+ "git2",
+ "gitbutler-core",
+ "once_cell",
+ "pretty_assertions",
+ "tempfile",
+]
+
 [[package]]
 name = "glib"
 version = "0.15.12"
diff --git a/Cargo.toml b/Cargo.toml
index e0cb5dd01..ca0a57428 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,6 +4,7 @@ members = [
     "crates/gitbutler-tauri",
     "crates/gitbutler-changeset",
     "crates/gitbutler-git",
+    "crates/gitbutler-testsupport",
 ]
 resolver = "2"
 
diff --git a/crates/gitbutler-testsupport/Cargo.toml b/crates/gitbutler-testsupport/Cargo.toml
new file mode 100644
index 000000000..f87a71bc8
--- /dev/null
+++ b/crates/gitbutler-testsupport/Cargo.toml
@@ -0,0 +1,18 @@
+[package]
+name = "gitbutler-testsupport"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[lib]
+path = "src/lib.rs"
+doctest = false
+test = false
+
+[dependencies]
+anyhow = "1.0.81"
+once_cell = "1.19"
+git2.workspace = true
+pretty_assertions = "1.4"
+tempfile = "3.10.1"
+gitbutler-core = { path = "../gitbutler-core" }
diff --git a/crates/gitbutler-testsupport/src/lib.rs b/crates/gitbutler-testsupport/src/lib.rs
new file mode 100644
index 000000000..8b663812c
--- /dev/null
+++ b/crates/gitbutler-testsupport/src/lib.rs
@@ -0,0 +1,69 @@
+pub const VAR_NO_CLEANUP: &str = "GITBUTLER_TESTS_NO_CLEANUP";
+
+mod test_project;
+pub use test_project::TestProject;
+
+mod suite;
+pub use suite::*;
+
+pub mod paths {
+    use tempfile::TempDir;
+
+    use super::temp_dir;
+
+    pub fn data_dir() -> TempDir {
+        temp_dir()
+    }
+}
+
+pub mod virtual_branches {
+    use gitbutler_core::{
+        gb_repository, project_repository,
+        virtual_branches::{self, VirtualBranchesHandle},
+    };
+
+    use crate::empty_bare_repository;
+
+    pub fn set_test_target(
+        gb_repo: &gb_repository::Repository,
+        project_repository: &project_repository::Repository,
+    ) -> anyhow::Result<()> {
+        let (remote_repo, _tmp) = empty_bare_repository();
+        let mut remote = project_repository
+            .git_repository
+            .remote(
+                "origin",
+                &remote_repo.path().to_str().unwrap().parse().unwrap(),
+            )
+            .expect("failed to add remote");
+        remote.push(&["refs/heads/master:refs/heads/master"], None)?;
+
+        virtual_branches::target::Writer::new(
+            gb_repo,
+            VirtualBranchesHandle::new(&project_repository.project().gb_dir()),
+        )?
