diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8c337f418..20c256654 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -24,7 +24,7 @@ jobs:
     name: Lint Rust
     runs-on: ubuntu-latest
     env:
-      RUSTUP_TOOLCHAIN: 1.74.1
+      RUSTUP_TOOLCHAIN: 1.75.0
     steps:
       - uses: actions/checkout@v3
       - name: Install rustfmt and clippy
@@ -76,11 +76,11 @@ jobs:
       matrix:
         include:
           - os: ubuntu-latest
-            rust: 1.74.1
+            rust: 1.75.0
           - os: windows-latest
-            rust: 1.74.1
+            rust: 1.75.0
           - os: macos-latest
-            rust: 1.74.1
+            rust: 1.75.0
 
           # Minimum Supported Rust Version = 1.70.0
           - os: ubuntu-latest
diff --git a/deltachat-jsonrpc/src/api/types/chat.rs b/deltachat-jsonrpc/src/api/types/chat.rs
index 8603c202e..233e29a87 100644
--- a/deltachat-jsonrpc/src/api/types/chat.rs
+++ b/deltachat-jsonrpc/src/api/types/chat.rs
@@ -85,7 +85,7 @@ impl FullChat {
         let can_send = chat.can_send(context).await?;
 
         let was_seen_recently = if chat.get_type() == Chattype::Single {
-            match contact_ids.get(0) {
+            match contact_ids.first() {
                 Some(contact) => Contact::get_by_id(context, *contact)
                     .await
                     .context("failed to load contact for was_seen_recently")?
diff --git a/deltachat-jsonrpc/src/api/types/chat_list.rs b/deltachat-jsonrpc/src/api/types/chat_list.rs
index b47f7a728..4b39a17be 100644
--- a/deltachat-jsonrpc/src/api/types/chat_list.rs
+++ b/deltachat-jsonrpc/src/api/types/chat_list.rs
@@ -102,7 +102,7 @@ pub(crate) async fn get_chat_list_item_by_id(
     let self_in_group = chat_contacts.contains(&ContactId::SELF);
 
     let (dm_chat_contact, was_seen_recently) = if chat.get_type() == Chattype::Single {
-        let contact = chat_contacts.get(0);
+        let contact = chat_contacts.first();
         let was_seen_recently = match contact {
             Some(contact) => Contact::get_by_id(ctx, *contact)
                 .await
diff --git a/src/accounts.rs b/src/accounts.rs
index 8e0dd0a2a..e0d39c952 100644
--- a/src/accounts.rs
+++ b/src/accounts.rs
@@ -546,8 +546,12 @@ impl Config {
             }
             if self.inner.selected_account == id {
                 // reset selected account
-                self.inner.selected_account =
-                    self.inner.accounts.get(0).map(|e| e.id).unwrap_or_default();
+                self.inner.selected_account = self
+                    .inner
+                    .accounts
+                    .first()
+                    .map(|e| e.id)
+                    .unwrap_or_default();
             }
         }
 
diff --git a/src/contact.rs b/src/contact.rs
index d390feca9..f4a2702e2 100644
--- a/src/contact.rs
+++ b/src/contact.rs
@@ -1885,12 +1885,12 @@ mod tests {
         // Search by name.
         let contacts = Contact::get_all(&context.ctx, 0, Some("bob")).await?;
         assert_eq!(contacts.len(), 1);
-        assert_eq!(contacts.get(0), Some(&id));
+        assert_eq!(contacts.first(), Some(&id));
 
         // Search by address.
         let contacts = Contact::get_all(&context.ctx, 0, Some("user")).await?;
         assert_eq!(contacts.len(), 1);
-        assert_eq!(contacts.get(0), Some(&id));
+        assert_eq!(contacts.first(), Some(&id));
 
         let contacts = Contact::get_all(&context.ctx, 0, Some("alice")).await?;
         assert_eq!(contacts.len(), 0);
@@ -1917,7 +1917,7 @@ mod tests {
         // Search by display name (same as manually set name).
         let contacts = Contact::get_all(&context.ctx, 0, Some("someone")).await?;
         assert_eq!(contacts.len(), 1);
-        assert_eq!(contacts.get(0), Some(&id));
+        assert_eq!(contacts.first(), Some(&id));
 
