diff --git a/deltachat-ffi/src/lib.rs b/deltachat-ffi/src/lib.rs
index e9d7e6162..072930b96 100644
--- a/deltachat-ffi/src/lib.rs
+++ b/deltachat-ffi/src/lib.rs
@@ -63,7 +63,7 @@ pub type dc_context_t = Context;
 
 #[no_mangle]
 pub unsafe extern "C" fn dc_context_new(
-    os_name: *const libc::c_char,
+    _os_name: *const libc::c_char,
     dbfile: *const libc::c_char,
     blobdir: *const libc::c_char,
 ) -> *mut dc_context_t {
@@ -74,21 +74,11 @@ pub unsafe extern "C" fn dc_context_new(
         return ptr::null_mut();
     }
 
-    let os_name = if os_name.is_null() {
-        String::from("DcFFI")
-    } else {
-        to_string_lossy(os_name)
-    };
-
     let ctx = if blobdir.is_null() || *blobdir == 0 {
         use rand::Rng;
         // generate random ID as this functionality is not yet available on the C-api.
         let id = rand::thread_rng().gen();
-        block_on(Context::new(
-            os_name,
-            as_path(dbfile).to_path_buf().into(),
-            id,
-        ))
+        block_on(Context::new(as_path(dbfile).to_path_buf().into(), id))
     } else {
         eprintln!("blobdir can not be defined explicitly anymore");
         return ptr::null_mut();
@@ -3839,7 +3829,7 @@ pub type dc_accounts_t = AccountsWrapper;
 
 #[no_mangle]
 pub unsafe extern "C" fn dc_accounts_new(
-    os_name: *const libc::c_char,
+    _os_name: *const libc::c_char,
     dbfile: *const libc::c_char,
 ) -> *mut dc_accounts_t {
     setup_panic!();
@@ -3849,13 +3839,7 @@ pub unsafe extern "C" fn dc_accounts_new(
         return ptr::null_mut();
     }
 
-    let os_name = if os_name.is_null() {
-        String::from("DcFFI")
-    } else {
-        to_string_lossy(os_name)
-    };
-
-    let accs = block_on(Accounts::new(os_name, as_path(dbfile).to_path_buf().into()));
+    let accs = block_on(Accounts::new(as_path(dbfile).to_path_buf().into()));
 
     match accs {
         Ok(accs) => Box::into_raw(Box::new(AccountsWrapper::new(accs))),
diff --git a/examples/repl/main.rs b/examples/repl/main.rs
index 21ac12d0d..22eac2438 100644
--- a/examples/repl/main.rs
+++ b/examples/repl/main.rs
@@ -297,7 +297,7 @@ async fn start(args: Vec<String>) -> Result<(), Error> {
         println!("Error: Bad arguments, expected [db-name].");
         bail!("No db-name specified");
     }
-    let context = Context::new("CLI".into(), Path::new(&args[1]).to_path_buf(), 0).await?;
+    let context = Context::new(Path::new(&args[1]).to_path_buf(), 0).await?;
 
     let events = context.get_event_emitter();
     async_std::task::spawn(async move {
diff --git a/examples/simple.rs b/examples/simple.rs
index 2aa0ca960..fc875832c 100644
--- a/examples/simple.rs
+++ b/examples/simple.rs
@@ -36,7 +36,7 @@ async fn main() {
     let dir = tempdir().unwrap();
     let dbfile = dir.path().join("db.sqlite");
     log::info!("creating database {:?}", dbfile);
-    let ctx = Context::new("FakeOs".into(), dbfile.into(), 0)
+    let ctx = Context::new(dbfile.into(), 0)
         .await
         .expect("Failed to create context");
     let info = ctx.get_info().await;
diff --git a/src/accounts.rs b/src/accounts.rs
index 4885c0cab..7cc4d3e48 100644
--- a/src/accounts.rs
+++ b/src/accounts.rs
@@ -29,21 +29,21 @@ pub struct Accounts {
 
 impl Accounts {
     /// Loads or creates an accounts folder at the given `dir`.
-    pub async fn new(os_name: String, dir: PathBuf) -> Result<Self> {
+    pub async fn new(dir: PathBuf) -> Result<Self> {
         if !dir.exists().await {
-            Accounts::create(os_name, &dir).await?;
+            Accounts::create(&dir).await?;
         }
 