+        .write_default(&virtual_branches::target::Target {
+            branch: "refs/remotes/origin/master".parse().unwrap(),
+            remote_url: remote_repo.path().to_str().unwrap().parse().unwrap(),
+            sha: remote_repo.head().unwrap().target().unwrap(),
+        })
+        .expect("failed to write target");
+
+        virtual_branches::integration::update_gitbutler_integration(gb_repo, project_repository)
+            .expect("failed to update integration");
+
+        Ok(())
+    }
+}
+
+pub fn init_opts() -> git2::RepositoryInitOptions {
+    let mut opts = git2::RepositoryInitOptions::new();
+    opts.initial_head("master");
+    opts
+}
+
+pub fn init_opts_bare() -> git2::RepositoryInitOptions {
+    let mut opts = init_opts();
+    opts.bare(true);
+    opts
+}
diff --git a/crates/gitbutler-testsupport/src/suite.rs b/crates/gitbutler-testsupport/src/suite.rs
new file mode 100644
index 000000000..ca9bcef59
--- /dev/null
+++ b/crates/gitbutler-testsupport/src/suite.rs
@@ -0,0 +1,232 @@
+use std::{
+    collections::HashMap,
+    fs,
+    path::{Path, PathBuf},
+};
+
+use tempfile::{tempdir, TempDir};
+
+use crate::{init_opts, init_opts_bare, VAR_NO_CLEANUP};
+
+pub struct Suite {
+    pub local_app_data: Option<TempDir>,
+    pub storage: gitbutler_core::storage::Storage,
+    pub users: gitbutler_core::users::Controller,
+    pub projects: gitbutler_core::projects::Controller,
+    pub keys: gitbutler_core::keys::Controller,
+}
+
+impl Drop for Suite {
+    fn drop(&mut self) {
+        if std::env::var_os(VAR_NO_CLEANUP).is_some() {
+            let _ = self.local_app_data.take().unwrap().into_path();
+        }
+    }
+}
+
+impl Default for Suite {
+    fn default() -> Self {
+        let local_app_data = temp_dir();
+        let storage = gitbutler_core::storage::Storage::new(&local_app_data);
+        let users = gitbutler_core::users::Controller::from_path(&local_app_data);
+        let projects = gitbutler_core::projects::Controller::from_path(&local_app_data);
+        let keys = gitbutler_core::keys::Controller::from_path(&local_app_data);
+        Self {
+            storage,
+            local_app_data: Some(local_app_data),
+            users,
+            projects,
+            keys,
+        }
+    }
+}
+
+impl Suite {
+    pub fn local_app_data(&self) -> &Path {
+        self.local_app_data.as_ref().unwrap().path()
+    }
+    pub fn sign_in(&self) -> gitbutler_core::users::User {
+        let user = gitbutler_core::users::User {
+            name: Some("test".to_string()),
+            email: "test@email.com".to_string(),
+            access_token: "token".to_string(),
+            ..Default::default()
+        };
+        self.users.set_user(&user).expect("failed to add user");
+        user
+    }
+
+    fn project(&self, fs: HashMap<PathBuf, &str>) -> (gitbutler_core::projects::Project, TempDir) {
+        let (repository, tmp) = test_repository();
+        for (path, contents) in fs {
+            if let Some(parent) = path.parent() {
+                fs::create_dir_all(repository.path().parent().unwrap().join(parent))
+                    .expect("failed to create dir");
+            }
+            fs::write(
+                repository.path().parent().unwrap().join(&path),
+                contents.as_bytes(),
+            )
+            .expect("failed to write file");
+        }
+        commit_all(&repository);
+
+        (
+            self.projects
+                .add(repository.path().parent().unwrap())
+                .expect("failed to add project"),
+            tmp,
+        )
+    }
+
+    pub fn new_case_with_files(&self, fs: HashMap<PathBuf, &str>) -> Case {
+        let (project, project_tmp) = self.project(fs);
+        Case::new(self, project, project_tmp)
+    }
+
+    pub fn new_case(&self) -> Case {
+        self.new_case_with_files(HashMap::new())
+    }
+}
+
+pub struct Case<'a> {
+    suite: &'a Suite,
+    pub project: gitbutler_core::projects::Project,
+    pub project_repository: gitbutler_core::project_repository::Repository,
+    pub gb_repository: gitbutler_core::gb_repository::Repository,
+    pub credentials: gitbutler_core::git::credentials::Helper,
+    /// The directory containing the `project_repository`
+    project_tmp: Option<TempDir>,
+}
+
+impl Drop for Case<'_> {
+    fn drop(&mut self) {
+        if let Some(tmp) = self
