diff --git a/extra/rust/build b/extra/rust/build
index 5e69e3da..96a5d696 100755
--- a/extra/rust/build
+++ b/extra/rust/build
@@ -1,6 +1,5 @@
 #!/bin/sh -e
 
-rm -f vendor/curl-sys/.cargo-checksum.json
 patch -p1 < fix-curl.patch
 
 # Instruct the compiler to trim absolute paths in resulting binaries and instead
@@ -11,7 +10,7 @@ export RUSTFLAGS="$RUSTFLAGS --remap-path-prefix=$PWD=."
 # bootstrap library to allow for the removal of the internet
 # connection requirement per build.
 {
-    mkdir -p "${cache_dir:=build/cache/2021-07-29}"
+    mkdir -p "${cache_dir:=build/cache/2021-09-09}"
 
     for tarball in *.tar.xz\?no-extract; do
         mv -f "$tarball" "$cache_dir/${tarball%%\?no-extract}"
@@ -31,6 +30,9 @@ done
 sed 's/\("files":{\)[^}]*/\1/' \
     vendor/rustc-ap-rustc_target/.cargo-checksum.json > _
 mv -f _ vendor/rustc-ap-rustc_target/.cargo-checksum.json
+sed 's/\("files":{\)[^}]*/\1/' \
+    vendor/curl-sys/.cargo-checksum.json > _
+mv -f _ vendor/curl-sys/.cargo-checksum.json
 
 cat > config.toml <<EOF
 [llvm]
diff --git a/extra/rust/checksums b/extra/rust/checksums
index a6af0fa8..0bac09b0 100644
--- a/extra/rust/checksums
+++ b/extra/rust/checksums
@@ -1,5 +1,5 @@
-aec85a7c1f40b7a40818a58ae13632f8a12cfaa4d3e2a10957d0e9d16dfdd556
-c2de24eb3e524c0fdd1e8116f578c103035da1ece1e4c06efab67999180eefe8
-5cffd160f5daac521652ee67c62947c0d66bdc8e5ebf7dc93114cdff9a934b0b
-9a26b73e578227d111b221932d7cbeaf4b41f27a0f7597a49efb81e2bd0791f9
-f68fbed74118bff6df74dbdd1507e646e6627c95444fde90a6bb66b51b677cff
+f13468889833c88e744ad579c5d8fbb7ecb53216159b54481a90e5dcdaa9e320
+a7f02bd5b4fd2b1f55edaddfa869d2ce210ce4951cb752ce7b380129bc2d1882
+0ddf6eccc6d005d39aaad3246ff157811a5a81c801f6e935c671299d24036c50
+9faa4514576c4beafcc7b640a17b57e8103f2f9c88f646c216ccce90b1a0cdf2
+2be91d7548e55476a4e62aca25dae606a06a36ef30b51af4da5bec4da400c3b0
diff --git a/extra/rust/patches/fix-curl.patch b/extra/rust/patches/fix-curl.patch
index df30f42b..3e9e182f 100644
--- a/extra/rust/patches/fix-curl.patch
+++ b/extra/rust/patches/fix-curl.patch
@@ -1,33 +1,13 @@
-diff --git a/Cargo.lock b/Cargo.lock
-index 085aae3..ccedf97 100644
---- a/Cargo.lock
-+++ b/Cargo.lock
-@@ -873,7 +873,7 @@ dependencies = [
- name = "curl-sys"
- version = "0.4.45+curl-7.78.0"
- source = "registry+https://github.com/rust-lang/crates.io-index"
--checksum = "de9e5a72b1c744eb5dd20b2be4d7eb84625070bb5c4ab9b347b70464ab1e62eb"
-+checksum = "d8f1e2562c5784ad3348906a9c7e2e435c8bc5c8796a4398d322456d9a2710c1"
- dependencies = [
-  "cc",
-  "libc",
-diff --git a/vendor/curl-sys/.cargo-checksum.json b/vendor/curl-sys/.cargo-checksum.json
-new file mode 100644
-index 0000000..b3a3efe
---- /dev/null
-+++ b/vendor/curl-sys/.cargo-checksum.json
-@@ -0,0 +1 @@
-+{"files":{},"package":"d8f1e2562c5784ad3348906a9c7e2e435c8bc5c8796a4398d322456d9a2710c1"}
 diff --git a/vendor/curl-sys/build.rs b/vendor/curl-sys/build.rs
-index 7b66756..a7c7122 100644
+index 24475cc..3249440 100644
 --- a/vendor/curl-sys/build.rs
 +++ b/vendor/curl-sys/build.rs
-@@ -109,6 +109,8 @@ fn main() {
+@@ -111,6 +111,8 @@ fn main() {
          .include("curl/lib")
          .include("curl/include")
          .define("BUILDING_LIBCURL", None)
 +        .define("CURL_CA_BUNDLE", "\"/etc/ssl/cert.pem\"")
 +        .define("CURL_CA_PATH", "\"/etc/ssl/certs\"")
-         .define("CURL_DISABLE_CRYPTO_AUTH", None)
          .define("CURL_DISABLE_DICT", None)
          .define("CURL_DISABLE_GOPHER", None)
+         .define("CURL_DISABLE_IMAP", None)
diff --git a/extra/rust/sources b/extra/rust/sources
index e6e616e7..4aaf4f86 100644
--- a/extra/rust/sources
+++ b/extra/rust/sources
@@ -1,5 +1,5 @@
 https://static.rust-lang.org/dist/rustc-VERSION-src.tar.xz
-https://static.rust-lang.org/dist/2021-07-29/rust-std-1.54.0-x86_64-unknown-linux-musl.tar.xz?no-extract