         Accounts::open(dir).await
     }
 
     /// Creates a new default structure.
-    pub async fn create(os_name: String, dir: &PathBuf) -> Result<()> {
+    pub async fn create(dir: &PathBuf) -> Result<()> {
         fs::create_dir_all(dir)
             .await
             .context("failed to create folder")?;
 
-        Config::new(os_name.clone(), dir).await?;
+        Config::new(dir).await?;
 
         Ok(())
     }
@@ -106,10 +106,9 @@ impl Accounts {
 
     /// Add a new account.
     pub async fn add_account(&mut self) -> Result<u32> {
-        let os_name = self.config.os_name().await;
         let account_config = self.config.new_account(&self.dir).await?;
 
-        let ctx = Context::new(os_name, account_config.dbfile().into(), account_config.id).await?;
+        let ctx = Context::new(account_config.dbfile().into(), account_config.id).await?;
         self.emitter.add_account(&ctx).await?;
         self.accounts.insert(account_config.id, ctx);
 
@@ -183,13 +182,7 @@ impl Accounts {
 
         match res {
             Ok(_) => {
-                let ctx = Context::with_blobdir(
-                    self.config.os_name().await,
-                    new_dbfile,
-                    new_blobdir,
-                    account_config.id,
-                )
-                .await?;
+                let ctx = Context::with_blobdir(new_dbfile, new_blobdir, account_config.id).await?;
                 self.emitter.add_account(&ctx).await?;
                 self.accounts.insert(account_config.id, ctx);
                 Ok(account_config.id)
@@ -349,7 +342,6 @@ pub struct Config {
 /// This is serialized into TOML.
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
 struct InnerConfig {
-    pub os_name: String,
     /// The currently selected account.
     pub selected_account: u32,
     pub next_id: u32,
@@ -357,9 +349,8 @@ struct InnerConfig {
 }
 
 impl Config {
-    pub async fn new(os_name: String, dir: &PathBuf) -> Result<Self> {
+    pub async fn new(dir: &PathBuf) -> Result<Self> {
         let inner = InnerConfig {
-            os_name,
             accounts: Vec::new(),
             selected_account: 0,
             next_id: 1,
@@ -374,10 +365,6 @@ impl Config {
         Ok(cfg)
     }
 
-    pub async fn os_name(&self) -> String {
-        self.inner.os_name.clone()
-    }
-
     /// Sync the inmemory representation to disk.
     async fn sync(&self) -> Result<()> {
         fs::write(&self.file, toml::to_string_pretty(&self.inner)?)
@@ -396,12 +383,7 @@ impl Config {
     pub async fn load_accounts(&self) -> Result<BTreeMap<u32, Context>> {
         let mut accounts = BTreeMap::new();
         for account_config in &self.inner.accounts {
-            let ctx = Context::new(
-                self.inner.os_name.clone(),
-                account_config.dbfile().into(),
-                account_config.id,
-            )
-            .await?;
+            let ctx = Context::new(account_config.dbfile().into(), account_config.id).await?;
             accounts.insert(account_config.id, ctx);
         }
 
@@ -498,7 +480,7 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let p: PathBuf = dir.path().join("accounts1").into();
 
-        let mut accounts1 = Accounts::new("my_os".into(), p.clone()).await.unwrap();
+        let mut accounts1 = Accounts::new(p.clone()).await.unwrap();
         accounts1.add_account().await.unwrap();
 
         let accounts2 = Accounts::open(p).await.unwrap();
@@ -516,7 +498,7 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let p: PathBuf = dir.path().join("accounts").into();
 
-        let mut accounts = Accounts::new("my_os".into(), p.clone()).await.unwrap();
+        let mut accounts = Accounts::new(p.clone()).await.unwrap();
         assert_eq!(accounts.accounts.len(), 0);
         assert_eq!(accounts.config.get_selected_account().await, 0);
 
@@ -543,7 +525,7 @@ mod tests {
         let dir = tempfile::tempdir()?;
         let p: PathBuf = dir.path().join("accounts").into();
 
-        let mut accounts = Accounts::new("my_os".into(), p.clone()).await?;
+        let mut accounts = Accounts::new(p.clone()).await?;
         assert!(accounts.get_selected_account().await.is_none());
         assert_eq!(accounts.config.get_selected_account().await, 0);
 
@@ -564,14 +546,12 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let p: PathBuf = dir.path().join("accounts").into();
 