+            .project_tmp
+            .take()
+            .filter(|_| std::env::var_os(VAR_NO_CLEANUP).is_some())
+        {
+            let _ = tmp.into_path();
+        }
+    }
+}
+
+impl<'a> Case<'a> {
+    fn new(
+        suite: &'a Suite,
+        project: gitbutler_core::projects::Project,
+        project_tmp: TempDir,
+    ) -> Case<'a> {
+        let project_repository = gitbutler_core::project_repository::Repository::open(&project)
+            .expect("failed to create project repository");
+        let gb_repository = gitbutler_core::gb_repository::Repository::open(
+            suite.local_app_data(),
+            &project_repository,
+            None,
+        )
+        .expect("failed to open gb repository");
+        let credentials =
+            gitbutler_core::git::credentials::Helper::from_path(suite.local_app_data());
+        Case {
+            suite,
+            project,
+            gb_repository,
+            project_repository,
+            project_tmp: Some(project_tmp),
+            credentials,
+        }
+    }
+
+    pub fn refresh(mut self) -> Self {
+        let project = self
+            .suite
+            .projects
+            .get(&self.project.id)
+            .expect("failed to get project");
+        let project_repository = gitbutler_core::project_repository::Repository::open(&project)
+            .expect("failed to create project repository");
+        let user = self.suite.users.get_user().expect("failed to get user");
+        let credentials =
+            gitbutler_core::git::credentials::Helper::from_path(self.suite.local_app_data());
+        Self {
+            suite: self.suite,
+            gb_repository: gitbutler_core::gb_repository::Repository::open(
+                self.suite.local_app_data(),
+                &project_repository,
+                user.as_ref(),
+            )
+            .expect("failed to open gb repository"),
+            credentials,
+            project_repository,
+            project,
+            project_tmp: self.project_tmp.take(),
+        }
+    }
+}
+
+pub fn test_database() -> (gitbutler_core::database::Database, TempDir) {
+    let tmp = temp_dir();
+    let db = gitbutler_core::database::Database::open_in_directory(&tmp).unwrap();
+    (db, tmp)
+}
+
+pub fn temp_dir() -> TempDir {
+    tempdir().unwrap()
+}
+
+pub fn empty_bare_repository() -> (gitbutler_core::git::Repository, TempDir) {
+    let tmp = temp_dir();
+    (
+        gitbutler_core::git::Repository::init_opts(&tmp, &init_opts_bare())
+            .expect("failed to init repository"),
+        tmp,
+    )
+}
+
+pub fn test_repository() -> (gitbutler_core::git::Repository, TempDir) {
+    let tmp = temp_dir();
+    let repository = gitbutler_core::git::Repository::init_opts(&tmp, &init_opts())
+        .expect("failed to init repository");
+    let mut index = repository.index().expect("failed to get index");
+    let oid = index.write_tree().expect("failed to write tree");
+    let signature = gitbutler_core::git::Signature::now("test", "test@email.com").unwrap();
+    repository
+        .commit(
+            Some(&"refs/heads/master".parse().unwrap()),
+            &signature,
+            &signature,
+            "Initial commit",
+            &repository.find_tree(oid).expect("failed to find tree"),
+            &[],
+        )
+        .expect("failed to commit");
+    (repository, tmp)
+}
+
+pub fn commit_all(repository: &gitbutler_core::git::Repository) -> gitbutler_core::git::Oid {
+    let mut index = repository.index().expect("failed to get index");
+    index
+        .add_all(["."], git2::IndexAddOption::DEFAULT, None)
+        .expect("failed to add all");
+    index.write().expect("failed to write index");
+    let oid = index.write_tree().expect("failed to write tree");
+    let signature = gitbutler_core::git::Signature::now("test", "test@email.com").unwrap();
+    let head = repository.head().expect("failed to get head");
+    let commit_oid = repository
+        .commit(
+            Some(&head.name().unwrap()),
+            &signature,
+            &signature,
+            "some commit",
+            &repository.find_tree(oid).expect("failed to find tree"),
+            &[&repository
+                .find_commit(
+                    repository
+                        .refname_to_id("HEAD")