         Ok(())
     }
diff --git a/src/context.rs b/src/context.rs
index 57ecff7a3..ebadb60bf 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -1370,7 +1370,7 @@ mod tests {
         assert_eq!(res.len(), 2);
 
         // Message added later is returned first.
-        assert_eq!(res.get(0), Some(&msg2.id));
+        assert_eq!(res.first(), Some(&msg2.id));
         assert_eq!(res.get(1), Some(&msg1.id));
 
         // Global search with longer text does not find any message.
@@ -1587,7 +1587,7 @@ mod tests {
 
         let bob_next_msg_ids = bob.get_next_msgs().await?;
         assert_eq!(bob_next_msg_ids.len(), 1);
-        assert_eq!(bob_next_msg_ids.get(0), Some(&received_msg.id));
+        assert_eq!(bob_next_msg_ids.first(), Some(&received_msg.id));
 
         bob.set_config_u32(Config::LastMsgId, received_msg.id.to_u32())
             .await?;
@@ -1596,7 +1596,7 @@ mod tests {
         // Next messages include self-sent messages.
         let alice_next_msg_ids = alice.get_next_msgs().await?;
         assert_eq!(alice_next_msg_ids.len(), 1);
-        assert_eq!(alice_next_msg_ids.get(0), Some(&sent_msg.sender_msg_id));
+        assert_eq!(alice_next_msg_ids.first(), Some(&sent_msg.sender_msg_id));
 
         alice
             .set_config_u32(Config::LastMsgId, sent_msg.sender_msg_id.to_u32())
diff --git a/src/imex/transfer.rs b/src/imex/transfer.rs
index 545bd94bd..398fb1d9f 100644
--- a/src/imex/transfer.rs
+++ b/src/imex/transfer.rs
@@ -638,7 +638,7 @@ mod tests {
         let self_chat = ctx1.get_self_chat().await;
         let msgs = get_chat_msgs(&ctx1, self_chat.id).await.unwrap();
         assert_eq!(msgs.len(), 2);
-        let msgid = match msgs.get(0).unwrap() {
+        let msgid = match msgs.first().unwrap() {
             ChatItem::Message { msg_id } => msg_id,
             _ => panic!("wrong chat item"),
         };
diff --git a/src/location.rs b/src/location.rs
index 455997813..79c96958f 100644
--- a/src/location.rs
+++ b/src/location.rs
@@ -954,7 +954,7 @@ Content-Disposition: attachment; filename="location.kml"
         assert!(msg.chat_id == bob_chat_id);
         assert_eq!(msg.msg_ids.len(), 1);
 
-        let bob_msg = Message::load_from_db(&bob, *msg.msg_ids.get(0).unwrap()).await?;
+        let bob_msg = Message::load_from_db(&bob, *msg.msg_ids.first().unwrap()).await?;
         assert_eq!(bob_msg.chat_id, bob_chat_id);
         assert_eq!(bob_msg.viewtype, Viewtype::Image);
 
diff --git a/src/mimeparser.rs b/src/mimeparser.rs
index 0d1acef8f..90c2384c9 100644
--- a/src/mimeparser.rs
+++ b/src/mimeparser.rs
@@ -914,7 +914,7 @@ impl MimeMessage {
                 skip the rest.  (see
                 <https://k9mail.app/2016/11/24/OpenPGP-Considerations-Part-I.html>
                 for background information why we use encrypted+signed) */
-                if let Some(first) = mail.subparts.get(0) {
+                if let Some(first) = mail.subparts.first() {
                     any_part_added = self
                         .parse_mime_recursive(context, first, is_related)
                         .await?;
@@ -970,7 +970,7 @@ impl MimeMessage {
                             }
                         }
                         Some(_) => {
-                            if let Some(first) = mail.subparts.get(0) {
+                            if let Some(first) = mail.subparts.first() {
                                 any_part_added = self
                                     .parse_mime_recursive(context, first, is_related)
                                     .await?;
diff --git a/src/reaction.rs b/src/reaction.rs
index 2b8e22020..2fec8a0e8 100644
--- a/src/reaction.rs
+++ b/src/reaction.rs
@@ -425,7 +425,7 @@ Content-Disposition: reaction\n\
         let contacts = reactions.contacts();
         assert_eq!(contacts.len(), 1);
 
