diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a218dc6..dbc8586 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -33,3 +33,48 @@ jobs:
 
       - name: Format check
         run: cargo fmt --check -p pathotypr-core 2>/dev/null || true
+
+  # The core job never builds the desktop backend, so nothing used to compile
+  # reqwest, the HTTP client or the TLS stack on a pull request.
+  gui:
+    name: GUI (Linux)
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: dtolnay/rust-toolchain@stable
+
+      # cmake for pathotypr-core; the rest is the GTK and WebKit stack the
+      # Tauri backend links against, matching what release.yml installs.
+      - name: Install build dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y \
+            cmake \
+            pkg-config \
+            libgtk-3-dev \
+            libwebkit2gtk-4.1-dev \
+            libayatana-appindicator3-dev \
+            librsvg2-dev
+
+      - name: Rust cache
+        uses: Swatinem/rust-cache@v2
+
+      - name: Check (gui)
+        run: cargo check -p pathotypr-gui
+
+      # reqwest is pinned to rustls so the Linux build carries no OpenSSL. A
+      # dependency bump could quietly pull native-tls back in, and openssl
+      # with it, without anything else here noticing.
+      - name: Assert the Linux build carries no OpenSSL
+        shell: bash
+        run: |
+          set -euo pipefail
+          tree=$(cargo tree -p pathotypr-gui \
+            --target x86_64-unknown-linux-gnu --edges normal --prefix none)
+          if grep -qE '^(openssl|native-tls) v' <<<"$tree"; then
+            echo "::error::native-tls or openssl is back in the Linux dependency graph"
+            grep -E '^(openssl|native-tls) v' <<<"$tree" | sort -u
+            exit 1
+          fi
+          echo "No openssl and no native-tls in the Linux dependency graph."
diff --git a/Cargo.lock b/Cargo.lock
index a2a038d..c27cf9b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -511,6 +511,23 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
+[[package]]
+name = "cfg_aliases"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f079e83a288787bcd14a6aea84cee5c87a67c5a3e660c30f557a3d24761b3527"
+
+[[package]]
+name = "chacha20"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d524456ba66e72eb8b115ff89e01e497f8e6d11d78b70b1aa13c0fbd97540a81"
+dependencies = [
+ "cfg-if",
+ "cpufeatures 0.3.0",
+ "rand_core 0.10.1",
+]
+
 [[package]]
 name = "chrono"
 version = "0.4.44"
@@ -681,7 +698,7 @@ dependencies = [
  "bitflags 2.11.0",
  "core-foundation 0.10.1",
  "core-graphics-types",
- "foreign-types 0.5.0",
+ "foreign-types",
  "libc",
 ]
 
@@ -705,6 +722,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "cpufeatures"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b2a41393f66f16b0823bb79094d54ac5fbd34ab292ddafb9a0456ac9f87d201"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crc32fast"
 version = "1.5.0"
@@ -1294,15 +1320,6 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77ce24cb58228fbb8aa041425bb1050850ac19177686ea6e0f41a70416f56fdb"
 
-[[package]]
-name = "foreign-types"
-version = "0.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f6f339eb8adc052cd2ca78910fda869aefa38d22d5cb648e6485e4d3fc06f3b1"
-dependencies = [
- "foreign-types-shared 0.1.1",
-]
-
 [[package]]
 name = "foreign-types"
 version = "0.5.0"
@@ -1310,7 +1327,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d737d9aa519fb7b749cbc3b962edcf310a8dd1f4b67c91c4f83975dbdd17d965"
 dependencies = [
  "foreign-types-macros",
- "foreign-types-shared 0.3.1",
+ "foreign-types-shared",
 ]
 
 [[package]]
@@ -1324,12 +1341,6 @@ dependencies = [
  "syn 2.0.117",
 ]
 
-[[package]]
-name = "foreign-types-shared"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "00b0228411908ca8685dba7fc2cdd70ec9990a6e753e89b6ac91a84c40fbaf4b"
-
 [[package]]
 name = "foreign-types-shared"
 version = "0.3.1"
@@ -1562,8 +1573,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ff2abc00be7fca6ebc474524697ae276ad847ad0a6b3faa4bcb027e9a4614ad0"
 dependencies = [
  "cfg-if",
+ "js-sys",
  "libc",
  "wasi 0.11.1+wasi-snapshot-preview1",
+ "wasm-bindgen",
 ]
 
 [[package]]
@@ -1585,10 +1598,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0de51e6874e94e7bf76d726fc5d13ba782deca734ff60d5bb2fb2607c7406555"
 dependencies = [
  "cfg-if",
+ "js-sys",
  "libc",
  "r-efi 6.0.0",
+ "rand_core 0.10.1",
  "wasip2",
  "wasip3",
+ "wasm-bindgen",
 ]
 