-        let mut accounts = Accounts::new("my_os".into(), p.clone()).await.unwrap();
+        let mut accounts = Accounts::new(p.clone()).await.unwrap();
         assert_eq!(accounts.accounts.len(), 0);
         assert_eq!(accounts.config.get_selected_account().await, 0);
 
         let extern_dbfile: PathBuf = dir.path().join("other").into();
-        let ctx = Context::new("my_os".into(), extern_dbfile.clone(), 0)
-            .await
-            .unwrap();
+        let ctx = Context::new(extern_dbfile.clone(), 0).await.unwrap();
         ctx.set_config(crate::config::Config::Addr, Some("me@mail.com"))
             .await
             .unwrap();
@@ -601,7 +581,7 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let p: PathBuf = dir.path().join("accounts").into();
 
-        let mut accounts = Accounts::new("my_os".into(), p.clone()).await.unwrap();
+        let mut accounts = Accounts::new(p.clone()).await.unwrap();
 
         for expected_id in 1..10 {
             let id = accounts.add_account().await.unwrap();
@@ -621,7 +601,7 @@ mod tests {
         let dummy_accounts = 10;
 
         let (id0, id1, id2) = {
-            let mut accounts = Accounts::new("my_os".into(), p.clone()).await?;
+            let mut accounts = Accounts::new(p.clone()).await?;
             accounts.add_account().await?;
             let ids = accounts.get_all().await;
             assert_eq!(ids.len(), 1);
@@ -656,7 +636,7 @@ mod tests {
         assert!(id2 > id1 + dummy_accounts);
 
         let (id0_reopened, id1_reopened, id2_reopened) = {
-            let accounts = Accounts::new("my_os".into(), p.clone()).await?;
+            let accounts = Accounts::new(p.clone()).await?;
             let ctx = accounts.get_selected_account().await.unwrap();
             assert_eq!(
                 ctx.get_config(crate::config::Config::Addr).await?,
@@ -701,7 +681,7 @@ mod tests {
         let dir = tempfile::tempdir().unwrap();
         let p: PathBuf = dir.path().join("accounts").into();
 
-        let accounts = Accounts::new("my_os".into(), p.clone()).await?;
+        let accounts = Accounts::new(p.clone()).await?;
 
         // Make sure there are no accounts.
         assert_eq!(accounts.accounts.len(), 0);
diff --git a/src/context.rs b/src/context.rs
index ce3ddec38..c119035c1 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -47,7 +47,6 @@ pub struct InnerContext {
     /// Blob directory path
     pub(crate) blobdir: PathBuf,
     pub(crate) sql: Sql,
-    pub(crate) os_name: Option<String>,
     pub(crate) bob: Bob,
     pub(crate) last_smeared_timestamp: RwLock<i64>,
     pub(crate) running_state: RwLock<RunningState>,
@@ -108,7 +107,7 @@ pub fn get_info() -> BTreeMap<&'static str, String> {
 
 impl Context {
     /// Creates new context.
-    pub async fn new(os_name: String, dbfile: PathBuf, id: u32) -> Result<Context> {
+    pub async fn new(dbfile: PathBuf, id: u32) -> Result<Context> {
         // pretty_env_logger::try_init_timed().ok();
 
         let mut blob_fname = OsString::new();
@@ -118,11 +117,10 @@ impl Context {
         if !blobdir.exists().await {
             async_std::fs::create_dir_all(&blobdir).await?;
         }
-        Context::with_blobdir(os_name, dbfile, blobdir, id).await
+        Context::with_blobdir(dbfile, blobdir, id).await
     }
 
     pub(crate) async fn with_blobdir(
-        os_name: String,
         dbfile: PathBuf,
         blobdir: PathBuf,
         id: u32,
@@ -137,7 +135,6 @@ impl Context {
             id,
             blobdir,
             dbfile,
-            os_name: Some(os_name),
             running_state: RwLock::new(Default::default()),
             sql: Sql::new(),
             bob: Default::default(),
@@ -653,7 +650,7 @@ mod tests {
         let tmp = tempfile::tempdir().unwrap();
         let dbfile = tmp.path().join("db.sqlite");
         std::fs::write(&dbfile, b"123").unwrap();
-        let res = Context::new("FakeOs".into(), dbfile.into(), 1).await;
+        let res = Context::new(dbfile.into(), 1).await;
         assert!(res.is_err());
     }
 