-        assert_eq!(contacts.get(0), Some(&bob_id));
+        assert_eq!(contacts.first(), Some(&bob_id));
         let bob_reaction = reactions.get(bob_id);
         assert_eq!(bob_reaction.is_empty(), false);
         assert_eq!(bob_reaction.emojis(), vec!["👍"]);
@@ -526,7 +526,7 @@ Here's my footer -- bob@example.net"
         assert_eq!(reactions.to_string(), "👍1");
         let contacts = reactions.contacts();
         assert_eq!(contacts.len(), 1);
-        let bob_id = contacts.get(0).unwrap();
+        let bob_id = contacts.first().unwrap();
         let bob_reaction = reactions.get(*bob_id);
         assert_eq!(bob_reaction.is_empty(), false);
         assert_eq!(bob_reaction.emojis(), vec!["👍"]);
@@ -578,13 +578,13 @@ Here's my footer -- bob@example.net"
         )
         .await?
         .unwrap();
-        let alice_msg_id = *alice_received_message.msg_ids.get(0).unwrap();
+        let alice_msg_id = *alice_received_message.msg_ids.first().unwrap();
 
         // Bob downloads own message on the other device.
         let bob_received_message = receive_imf(&bob, msg_full.as_bytes(), false)
             .await?
             .unwrap();
-        let bob_msg_id = *bob_received_message.msg_ids.get(0).unwrap();
+        let bob_msg_id = *bob_received_message.msg_ids.first().unwrap();
 
         // Bob reacts to own message.
         send_reaction(&bob, bob_msg_id, "👍").await.unwrap();
diff --git a/src/receive_imf.rs b/src/receive_imf.rs
index bd72ff61e..30e0ba5dd 100644
--- a/src/receive_imf.rs
+++ b/src/receive_imf.rs
@@ -315,7 +315,7 @@ pub(crate) async fn receive_imf_inner(
             mime_parser.decryption_info.peerstate =
                 Peerstate::from_addr(context, contact.get_addr()).await?;
         } else {
-            let to_id = to_ids.get(0).copied().unwrap_or_default();
+            let to_id = to_ids.first().copied().unwrap_or_default();
             // handshake may mark contacts as verified and must be processed before chats are created
             res = observe_securejoin_on_other_device(context, &mime_parser, to_id)
                 .await
@@ -919,7 +919,7 @@ async fn add_parts(
         // the mail is on the IMAP server, probably it is also delivered.
         // We cannot recreate other states (read, error).
         state = MessageState::OutDelivered;
-        to_id = to_ids.get(0).copied().unwrap_or_default();
+        to_id = to_ids.first().copied().unwrap_or_default();
 
         let self_sent =
             from_id == ContactId::SELF && to_ids.len() == 1 && to_ids.contains(&ContactId::SELF);
diff --git a/src/sync.rs b/src/sync.rs
index 4162f57e5..64873298b 100644
--- a/src/sync.rs
+++ b/src/sync.rs
@@ -447,7 +447,7 @@ mod tests {
         )?;
         assert_eq!(sync_items.items.len(), 1);
         let SyncDataOrUnknown::SyncData(AlterChat { id, action }) =
-            &sync_items.items.get(0).unwrap().data
+            &sync_items.items.first().unwrap().data
         else {
             bail!("bad item");
         };
@@ -491,7 +491,7 @@ mod tests {
 
         assert_eq!(sync_items.items.len(), 1);
         if let SyncDataOrUnknown::SyncData(AddQrToken(token)) =
-            &sync_items.items.get(0).unwrap().data
+            &sync_items.items.first().unwrap().data
         {
             assert_eq!(token.invitenumber, "in");
             assert_eq!(token.auth, "yip");
diff --git a/src/webxdc.rs b/src/webxdc.rs
index e107c8782..12a51ed53 100644
--- a/src/webxdc.rs
+++ b/src/webxdc.rs
@@ -1241,7 +1241,7 @@ mod tests {
         )
         .await?
         .unwrap();
-        assert_eq!(*received_msg.msg_ids.get(0).unwrap(), bob_instance.id);
+        assert_eq!(*received_msg.msg_ids.first().unwrap(), bob_instance.id);
         let bob_instance = bob.get_last_msg().await;
         assert_eq!(bob_instance.viewtype, Viewtype::Webxdc);
         assert_eq!(bob_instance.download_state, DownloadState::Done);