diff --git a/.travis.yml b/.travis.yml
index d56112a3..7175ae4a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -204,6 +204,9 @@ matrix:
       stage: tier2
     - env: TARGET=x86_64-unknown-linux-musl
       stage: tier2
+    - env: TARGET=wasm32-unknown-wasi
+      rust: nightly
+      stage: tier2
 
   allow_failures:
       # FIXME: android build bots time out irregularly
diff --git a/ci/docker/wasm32-unknown-wasi/Dockerfile b/ci/docker/wasm32-unknown-wasi/Dockerfile
index b09cacb6..6f464404 100644
--- a/ci/docker/wasm32-unknown-wasi/Dockerfile
+++ b/ci/docker/wasm32-unknown-wasi/Dockerfile
@@ -28,7 +28,7 @@ RUN mv /clang+llvm-8.0.0-x86_64-linux-gnu-ubuntu-18.04 /wasmcc
 # those breaking changes on `libc`'s own CI
 RUN git clone https://github.com/CraneStation/wasi-sysroot && \
   cd wasi-sysroot && \
-  git reset --hard 320054e84f8f2440def3b1c8700cedb8fd697bf8
+  git reset --hard e5f14be38362f1ab83302895a6e74b2ffd0e2302
 RUN make -C wasi-sysroot install -j $(nproc) WASM_CC=/wasmcc/bin/clang INSTALL_DIR=/wasi-sysroot
 
 # This is a small wrapper script which executes the actual clang binary in
@@ -58,9 +58,9 @@ RUN curl -sSf https://sh.rustup.rs |  sh -s -- -y
 ENV PATH=/root/.cargo/bin:$PATH
 
 RUN apt-get install -y --no-install-recommends python
-RUN git clone https://github.com/CraneStation/wasmtime-wasi wasmtime && \
+RUN git clone https://github.com/CraneStation/wasmtime wasmtime && \
   cd wasmtime && \
-  git reset --hard 4fe2d6084e5b5cc74e69a26860f12750df51d339
+  git reset --hard a1c123c3dd8f9766990efe0f1734a646f61ba8a0
 RUN cargo build --release --manifest-path wasmtime/Cargo.toml
 
 # And finally in the last image we're going to assemble everything together.
@@ -72,12 +72,13 @@ RUN apt-get update && \
     apt-get install -y --no-install-recommends \
     gcc \
     libc6-dev \
-    libxml2
+    libxml2 \
+    ca-certificates
 
 # Copy over clang we downloaded to link executables ...
-COPY --from=reference-sysroot /wasmcc /wasmcc/
+COPY --from=wasi-sysroot /wasmcc /wasmcc/
 # ... and the sysroot we built to link executables against ...
-COPY --from=reference-sysroot /wasi-sysroot/ /wasi-sysroot/
+COPY --from=wasi-sysroot /wasi-sysroot/ /wasi-sysroot/
 # ... and finally wasmtime to actually execute binaries
 COPY --from=wasmtime /wasmtime/target/release/wasmtime /usr/bin/
 
diff --git a/libc-test/build.rs b/libc-test/build.rs
index ed40ddc3..72ebbb3c 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -1890,6 +1890,7 @@ fn test_wasi(target: &str) {
         "unistd.h",
         "wasi/core.h",
         "wasi/libc.h",
+        "wasi/libc-find-relpath.h",
         "wchar.h",
     }
 
diff --git a/src/wasi.rs b/src/wasi.rs
index 13af0b53..77c48f50 100644
--- a/src/wasi.rs
+++ b/src/wasi.rs
@@ -388,11 +388,14 @@ pub const __WASI_WHENCE_CUR: u8 = 0;
 pub const __WASI_WHENCE_END: u8 = 1;
 pub const __WASI_WHENCE_SET: u8 = 2;
 
-#[cfg_attr(feature = "rustc-dep-of-std",
-           link(name = "c", kind = "static",
-                cfg(target_feature = "crt-static")))]
-#[cfg_attr(feature = "rustc-dep-of-std",
-           link(name = "c", cfg(not(target_feature = "crt-static"))))]
+#[cfg_attr(
+    feature = "rustc-dep-of-std",
+    link(name = "c", kind = "static", cfg(target_feature = "crt-static"))
+)]
+#[cfg_attr(
+    feature = "rustc-dep-of-std",
+    link(name = "c", cfg(not(target_feature = "crt-static")))
+)]
 extern {
     pub fn _Exit(code: c_int) -> !;
     pub fn _exit(code: c_int) -> !;
@@ -494,6 +497,12 @@ extern {
     pub fn __wasilibc_rmfileat(fd: c_int, path: *const c_char) -> c_int;
     pub fn __wasilibc_rmdirat(fd: c_int, path: *const c_char) -> c_int;
     pub fn __wasilibc_init_preopen();
+    pub fn __wasilibc_find_relpath(
+        path: *const c_char,
+        rights_base: __wasi_rights_t,
+        rights_inheriting: __wasi_rights_t,
+        relative_path: *mut *const c_char,
+    ) -> c_int;
 
     pub fn arc4random() -> u32;
     pub fn arc4random_buf(a: *mut c_void, b: size_t);