+                        .expect("failed to get head"),
+                )
+                .expect("failed to find commit")],
+        )
+        .expect("failed to commit");
+    commit_oid
+}
diff --git a/crates/gitbutler-testsupport/src/test_project.rs b/crates/gitbutler-testsupport/src/test_project.rs
new file mode 100644
index 000000000..d9e22f9ff
--- /dev/null
+++ b/crates/gitbutler-testsupport/src/test_project.rs
@@ -0,0 +1,346 @@
+use std::path;
+
+use gitbutler_core::git;
+use tempfile::TempDir;
+
+use crate::{init_opts, VAR_NO_CLEANUP};
+
+pub fn temp_dir() -> TempDir {
+    tempfile::tempdir().unwrap()
+}
+
+pub struct TestProject {
+    local_repository: git::Repository,
+    local_tmp: Option<TempDir>,
+    remote_repository: git::Repository,
+    remote_tmp: Option<TempDir>,
+}
+
+impl Drop for TestProject {
+    fn drop(&mut self) {
+        if std::env::var_os(VAR_NO_CLEANUP).is_some() {
+            let _ = self.local_tmp.take().unwrap().into_path();
+            let _ = self.remote_tmp.take().unwrap().into_path();
+        }
+    }
+}
+
+impl Default for TestProject {
+    fn default() -> Self {
+        let local_tmp = temp_dir();
+        let local_repository = git::Repository::init_opts(local_tmp.path(), &init_opts())
+            .expect("failed to init repository");
+        let mut index = local_repository.index().expect("failed to get index");
+        let oid = index.write_tree().expect("failed to write tree");
+        let signature = git::Signature::now("test", "test@email.com").unwrap();
+        local_repository
+            .commit(
+                Some(&"refs/heads/master".parse().unwrap()),
+                &signature,
+                &signature,
+                "Initial commit",
+                &local_repository
+                    .find_tree(oid)
+                    .expect("failed to find tree"),
+                &[],
+            )
+            .expect("failed to commit");
+
+        let remote_tmp = temp_dir();
+        let remote_repository = git::Repository::init_opts(
+            remote_tmp.path(),
+            git2::RepositoryInitOptions::new()
+                .bare(true)
+                .external_template(false),
+        )
+        .expect("failed to init repository");
+
+        {
+            let mut remote = local_repository
+                .remote(
+                    "origin",
+                    &remote_repository
+                        .path()
+                        .to_str()
+                        .expect("failed to convert path to str")
+                        .parse()
+                        .unwrap(),
+                )
+                .expect("failed to add remote");
+            remote
+                .push(&["refs/heads/master:refs/heads/master"], None)
+                .expect("failed to push");
+        }
+
+        Self {
+            local_repository,
+            local_tmp: Some(local_tmp),
+            remote_repository,
+            remote_tmp: Some(remote_tmp),
+        }
+    }
+}
+
+impl TestProject {
+    pub fn path(&self) -> &std::path::Path {
+        self.local_repository.workdir().unwrap()
+    }
+
+    pub fn push_branch(&self, branch: &git::LocalRefname) {
+        let mut origin = self.local_repository.find_remote("origin").unwrap();
+        origin.push(&[&format!("{branch}:{branch}")], None).unwrap();
+    }
+
+    pub fn push(&self) {
+        let mut origin = self.local_repository.find_remote("origin").unwrap();
+        origin
+            .push(&["refs/heads/master:refs/heads/master"], None)
+            .unwrap();
+    }
+
+    /// git add -A
+    /// git reset --hard <oid>
+    pub fn reset_hard(&self, oid: Option<git::Oid>) {
+        let mut index = self.local_repository.index().expect("failed to get index");
+        index
+            .add_all(["."], git2::IndexAddOption::DEFAULT, None)
+            .expect("failed to add all");
+        index.write().expect("failed to write index");
+
+        let head = self.local_repository.head().unwrap();
+        let commit = oid.map_or(head.peel_to_commit().unwrap(), |oid| {
+            self.local_repository.find_commit(oid).unwrap()
+        });
+
+        let head_ref = head.name().unwrap();
+        self.local_repository.find_reference(&head_ref).unwrap();
+
+        self.local_repository
+            .reset(&commit, git2::ResetType::Hard, None)
+            .unwrap();
