diff --git a/Cargo.lock b/Cargo.lock
index f2fd9f4..df58941 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,6 +3,15 @@ name = "ascii"
 version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "base64"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "safemem 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "base64"
 version = "0.10.0"
@@ -11,11 +20,6 @@ dependencies = [
  "byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "bitflags"
-version = "1.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "byteorder"
 version = "1.2.7"
@@ -36,14 +40,6 @@ name = "chunked_transfer"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "cloudabi"
-version = "0.0.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "cookie"
 version = "0.11.0"
@@ -53,23 +49,6 @@ dependencies = [
  "url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "core-foundation"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "core-foundation-sys 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "core-foundation-sys"
-version = "0.5.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "encoding"
 version = "0.2.33"
@@ -127,33 +106,6 @@ name = "encoding_index_tests"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "foreign-types"
-version = "0.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "foreign-types-shared"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "fuchsia-zircon"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "fuchsia-zircon-sys"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "idna"
 version = "0.1.5"
@@ -192,62 +144,11 @@ name = "matches"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "native-tls"
-version = "0.2.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "openssl 0.10.15 (registry+https://github.com/rust-lang/crates.io-index)",
- "openssl-probe 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "openssl-sys 0.9.39 (registry+https://github.com/rust-lang/crates.io-index)",
- "schannel 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "security-framework 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "security-framework-sys 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "tempfile 3.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "openssl"
-version = "0.10.15"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "openssl-sys 0.9.39 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "openssl-probe"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "openssl-sys"
-version = "0.9.39"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "vcpkg 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "percent-encoding"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "pkg-config"
-version = "0.3.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "qstring"
 version = "0.6.0"
@@ -256,90 +157,33 @@ dependencies = [
  "percent-encoding 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "rand"
-version = "0.6.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_chacha 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_pcg 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_chacha"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_core"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "rand_hc"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_isaac"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_pcg"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "rand_xorshift"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "rand_core 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "redox_syscall"
 version = "0.1.43"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "remove_dir_all"
-version = "0.5.1"
+name = "ring"
+version = "0.13.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
+ "untrusted 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
-name = "rustc_version"
-version = "0.2.3"
+name = "rustls"
+version = "0.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "semver 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "base64 0.9.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ring 0.13.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sct 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "untrusted 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webpki 0.18.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -348,47 +192,19 @@ version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "schannel"
-version = "0.1.14"
+name = "safemem"
+version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
 
 [[package]]
-name = "security-framework"
-version = "0.2.1"
+name = "sct"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "core-foundation 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "core-foundation-sys 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "security-framework-sys 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ring 0.13.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "untrusted 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "security-framework-sys"
-version = "0.2.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "core-foundation-sys 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "semver"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "serde"
 version = "1.0.80"
@@ -404,19 +220,6 @@ dependencies = [
  "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "tempfile"
-version = "3.0.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "redox_syscall 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)",
- "remove_dir_all 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "time"
 version = "0.1.40"
@@ -440,6 +243,11 @@ name = "unicode-normalization"
 version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "untrusted"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "ureq"
 version = "0.7.0"
@@ -450,10 +258,12 @@ dependencies = [
  "cookie 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "encoding 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "native-tls 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "qstring 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustls 0.13.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.33 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webpki 0.18.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webpki-roots 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -467,9 +277,22 @@ dependencies = [
 ]
 
