diff --git a/.appveyor.yml b/.appveyor.yml
index 7031e615ef..f4fb0bad9e 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -16,7 +16,7 @@ environment:
   RUST_DIR: $(USERPROFILE)\rust
   CARGO_HOME: $(RUST_DIR)\cargo
   RUSTUP_HOME: $(RUST_DIR)\rustup
-  RUST_BACKTRACE: 1
+  RUST_BACKTRACE: full
   RUSTC_WRAPPER: sccache
   SCCACHE_BUCKET: deno-sccache
   AWS_ACCESS_KEY_ID: AKIAIVRN52PLDBP55LBQ
diff --git a/.travis.yml b/.travis.yml
index f975a5a91f..c1bdb22673 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ env:
   global:
   - CARGO_HOME=$TRAVIS_BUILD_DIR/third_party/rust_crates/
   - RUSTUP_HOME=$HOME/.rustup/
-  - RUST_BACKTRACE=1
+  - RUST_BACKTRACE=full
   - CARGO_TARGET_DIR=$HOME/target
   - PATH=$TRAVIS_BUILD_DIR/third_party/llvm-build/Release+Asserts/bin:$CARGO_HOME/bin:$PATH
   - RUSTC_WRAPPER=sccache