+    }
+
+    /// fetch remote into local
+    pub fn fetch(&self) {
+        let mut remote = self.local_repository.find_remote("origin").unwrap();
+        remote
+            .fetch(&["+refs/heads/*:refs/remotes/origin/*"], None)
+            .unwrap();
+    }
+
+    pub fn rebase_and_merge(&self, branch_name: &git::Refname) {
+        let branch_name: git::Refname = match branch_name {
+            git::Refname::Local(local) => format!("refs/heads/{}", local.branch()).parse().unwrap(),
+            git::Refname::Remote(remote) => {
+                format!("refs/heads/{}", remote.branch()).parse().unwrap()
+            }
+            _ => "INVALID".parse().unwrap(), // todo
+        };
+        let branch = self.remote_repository.find_branch(&branch_name).unwrap();
+        let branch_commit = branch.peel_to_commit().unwrap();
+
+        let master_branch = {
+            let name: git::Refname = "refs/heads/master".parse().unwrap();
+            self.remote_repository.find_branch(&name).unwrap()
+        };
+        let master_branch_commit = master_branch.peel_to_commit().unwrap();
+
+        let mut rebase_options = git2::RebaseOptions::new();
+        rebase_options.quiet(true);
+        rebase_options.inmemory(true);
+
+        let mut rebase = self
+            .remote_repository
+            .rebase(
+                Some(branch_commit.id()),
+                Some(master_branch_commit.id()),
+                None,
+                Some(&mut rebase_options),
+            )
+            .unwrap();
+
+        let mut rebase_success = true;
+        let mut last_rebase_head = branch_commit.id();
+        while let Some(Ok(op)) = rebase.next() {
+            let commit = self.remote_repository.find_commit(op.id().into()).unwrap();
+            let index = rebase.inmemory_index().unwrap();
+            if index.has_conflicts() {
+                rebase_success = false;
+                break;
+            }
+
+            if let Ok(commit_id) = rebase.commit(None, &commit.committer().into(), None) {
+                last_rebase_head = commit_id.into();
+            } else {
+                rebase_success = false;
+                break;
+            };
+        }
+
+        if rebase_success {
+            self.remote_repository
+                .reference(
+                    &"refs/heads/master".parse().unwrap(),
+                    last_rebase_head,
+                    true,
+                    &format!("rebase: {}", branch_name),
+                )
+                .unwrap();
+        } else {
+            rebase.abort().unwrap();
+        }
+    }
+
+    /// works like if we'd open and merge a PR on github. does not update local.
+    pub fn merge(&self, branch_name: &git::Refname) {
+        let branch_name: git::Refname = match branch_name {
+            git::Refname::Local(local) => format!("refs/heads/{}", local.branch()).parse().unwrap(),
+            git::Refname::Remote(remote) => {
+                format!("refs/heads/{}", remote.branch()).parse().unwrap()
+            }
+            _ => "INVALID".parse().unwrap(), // todo
+        };
+        let branch = self.remote_repository.find_branch(&branch_name).unwrap();
+        let branch_commit = branch.peel_to_commit().unwrap();
+
+        let master_branch = {
+            let name: git::Refname = "refs/heads/master".parse().unwrap();
+            self.remote_repository.find_branch(&name).unwrap()
+        };
+        let master_branch_commit = master_branch.peel_to_commit().unwrap();
+
+        let merge_base = {
+            let oid = self
+                .remote_repository
+                .merge_base(branch_commit.id(), master_branch_commit.id())
+                .unwrap();
+            self.remote_repository.find_commit(oid).unwrap()
+        };
+        let merge_tree = {
+            let mut merge_index = self
+                .remote_repository
+                .merge_trees(
+                    &merge_base.tree().unwrap(),
+                    &master_branch.peel_to_tree().unwrap(),
+                    &branch.peel_to_tree().unwrap(),
+                )
+                .unwrap();
+            let oid = merge_index.write_tree_to(&self.remote_repository).unwrap();
+            self.remote_repository.find_tree(oid).unwrap()
+        };
+
+        self.remote_repository
+            .commit(