 [[package]]
-name = "vcpkg"
-version = "0.2.6"
+name = "webpki"
+version = "0.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "ring 0.13.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "untrusted 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "webpki-roots"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "untrusted 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "webpki 0.18.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "winapi"
@@ -493,15 +316,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [metadata]
 "checksum ascii 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a5fc969a8ce2c9c0c4b0429bb8431544f6658283c8326ba5ff8c762b75369335"
 "checksum base64 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "621fc7ecb8008f86d7fb9b95356cd692ce9514b80a86d85b397f32a22da7b9e2"
-"checksum bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "228047a76f468627ca71776ecdebd732a3423081fcf5125585bcd7c49886ce12"
+"checksum base64 0.9.3 (registry+https://github.com/rust-lang/crates.io-index)" = "489d6c0ed21b11d038c31b6ceccca973e65d73ba3bd8ecb9a2babf5546164643"
 "checksum byteorder 1.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "94f88df23a25417badc922ab0f5716cc1330e87f71ddd9203b3a3ccd9cedf75d"
 "checksum cc 1.0.25 (registry+https://github.com/rust-lang/crates.io-index)" = "f159dfd43363c4d08055a07703eb7a3406b0dac4d0584d96965a3262db3c9d16"
 "checksum cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "082bb9b28e00d3c9d39cc03e64ce4cea0f1bb9b3fde493f0cbc008472d22bdf4"
 "checksum chunked_transfer 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "498d20a7aaf62625b9bf26e637cf7736417cde1d0c99f1d04d1170229a85cf87"
-"checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
 "checksum cookie 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1465f8134efa296b4c19db34d909637cb2bf0f7aaf21299e23e18fa29ac557cf"
-"checksum core-foundation 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "286e0b41c3a20da26536c6000a280585d519fd07b3956b43aed8a79e9edce980"
-"checksum core-foundation-sys 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "716c271e8613ace48344f723b60b900a93150271e5be206212d052bbc0883efa"
 "checksum encoding 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)" = "6b0d943856b990d12d3b55b359144ff341533e516d94098b1d3fc1ac666d36ec"
 "checksum encoding-index-japanese 1.20141219.5 (registry+https://github.com/rust-lang/crates.io-index)" = "04e8b2ff42e9a05335dbf8b5c6f7567e5591d0d916ccef4e0b1710d32a0d0c91"
 "checksum encoding-index-korean 1.20141219.5 (registry+https://github.com/rust-lang/crates.io-index)" = "4dc33fb8e6bcba213fe2f14275f0963fd16f0a02c878e3095ecfdf5bee529d81"
@@ -509,47 +329,29 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum encoding-index-singlebyte 1.20141219.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3351d5acffb224af9ca265f435b859c7c01537c0849754d3db3fdf2bfe2ae84a"
 "checksum encoding-index-tradchinese 1.20141219.5 (registry+https://github.com/rust-lang/crates.io-index)" = "fd0e20d5688ce3cab59eb3ef3a2083a5c77bf496cb798dc6fcdb75f323890c18"
 "checksum encoding_index_tests 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "a246d82be1c9d791c5dfde9a2bd045fc3cbba3fa2b11ad558f27d01712f00569"
-"checksum foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
-"checksum foreign-types-shared 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
-"checksum fuchsia-zircon 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2e9763c69ebaae630ba35f74888db465e49e259ba1bc0eda7d06f4a067615d82"
-"checksum fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3dcaa9ae7725d12cdb85b3ad99a434db70b468c09ded17e012d86b5c1010f7a7"
 "checksum idna 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "38f09e0f0b1fb55fdee1f17470ad800da77af5186a1a76c026b679358b7e844e"
 "checksum itoa 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)" = "1306f3464951f30e30d12373d31c79fbd52d236e5e896fd92f96ec7babbbe60b"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum libc 0.2.44 (registry+https://github.com/rust-lang/crates.io-index)" = "10923947f84a519a45c8fefb7dd1b3e8c08747993381adee176d7a82b4195311"
 "checksum log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c84ec4b527950aa83a329754b01dbe3f58361d1c5efacd1f6d68c494d08a17c6"
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diff --git a/Cargo.toml b/Cargo.toml
index bbca4b8..40e5c36 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,7 +14,7 @@ edition = "2018"
 default = ["tls"]
 json = ["serde_json"]
 charset = ["encoding"]
-tls = ["native-tls"]
+tls = ["rustls", "webpki", "webpki-roots"]
 
 [dependencies]
 ascii = "0.9"
@@ -24,6 +24,8 @@ cookie = { version = "0.11", features = ["percent-encode"] }
 lazy_static = "1"
 qstring = "0.6"
 url = "1"
-native-tls = { version = "0.2", optional = true }
+rustls = { version = "0.13", optional = true }
+webpki = { version = "0.18", optional = true }
+webpki-roots = { version = "0.15", optional = true }
 serde_json = { version = "1", optional = true }
 encoding = { version = "0.2", optional = true }
diff --git a/README.md b/README.md
index 054dd7c..fd8bb24 100644
--- a/README.md
+++ b/README.md
@@ -65,7 +65,7 @@ dependencies, this library might change.
 - [ ] Forms with application/x-www-form-urlencoded
 - [ ] multipart/form-data
 - [ ] Expect 100-continue
-- [ ] Use `rustls` when [ring with versioned asm symbols](https://github.com/briansmith/ring/pull/619) is released.
+- [x] Use `rustls` when [ring with versioned asm symbols](https://github.com/briansmith/ring/pull/619) is released. (PR is not resolved, but most implementations have settled on 0.13)
 
 ## License (MIT)
 
diff --git a/src/error.rs b/src/error.rs
index 26d3aad..8c5cbed 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -1,12 +1,5 @@
 use std::io::Error as IoError;
 
