diff --git a/.changelog/2726.trivial.md b/.changelog/2726.trivial.md
new file mode 100644
index 00000000000..13e2bdc0926
--- /dev/null
+++ b/.changelog/2726.trivial.md
@@ -0,0 +1,4 @@
+rust-toolchain: add rust-toolchain containing nightly-2020-02-16.
+The rust-toolchain file overrides rustup's default toolchain when invoking
+cargo, rustc, and friends. This is helpful when working on multiple projects
+that use different rust versions.
diff --git a/rust-toolchain b/rust-toolchain
new file mode 100644
index 00000000000..1c0dbb84427
--- /dev/null
+++ b/rust-toolchain
@@ -0,0 +1 @@
+nightly-2020-02-16