+                Some(&"refs/heads/master".parse().unwrap()),
+                &branch_commit.author(),
+                &branch_commit.committer(),
+                &format!("Merge pull request from {}", branch_name),
+                &merge_tree,
+                &[&master_branch_commit, &branch_commit],
+            )
+            .unwrap();
+    }
+
+    pub fn find_commit(&self, oid: git::Oid) -> Result<git::Commit, git::Error> {
+        self.local_repository.find_commit(oid)
+    }
+
+    pub fn checkout_commit(&self, commit_oid: git::Oid) {
+        let commit = self.local_repository.find_commit(commit_oid).unwrap();
+        let commit_tree = commit.tree().unwrap();
+
+        self.local_repository.set_head_detached(commit_oid).unwrap();
+        self.local_repository
+            .checkout_tree(&commit_tree)
+            .force()
+            .checkout()
+            .unwrap();
+    }
+
+    pub fn checkout(&self, branch: &git::LocalRefname) {
+        let branch: git::Refname = branch.into();
+        let tree = match self.local_repository.find_branch(&branch) {
+            Ok(branch) => branch.peel_to_tree(),
+            Err(git::Error::NotFound(_)) => {
+                let head_commit = self
+                    .local_repository
+                    .head()
+                    .unwrap()
+                    .peel_to_commit()
+                    .unwrap();
+                self.local_repository
+                    .reference(&branch, head_commit.id(), false, "new branch")
+                    .unwrap();
+                head_commit.tree()
+            }
+            Err(error) => Err(error),
+        }
+        .unwrap();
+        self.local_repository.set_head(&branch).unwrap();
+        self.local_repository
+            .checkout_tree(&tree)
+            .force()
+            .checkout()
+            .unwrap();
+    }
+
+    /// takes all changes in the working directory and commits them into local
+    pub fn commit_all(&self, message: &str) -> git::Oid {
+        let head = self.local_repository.head().unwrap();
+        let mut index = self.local_repository.index().expect("failed to get index");
+        index
+            .add_all(["."], git2::IndexAddOption::DEFAULT, None)
+            .expect("failed to add all");
+        index.write().expect("failed to write index");
+        let oid = index.write_tree().expect("failed to write tree");
+        let signature = git::Signature::now("test", "test@email.com").unwrap();
+        self.local_repository
+            .commit(
+                head.name().as_ref(),
+                &signature,
+                &signature,
+                message,
+                &self
+                    .local_repository
+                    .find_tree(oid)
+                    .expect("failed to find tree"),
+                &[&self
+                    .local_repository
+                    .find_commit(
+                        self.local_repository
+                            .refname_to_id("HEAD")
+                            .expect("failed to get head"),
+                    )
+                    .expect("failed to find commit")],
+            )
+            .expect("failed to commit")
+    }
+
+    pub fn references(&self) -> Vec<git::Reference> {
+        self.local_repository
+            .references()
+            .expect("failed to get references")
+            .collect::<Result<Vec<_>, _>>()
+            .expect("failed to read references")
+    }
+
+    pub fn add_submodule(&self, url: &git::Url, path: &path::Path) {
+        let mut submodule = self.local_repository.add_submodule(url, path).unwrap();
+        let repo = submodule.open().unwrap();
+
+        // checkout submodule's master head
+        repo.find_remote("origin")
+            .unwrap()
+            .fetch(&["+refs/heads/*:refs/heads/*"], None, None)
+            .unwrap();
+        let reference = repo.find_reference("refs/heads/master").unwrap();
+        let reference_head = repo.find_commit(reference.target().unwrap()).unwrap();
+        repo.checkout_tree(reference_head.tree().unwrap().as_object(), None)
+            .unwrap();
+
+        // be sure that `HEAD` points to the actual head - `git2` seems to initialize it
+        // with `init.defaultBranch`, causing failure otherwise.
+        repo.set_head("refs/heads/master").unwrap();
+        submodule.add_finalize().unwrap();
+    }
+}