 [[package]]
@@ -1907,28 +1923,13 @@ dependencies = [
  "hyper",
  "hyper-util",
  "rustls",
+ "rustls-native-certs",
  "rustls-pki-types",
  "tokio",
  "tokio-rustls",
  "tower-service",
 ]
 
-[[package]]
-name = "hyper-tls"
-version = "0.6.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70206fc6890eaca9fde8a0bf71caa2ddfc9fe045ac9e5c70df101a7dbde866e0"
-dependencies = [
- "bytes",
- "http-body-util",
- "hyper",
- "hyper-util",
- "native-tls",
- "tokio",
- "tokio-native-tls",
- "tower-service",
-]
-
 [[package]]
 name = "hyper-util"
 version = "0.1.20"
@@ -2481,6 +2482,12 @@ version = "0.4.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
 
+[[package]]
+name = "lru-slab"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "112b39cec0b298b6c1999fee3e31427f74f676e4cb9879ed1a121b43661a4154"
+
 [[package]]
 name = "mac"
 version = "0.1.1"
@@ -2637,23 +2644,6 @@ dependencies = [
  "typenum",
 ]
 
-[[package]]
-name = "native-tls"
-version = "0.2.18"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "465500e14ea162429d264d44189adc38b199b62b1c21eea9f69e4b73cb03bbf2"
-dependencies = [
- "libc",
- "log",
- "openssl",
- "openssl-probe",
- "openssl-sys",
- "schannel",
- "security-framework",
- "security-framework-sys",
- "tempfile",
-]
-
 [[package]]
 name = "ndarray"
 version = "0.16.1"
@@ -2959,50 +2949,12 @@ version = "11.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d6790f58c7ff633d8771f42965289203411a5e5c68388703c06e14f24770b41e"
 
-[[package]]
-name = "openssl"
-version = "0.10.76"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "951c002c75e16ea2c65b8c7e4d3d51d5530d8dfa7d060b4776828c88cfb18ecf"
-dependencies = [
- "bitflags 2.11.0",
- "cfg-if",
- "foreign-types 0.3.2",
- "libc",
- "once_cell",
- "openssl-macros",
- "openssl-sys",
-]
-
-[[package]]
-name = "openssl-macros"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.117",
-]
-
 [[package]]
 name = "openssl-probe"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7c87def4c32ab89d880effc9e097653c8da5d6ef28e6b539d313baaacfbafcbe"
 
-[[package]]
-name = "openssl-sys"
-version = "0.9.112"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57d55af3b3e226502be1526dfdba67ab0e9c96fc293004e79576b2b9edb0dbdb"
-dependencies = [
- "cc",
- "libc",
- "pkg-config",
- "vcpkg",
-]
-
 [[package]]
 name = "option-ext"
 version = "0.2.0"
@@ -3528,6 +3480,62 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "quinn"
+version = "0.11.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c1a41e437b6bbd489372cd4971de128e85c855f56c57f283d20ff016cf7c0a8"
+dependencies = [
+ "bytes",
+ "cfg_aliases",
+ "pin-project-lite",
+ "quinn-proto",
+ "quinn-udp",
+ "rustc-hash",
+ "rustls",
+ "socket2",
+ "thiserror 2.0.18",
+ "tokio",
+ "tracing",
+ "web-time",
+]
+
+[[package]]
+name = "quinn-proto"
+version = "0.11.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f4bfc015262b9df63c8845072ce59068853ff5872180c2ce2f13038b970e560"
+dependencies = [
+ "bytes",
+ "getrandom 0.4.2",
+ "lru-slab",
+ "rand 0.10.2",
+ "rand_pcg 0.10.2",
+ "ring",
+ "rustc-hash",
+ "rustls",
+ "rustls-pki-types",
+ "slab",
+ "thiserror 2.0.18",
+ "tinyvec",
+ "tracing",
+ "web-time",
+]
+
+[[package]]
+name = "quinn-udp"
+version = "0.5.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "35a133f956daabe89a61a685c2649f13d82d5aa4bd5d12d1277e1072a21c0694"
+dependencies = [
+ "cfg_aliases",
+ "libc",
+ "once_cell",
+ "socket2",
+ "tracing",
+ "windows-sys 0.52.0",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.45"
@@ -3560,7 +3568,7 @@ dependencies = [
  "rand_chacha 0.2.2",
  "rand_core 0.5.1",
  "rand_hc",
- "rand_pcg",
+ "rand_pcg 0.2.1",
 ]
 