@@ -804,9 +801,7 @@ mod tests {
     async fn test_blobdir_exists() {
         let tmp = tempfile::tempdir().unwrap();
         let dbfile = tmp.path().join("db.sqlite");
-        Context::new("FakeOS".into(), dbfile.into(), 1)
-            .await
-            .unwrap();
+        Context::new(dbfile.into(), 1).await.unwrap();
         let blobdir = tmp.path().join("db.sqlite-blobs");
         assert!(blobdir.is_dir());
     }
@@ -817,7 +812,7 @@ mod tests {
         let dbfile = tmp.path().join("db.sqlite");
         let blobdir = tmp.path().join("db.sqlite-blobs");
         std::fs::write(&blobdir, b"123").unwrap();
-        let res = Context::new("FakeOS".into(), dbfile.into(), 1).await;
+        let res = Context::new(dbfile.into(), 1).await;
         assert!(res.is_err());
     }
 
@@ -827,9 +822,7 @@ mod tests {
         let subdir = tmp.path().join("subdir");
         let dbfile = subdir.join("db.sqlite");
         let dbfile2 = dbfile.clone();
-        Context::new("FakeOS".into(), dbfile.into(), 1)
-            .await
-            .unwrap();
+        Context::new(dbfile.into(), 1).await.unwrap();
         assert!(subdir.is_dir());
         assert!(dbfile2.is_file());
     }
@@ -839,7 +832,7 @@ mod tests {
         let tmp = tempfile::tempdir().unwrap();
         let dbfile = tmp.path().join("db.sqlite");
         let blobdir = PathBuf::new();
-        let res = Context::with_blobdir("FakeOS".into(), dbfile.into(), blobdir, 1).await;
+        let res = Context::with_blobdir(dbfile.into(), blobdir, 1).await;
         assert!(res.is_err());
     }
 
@@ -848,7 +841,7 @@ mod tests {
         let tmp = tempfile::tempdir().unwrap();
         let dbfile = tmp.path().join("db.sqlite");
         let blobdir = tmp.path().join("blobs");
-        let res = Context::with_blobdir("FakeOS".into(), dbfile.into(), blobdir.into(), 1).await;
+        let res = Context::with_blobdir(dbfile.into(), blobdir.into(), 1).await;
         assert!(res.is_err());
     }
 
diff --git a/src/lib.rs b/src/lib.rs
index 5a4102f0c..45f4a14ea 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -12,7 +12,8 @@
 #![allow(
     clippy::match_bool,
     clippy::eval_order_dependence,
-    clippy::bool_assert_comparison
+    clippy::bool_assert_comparison,
+    clippy::manual_split_once
 )]
 
 #[macro_use]
diff --git a/src/oauth2.rs b/src/oauth2.rs
index f919a3faf..94060764e 100644
--- a/src/oauth2.rs
+++ b/src/oauth2.rs
@@ -41,6 +41,7 @@ struct Oauth2 {
 
 /// OAuth 2 Access Token Response
 #[derive(Debug, Deserialize)]
+#[allow(dead_code)]
 struct Response {
     // Should always be there according to: <https://www.oauth.com/oauth2-servers/access-tokens/access-token-response/>
     // but previous code handled its abscense.
diff --git a/src/pgp.rs b/src/pgp.rs
index 5068ff7d6..820dff34a 100644
--- a/src/pgp.rs
+++ b/src/pgp.rs
@@ -248,7 +248,7 @@ pub async fn pk_encrypt(
         let pkeys: Vec<SignedPublicKeyOrSubkey> = public_keys_for_encryption
             .keys()
             .iter()
-            .filter_map(|key| select_pk_for_encryption(key))
+            .filter_map(select_pk_for_encryption)
             .collect();
         let pkeys_refs: Vec<&SignedPublicKeyOrSubkey> = pkeys.iter().collect();
 
diff --git a/src/test_utils.rs b/src/test_utils.rs
index 525e42587..ab0d494f0 100644
--- a/src/test_utils.rs
+++ b/src/test_utils.rs
@@ -99,7 +99,7 @@ impl TestContext {
             let mut context_names = CONTEXT_NAMES.write().unwrap();
             context_names.insert(id, name);
         }
-        let ctx = Context::new("FakeOS".into(), dbfile.into(), id)
+        let ctx = Context::new(dbfile.into(), id)
             .await
             .expect("failed to create context");