cloaked_req

cloaked_req is a Req adapter backed by Rust wreq, focused on browser impersonation and performance.

Goal

Keep Req ergonomics while swapping transport to Rust wreq for impersonation and fingerprint-sensitive requests.

Installation

def deps do
  [
    {:cloaked_req, "~> 0.3.0"}
  ]
end

Usage

Use as a Req adapter:

request =
  Req.new(url: "https://tls.peet.ws/api/all")
  |> CloakedReq.attach(impersonate: :chrome_136)

response = Req.get!(request)

Set impersonation later on an existing request:

request =
  Req.new(url: "https://example.com")
  |> CloakedReq.impersonate(:firefox_136)

Adapter Options

Option	Type	Default	Description
:impersonate	atom	nil	Browser profile (e.g. :chrome_136)
:cookie_jar	CookieJar.t()	nil	Automatic cookie persistence across requests
:insecure_skip_verify	boolean	false	Skip TLS certificate verification
:max_body_size	pos_integer | :unlimited	10 MB	Max response body size

Req's :receive_timeout (default 15s) is also respected.

Cookie Jar

Cookies are automatically stored from set-cookie response headers and sent with subsequent requests sharing the same jar. The jar uses PSL-based domain validation — it rejects cookies set on public suffixes and cross-origin domains.

jar = CloakedReq.CookieJar.new()

# Login — server sets session cookie
Req.new(url: "https://example.com/login")
|> CloakedReq.attach(impersonate: :chrome_136, cookie_jar: jar)
|> Req.post!(body: "user=admin&pass=secret")

# Dashboard — session cookie sent automatically
Req.new(url: "https://example.com/dashboard")
|> CloakedReq.attach(impersonate: :chrome_136, cookie_jar: jar)
|> Req.get!()

Impersonation Profiles

Profiles based on wreq-util 3.0.0-rc.10.

Chrome

:chrome_100, :chrome_101, :chrome_104, :chrome_105, :chrome_106, :chrome_107, :chrome_108, :chrome_109, :chrome_110, :chrome_114, :chrome_116, :chrome_117, :chrome_118, :chrome_119, :chrome_120, :chrome_123, :chrome_124, :chrome_126, :chrome_127, :chrome_128, :chrome_129, :chrome_130, :chrome_131, :chrome_132, :chrome_133, :chrome_134, :chrome_135, :chrome_136, :chrome_137, :chrome_138, :chrome_139, :chrome_140, :chrome_141, :chrome_142, :chrome_143, :chrome_144, :chrome_145

Edge

:edge_101, :edge_122, :edge_127, :edge_131, :edge_134, :edge_135, :edge_136, :edge_137, :edge_138, :edge_139, :edge_140, :edge_141, :edge_142, :edge_143, :edge_144, :edge_145

Opera

:opera_116, :opera_117, :opera_118, :opera_119

Firefox

:firefox_109, :firefox_117, :firefox_128, :firefox_133, :firefox_135, :firefox_private_135, :firefox_android_135, :firefox_136, :firefox_private_136, :firefox_139, :firefox_142, :firefox_143, :firefox_144, :firefox_145, :firefox_146, :firefox_147

Safari

:safari_16, :safari_18, :safari_ipad_18, :safari_26, :safari_ipad_26, :safari_ios_26

OkHttp

:okhttp_5

Limitations

• No HTTP/3 / QUIC — wreq supports HTTP/1.1 and HTTP/2 only. QUIC transport fingerprinting (JA4QUIC) is not available. If HTTP/3 fingerprinting is critical for your use case, consider a Go-based alternative like surf which supports HTTP/3 with full QUIC fingerprinting — though it would require a different integration approach (sidecar/Port rather than NIF).

Benchmark

50 sequential GET requests to a local HTTP server, 3 warmup rounds. Measures pure adapter overhead without network variance.

CLOAKED_REQ_BUILD=1 mix run bench/adapter_perf.exs

Run 1

Adapter	min	median	mean	p99	max
Req (Finch)	0.13 ms	0.14 ms	0.15 ms	0.34 ms	0.34 ms
CloakedReq (wreq NIF)	0.05 ms	0.06 ms	0.07 ms	0.17 ms	0.17 ms

CloakedReq median is 54.7 % faster than Req.

Run 2

Adapter	min	median	mean	p99	max
Req (Finch)	0.11 ms	0.15 ms	0.16 ms	0.36 ms	0.36 ms
CloakedReq (wreq NIF)	0.07 ms	0.08 ms	0.09 ms	0.24 ms	0.24 ms

CloakedReq median is 43.5 % faster than Req.

Run 3

Adapter	min	median	mean	p99	max
Req (Finch)	0.12 ms	0.14 ms	0.16 ms	0.35 ms	0.35 ms
CloakedReq (wreq NIF)	0.07 ms	0.09 ms	0.09 ms	0.25 ms	0.25 ms

CloakedReq median is 41.0 % faster than Req.