-#[cfg(feature = "tls")]
-use native_tls::Error as TlsError;
-#[cfg(feature = "tls")]
-use native_tls::HandshakeError;
-#[cfg(feature = "tls")]
-use std::net::TcpStream;
-
 /// Errors that are translated to ["synthetic" responses](struct.Response.html#method.synthetic).
 #[derive(Debug)]
 pub enum Error {
@@ -26,12 +19,6 @@ pub enum Error {
     BadHeader,
     /// Some unspecified `std::io::Error`. Synthetic error `500`.
     Io(IoError),
-    /// Some unspecified TLS error. Synthetic error `400`.
-    #[cfg(feature = "tls")]
-    Tls(TlsError),
-    /// Some unspecified TLS handshake error. Synthetic error `500`.
-    #[cfg(feature = "tls")]
-    TlsHandshake(HandshakeError<TcpStream>),
 }
 
 impl Error {
@@ -46,10 +33,6 @@ impl Error {
             Error::BadStatus => 500,
             Error::BadHeader => 500,
             Error::Io(_) => 500,
-            #[cfg(feature = "tls")]
-            Error::Tls(_) => 400,
-            #[cfg(feature = "tls")]
-            Error::TlsHandshake(_) => 500,
         }
     }
 
@@ -64,10 +47,6 @@ impl Error {
             Error::BadStatus => "Bad Status",
             Error::BadHeader => "Bad Header",
             Error::Io(_) => "Network Error",
-            #[cfg(feature = "tls")]
-            Error::Tls(_) => "TLS Error",
-            #[cfg(feature = "tls")]
-            Error::TlsHandshake(_) => "TLS Handshake Error",
         }
     }
 
@@ -82,10 +61,6 @@ impl Error {
             Error::BadStatus => "Bad Status".to_string(),
             Error::BadHeader => "Bad Header".to_string(),
             Error::Io(ioe) => format!("Network Error: {}", ioe),
-            #[cfg(feature = "tls")]
-            Error::Tls(tls) => format!("TLS Error: {}", tls),
-            #[cfg(feature = "tls")]
-            Error::TlsHandshake(he) => format!("TLS Handshake Error: {}", he),
         }
     }
 }
@@ -95,17 +70,3 @@ impl From<IoError> for Error {
         Error::Io(err)
     }
 }
-
-#[cfg(feature = "tls")]
-impl From<TlsError> for Error {
-    fn from(err: TlsError) -> Error {
-        Error::Tls(err)
-    }
-}
-
-#[cfg(feature = "tls")]
-impl From<HandshakeError<TcpStream>> for Error {
-    fn from(err: HandshakeError<TcpStream>) -> Error {
-        Error::TlsHandshake(err)
-    }
-}
diff --git a/src/stream.rs b/src/stream.rs
index 7c654dd..c1091bd 100644
--- a/src/stream.rs
+++ b/src/stream.rs
@@ -1,18 +1,17 @@
 use crate::agent::Unit;
 use crate::error::Error;
+use lazy_static::lazy_static;
 use std::io::{Cursor, Read, Result as IoResult, Write};
 use std::net::SocketAddr;
 use std::net::TcpStream;
 use std::net::ToSocketAddrs;
 use std::time::Duration;
 
-#[cfg(feature = "tls")]
-use native_tls::TlsStream;
-
+#[allow(clippy::large_enum_variant)]
 pub enum Stream {
     Http(TcpStream),
     #[cfg(feature = "tls")]
-    Https(TlsStream<TcpStream>),
+    Https(rustls::StreamOwned<rustls::ClientSession, TcpStream>),
     Cursor(Cursor<Vec<u8>>),
     #[cfg(test)]
     Test(Box<dyn Read + Send>, Vec<u8>),
@@ -100,14 +99,27 @@ pub fn connect_http(unit: &Unit) -> Result<Stream, Error> {
 
 #[cfg(feature = "tls")]
 pub fn connect_https(unit: &Unit) -> Result<Stream, Error> {
-    use native_tls::TlsConnector;
+    use std::sync::Arc;
+
+    lazy_static! {
+        static ref TLS_CONF: Arc<rustls::ClientConfig> = {
+            let mut config = rustls::ClientConfig::new();
+            config
+                .root_store
+                .add_server_trust_anchors(&webpki_roots::TLS_SERVER_ROOTS);
+            Arc::new(config)
+        };
+    }
 
     let hostname = unit.url.host_str().unwrap();
     let port = unit.url.port().unwrap_or(443);
 
-    let socket = connect_host(unit, hostname, port)?;
-    let connector = TlsConnector::builder().build()?;
-    let stream = connector.connect(hostname, socket)?;
+    let sni = webpki::DNSNameRef::try_from_ascii_str(hostname).unwrap();
+    let sess = rustls::ClientSession::new(&*TLS_CONF, sni);
+
+    let sock = connect_host(unit, hostname, port)?;
+
+    let stream = rustls::StreamOwned::new(sess, sock);
 
     Ok(Stream::Https(stream))
 }