diff --git a/.circleci/config.yml b/.circleci/config.yml
index 0aacf1e57..20fe3538a 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -15,7 +15,7 @@ restore-workspace: &restore-workspace
 restore-cache: &restore-cache
   restore_cache:
     keys:
-      - cargo-v2-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
+      - cargo-v3-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
       - repo-source-{{ .Branch }}-{{ .Revision }}
 
 commands:
@@ -44,7 +44,7 @@ jobs:
           command: cargo generate-lockfile
       - restore_cache:
           keys:
-            - cargo-v2-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
+            - cargo-v3-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
       - run: rustup install $(cat rust-toolchain)
       - run: rustup default $(cat rust-toolchain)
       - run: rustup component add --toolchain $(cat rust-toolchain) rustfmt
@@ -60,7 +60,7 @@ jobs:
           paths:
             - crate
       - save_cache:
-          key: cargo-v2-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
+          key: cargo-v3-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
           paths:
             - "~/.cargo"
             - "~/.rustup"
@@ -121,7 +121,7 @@ jobs:
     steps:
       - checkout
       - run: bash ci_scripts/run-doxygen.sh
-      - run: mkdir -p workspace/c-docs 
+      - run: mkdir -p workspace/c-docs
       - run: cp -av deltachat-ffi/{html,xml} workspace/c-docs/
       - persist_to_workspace:
           root: workspace
@@ -189,7 +189,7 @@ workflows:
       - upload_docs_wheels:
           requires:
             - build_test_docs_wheel
-            - build_doxygen 
+            - build_doxygen
       - rustfmt:
           requires:
             - cargo_fetch
diff --git a/Cargo.lock b/Cargo.lock
index ddf51d236..e7c56c356 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -690,7 +690,7 @@ dependencies = [
  "serde_json 1.0.41 (registry+https://github.com/rust-lang/crates.io-index)",
  "sha2 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "smallvec 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "stop-token 0.1.2 (git+https://github.com/async-rs/stop-token)",
+ "stop-token 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "strum 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "strum_macros 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempfile 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2557,15 +2557,6 @@ name = "static_assertions"
 version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "stop-token"
-version = "0.1.2"
-source = "git+https://github.com/async-rs/stop-token#d9cef9b080069c5d800bcd477de3fd74300c2863"
-dependencies = [
- "async-std 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "pin-project-lite 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "stop-token"
 version = "0.1.2"
@@ -3573,7 +3564,6 @@ dependencies = [
 "checksum spin 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 "checksum stable_deref_trait 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "dba1a27d3efae4351c8051072d619e3ade2820635c3958d826bfea39d59b54c8"
 "checksum static_assertions 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "7f3eb36b47e512f8f1c9e3d10c2c1965bc992bd9cdb024fa581e2194501c83d3"
-"checksum stop-token 0.1.2 (git+https://github.com/async-rs/stop-token)" = "<none>"
 "checksum stop-token 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "06855fb7c94d3be9b3a57c4d82dfc8a43bb658fbb3b1dda79de89e748d9eb9dd"
 "checksum stream-cipher 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "8131256a5896cabcf5eb04f4d6dacbe1aefda854b0d9896e09cb58829ec5638c"
 "checksum string 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d24114bfcceb867ca7f71a0d3fe45d45619ec47a6fbfa98cb14e14250bfa5d6d"
diff --git a/Cargo.toml b/Cargo.toml
index edb222007..65dc51d36 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -50,7 +50,7 @@ bitflags = "1.1.0"
 jetscii = "0.4.4"
 debug_stub_derive = "0.3.0"
 sanitize-filename = "0.2.1"
-stop-token = { git = "https://github.com/async-rs/stop-token" }
+stop-token = { version = "0.1.1", features = ["unstable"] }
 rustls = "0.16.0"
 webpki-roots = "0.18.0"
 
diff --git a/rust-toolchain b/rust-toolchain
index 202ebf953..22e904890 100644
--- a/rust-toolchain
+++ b/rust-toolchain
@@ -1 +1 @@
-nightly-2019-09-12
+nightly-2019-11-06
diff --git a/src/e2ee.rs b/src/e2ee.rs
index 805ad47be..7780d4dcd 100644
--- a/src/e2ee.rs
+++ b/src/e2ee.rs
@@ -498,7 +498,7 @@ fn decrypt_if_autocrypt_message(
     public_keyring_for_validate: &Keyring,
     ret_valid_signatures: &mut HashSet<String>,
     ret_gossip_headers: *mut *mut mailimf_fields,
-) -> Result<(bool)> {
+) -> Result<bool> {
     /* The returned bool is true if we detected an Autocrypt-encrypted
     message and successfully decrypted it. Decryption then modifies the
     passed in mime structure in place. The returned bool is false