 [[package]]
@@ -3574,6 +3582,17 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "rand"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7f5fa3a058cd35567ef9bfa5e75732bee0f9e4c55fa90477bef2dfcdbc4be80"
+dependencies = [
+ "chacha20",
+ "getrandom 0.4.2",
+ "rand_core 0.10.1",
+]
+
 [[package]]
 name = "rand_chacha"
 version = "0.2.2"
@@ -3612,6 +3631,12 @@ dependencies = [
  "getrandom 0.2.17",
 ]
 
+[[package]]
+name = "rand_core"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63b8176103e19a2643978565ca18b50549f6101881c443590420e4dc998a3c69"
+
 [[package]]
 name = "rand_distr"
 version = "0.4.3"
@@ -3640,6 +3665,15 @@ dependencies = [
  "rand_core 0.5.1",
 ]
 
+[[package]]
+name = "rand_pcg"
+version = "0.10.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "caa0f4137e1c0a72f4c651489402276c8e8e1cf081f3b0ba156d2cbeef09e86a"
+dependencies = [
+ "rand_core 0.10.1",
+]
+
 [[package]]
 name = "raw-window-handle"
 version = "0.6.2"
@@ -3758,21 +3792,22 @@ dependencies = [
  "http-body-util",
  "hyper",
  "hyper-rustls",
- "hyper-tls",
  "hyper-util",
  "js-sys",
  "log",
  "mime",
- "native-tls",
  "percent-encoding",
  "pin-project-lite",
+ "quinn",
+ "rustls",
+ "rustls-native-certs",
  "rustls-pki-types",
  "serde",
  "serde_json",
  "serde_urlencoded",
  "sync_wrapper",
  "tokio",
- "tokio-native-tls",
+ "tokio-rustls",
  "tokio-util",
  "tower",
  "tower-http",
@@ -3918,18 +3953,32 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "758025cb5fccfd3bc2fd74708fd4682be41d99e5dff73c377c0646c6012c73a4"
 dependencies = [
  "once_cell",
+ "ring",
  "rustls-pki-types",
  "rustls-webpki",
  "subtle",
  "zeroize",
 ]
 
+[[package]]
+name = "rustls-native-certs"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dab5152771c58876a2146916e53e35057e1a4dfa2b9df0f0305b07f611fdea4d"
+dependencies = [
+ "openssl-probe",
+ "rustls-pki-types",
+ "schannel",
+ "security-framework",
+]
+
 [[package]]
 name = "rustls-pki-types"
 version = "1.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "be040f8b0a225e40375822a563fa9524378b9d63112f53e19ffff34df5d33fdd"
 dependencies = [
+ "web-time",
  "zeroize",
 ]
 
@@ -4302,7 +4351,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a7507d819769d01a365ab707794a4084392c824f54a7a6a7862f8c3d0892b283"
 dependencies = [
  "cfg-if",
- "cpufeatures",
+ "cpufeatures 0.2.17",
  "digest",
 ]
 
@@ -5049,6 +5098,21 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "tinyvec"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bb4ebadaa0af04fab11ae01eb5f9fdb5f9c5b875506e210e71c07873528baa7f"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
+
 [[package]]
 name = "tokio"
 version = "1.50.0"
@@ -5075,16 +5139,6 @@ dependencies = [
  "syn 2.0.117",
 ]
 
-[[package]]
-name = "tokio-native-tls"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bbae76ab933c85776efabc971569dd6119c580d8f5d448769dec1764bf796ef2"
-dependencies = [
- "native-tls",
- "tokio",
-]
-
 [[package]]
 name = "tokio-rustls"
 version = "0.26.4"
@@ -5460,12 +5514,6 @@ dependencies = [
  "wasm-bindgen",
 ]
 
-[[package]]
-name = "vcpkg"
-version = "0.2.15"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
-
 [[package]]
 name = "vec_map"
 version = "0.8.2"
diff --git a/src-tauri/Cargo.toml b/src-tauri/Cargo.toml
index ab4546c..b0fe743 100644
--- a/src-tauri/Cargo.toml
+++ b/src-tauri/Cargo.toml
@@ -15,7 +15,17 @@ tauri-plugin-dialog = "2"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tokio = { version = "1", features = ["rt-multi-thread", "macros"] }
-reqwest = { version = "0.12", features = ["stream"] }
+# rustls instead of the default native-tls: on Linux native-tls binds the
+# system OpenSSL, which put a whole C TLS stack in the graph just to fetch
+# files over HTTPS. Roots come from the system store, so users behind an
+# institutional proxy with a private CA keep working.
+reqwest = { version = "0.12", default-features = false, features = [
+    "stream",
+    "rustls-tls-native-roots",
+    "charset",
+    "http2",
+    "system-proxy",
+] }
 tokio-util = { version = "0.7", features = ["io"] }
 futures-util = "0.3"
 log = "0.4"