-https://static.rust-lang.org/dist/2021-07-29/rustc-1.54.0-x86_64-unknown-linux-musl.tar.xz?no-extract
-https://static.rust-lang.org/dist/2021-07-29/cargo-1.54.0-x86_64-unknown-linux-musl.tar.xz?no-extract
+https://static.rust-lang.org/dist/2021-09-09/rust-std-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
+https://static.rust-lang.org/dist/2021-09-09/rustc-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
+https://static.rust-lang.org/dist/2021-09-09/cargo-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
 patches/fix-curl.patch
diff --git a/extra/rust/version b/extra/rust/version
index 3578e79c..ad91362f 100644
--- a/extra/rust/version
+++ b/extra/rust/version
@@ -1 +1 @@
-1.55.0 3
+1.56.0 2
diff --git a/testing/rust/README b/testing/rust/README
deleted file mode 100644
index 4c3d616f..00000000
--- a/testing/rust/README
+++ /dev/null
@@ -1,46 +0,0 @@
-rust
-________________________________________________________________________________
-
-Rust is a multi-paradigm, high-level, general-purpose programming language
-designed for performance and safety, especially safe concurrency. Rust is
-syntactically similar to C++, but can guarantee memory safety by using a borrow
-checker to validate references. Rust achieves memory safety without garbage
-collection, and reference counting is optional.
-
-Rust was originally designed by Graydon Hoare at Mozilla Research, with
-contributions from Dave Herman, Brendan Eich, and others. The designers refined
-the language while writing the Servo experimental browser engine, and the Rust
-compiler. [0]
-
-Upstream: https://www.rust-lang.org/
-
-
-[000] Index
-________________________________________________________________________________
-
-* Installation ........................................................... [001]
-* Usage .................................................................. [002]
-* References ............................................................. [003]
-
-
-[001] Installation
-________________________________________________________________________________
-
-+------------------------------------------------------------------------------+
-|                                                                              |
-|  $ kiss b rust                                                               |
-|                                                                              |
-+------------------------------------------------------------------------------+
-
-
-[002] Usage
-________________________________________________________________________________
-
-Refer to the manual pages and command help output.
-
-
-[003] References
-________________________________________________________________________________
-
-[0] https://en.wikipedia.org/wiki/Rust_(programming_language)
-
diff --git a/testing/rust/build b/testing/rust/build
deleted file mode 100755
index c6f8c737..00000000
--- a/testing/rust/build
+++ /dev/null
@@ -1,107 +0,0 @@
-#!/bin/sh -e
-
-# Instruct the compiler to trim absolute paths in resulting binaries and instead
-# change them to relative paths ($PWD/... ./...).
-export RUSTFLAGS="$RUSTFLAGS --remap-path-prefix=$PWD=."
-
-# This package mimics the download process of rust's 'x.py'
-# bootstrap library to allow for the removal of the internet
-# connection requirement per build.
-{
-    mkdir -p "${cache_dir:=build/cache/2021-09-09}"
-
-    for tarball in *.tar.xz\?no-extract; do
-        mv -f "$tarball" "$cache_dir/${tarball%%\?no-extract}"
-    done
-}
-
-# Set shared linking as the default.
-for f in \
-    compiler/rustc_target/src/spec/linux_musl_base.rs \
-    vendor/rustc-ap-rustc_target/src/spec/linux_musl_base.rs
-do
-    sed 's/\(crt_static_default = \)true/\1false/' "$f" > _
-    mv -f _ "$f"
-done
-
-# Ignore checksums of files modified above.
-sed 's/\("files":{\)[^}]*/\1/' \
-    vendor/rustc-ap-rustc_target/.cargo-checksum.json > _
-mv -f _ vendor/rustc-ap-rustc_target/.cargo-checksum.json
-
-cat > config.toml <<EOF
-[llvm]
-link-shared = true
-skip-rebuild = true
-
-[build]
-build     = "x86_64-unknown-linux-musl"
-host      = [ "x86_64-unknown-linux-musl" ]
-target    = [ "x86_64-unknown-linux-musl" ]
-
-docs           = false
-compiler-docs  = false
-extended       = true
-submodules     = false
-python         = "python3"
-locked-deps    = true
-vendor         = true
-tools          = [ "cargo", "rustfmt" ]
-sanitizers     = false
-profiler       = false
-full-bootstrap = false
-
-[install]
-prefix = "/usr"
-
-[target.x86_64-unknown-linux-musl]
-llvm-config = "/usr/bin/llvm-config"
-crt-static  = false
-sanitizers  = false
-
-[dist]
-src-tarball = false
-
-[rust]
-backtrace         = false
-channel           = "stable"
-codegen-tests     = false
-codegen-units-std = 1
-codegen-units     = 0
-debug             = false
-debug-assertions  = false
-debuginfo-level   = 0
-incremental       = false
-jemalloc          = false
-rpath             = false
-dist-src          = false
-EOF
-
-# Workaround to get Rust to build in llvm-only environments.
-# libgcc_s.so is needed for Rust's bootstrap binaries, on llvm-only systems
-# this library does not exist. This hack creates it as alias to libunwind.
-case $("$CC" -print-file-name=libunwind.so) in */*)
-    printf 'llvm-libunwind = "system"\n' >> config.toml
-
-    mkdir -p libgcc
-
-    printf 'INPUT(-lunwind)\n' > \
-        libgcc/libgcc_s.so
-
-    ln -sf "$KISS_ROOT/usr/lib/libunwind.so.1" \
-        libgcc/libgcc_s.so.1
-
-    export \
-        LD_LIBRARY_PATH="$PWD/libgcc:$LD_LIBRARY_PATH" \
-        LIBRARY_PATH="$PWD/libgcc:$LIBRARY_PATH"
-esac
-
-./x.py build -j "$(grep -scF 'core id' /proc/cpuinfo)"
-./x.py install
-
-rm -rf \
-    "$1/usr/lib/rustlib/src/" \
-    "$1/usr/share/doc" \
-    "$1/usr/share/zsh" \
-    "$1/usr/lib/rustlib/uninstall.sh"
-
diff --git a/testing/rust/checksums b/testing/rust/checksums
deleted file mode 100644
index 8f698d07..00000000
--- a/testing/rust/checksums
+++ /dev/null
@@ -1,5 +0,0 @@
-f13468889833c88e744ad579c5d8fbb7ecb53216159b54481a90e5dcdaa9e320
-a7f02bd5b4fd2b1f55edaddfa869d2ce210ce4951cb752ce7b380129bc2d1882
-0ddf6eccc6d005d39aaad3246ff157811a5a81c801f6e935c671299d24036c50
-9faa4514576c4beafcc7b640a17b57e8103f2f9c88f646c216ccce90b1a0cdf2
-f68fbed74118bff6df74dbdd1507e646e6627c95444fde90a6bb66b51b677cff
diff --git a/testing/rust/depends b/testing/rust/depends
deleted file mode 100644
index f70e18ce..00000000
--- a/testing/rust/depends
+++ /dev/null
@@ -1,8 +0,0 @@
-cmake   make
-curl    make
-llvm
-openssl
-pkgconf make
-python  make
-xz
-zlib
diff --git a/testing/rust/sources b/testing/rust/sources
deleted file mode 100644
index a1b23850..00000000
--- a/testing/rust/sources
+++ /dev/null
@@ -1,4 +0,0 @@
-https://static.rust-lang.org/dist/rustc-VERSION-src.tar.xz
-https://static.rust-lang.org/dist/2021-09-09/rust-std-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
-https://static.rust-lang.org/dist/2021-09-09/rustc-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
-https://static.rust-lang.org/dist/2021-09-09/cargo-1.55.0-x86_64-unknown-linux-musl.tar.xz?no-extract
diff --git a/testing/rust/version b/testing/rust/version
deleted file mode 100644
index 89bac5a7..00000000
--- a/testing/rust/version
+++ /dev/null
@@ -1 +0,0 @@
-1.56.0 0