diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 84c6df1..d235452 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -25,9 +25,6 @@ jobs:
       - name: Unit tests
         # same reason as integration tests: nimble exits with code 0 even on failure.
         run: |
-          cmake -B vendor/libplum/build -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF vendor/libplum
-          cmake --build vendor/libplum/build
-          cp vendor/libplum/build/libplum.a vendor/libplum/libplum.a
           nim c -o:tests/test_plum tests/test_plum.nim
           ./tests/test_plum
 
diff --git a/libplum.nimble b/libplum.nimble
index ab798d8..6744764 100644
--- a/libplum.nimble
+++ b/libplum.nimble
@@ -13,20 +13,10 @@ requires "nim >= 1.6.0",
          "chronos >= 4.2.0 & < 5.0.0",
          "unittest2"
 
-proc compileStaticLibraries() =
-  withDir "vendor/libplum":
-    exec("cmake -B build -DCMAKE_BUILD_TYPE=Release -DBUILD_SHARED_LIBS=OFF")
-    exec("cmake --build build")
-    cpFile("build/libplum.a", "libplum.a")
-
 task format, "format Nim code using nph":
   exec "nph libplum/ tests/"
 
-task buildBundledLibs, "build bundled libraries":
-  compileStaticLibraries()
-
 task test, "run tests":
-  compileStaticLibraries()
   exec("nimble setup")
   exec("nim c -o:tests/test_plum tests/test_plum.nim")
   exec("./tests/test_plum")
@@ -40,6 +30,3 @@ task testIntegration, "run miniupnpd integration tests in Docker / Podman":
   exec(docker & " run --rm --cap-add=NET_ADMIN -e TEST_MINIUPNP_PCP=1" & flags & " " & packageName)
   exec(docker & " run --rm --cap-add=NET_ADMIN -e TEST_MINIUPNP_UPNP=1" & flags & " " & packageName)
   exec(docker & " run --rm --cap-add=NET_ADMIN -e TEST_MINIUPNP_NATPMP=1" & flags & " " & packageName)
-
-before install:
-  compileStaticLibraries()
diff --git a/libplum/libplum.nim b/libplum/libplum.nim
index 9c3457e..d0ce609 100644
--- a/libplum/libplum.nim
+++ b/libplum/libplum.nim
@@ -6,21 +6,37 @@
 # This file may not be copied, modified, or distributed except according to
 # those terms.
 
-import std/[os, strutils]
+import std/[os, sequtils, strutils]
 
 const
   rootPath = currentSourcePath.parentDir().parentDir().replace('\\', '/')
   libplumPath = rootPath & "/vendor/libplum"
   includePath = libplumPath & "/include/plum"
-  libraryPath = libplumPath & "/libplum.a"
-{.passc: "-I" & includePath & " -DPLUM_STATIC".}
-{.passl: libraryPath.}
+  srcPath = libplumPath & "/src"
+
+  includes = @["-I" & includePath, "-I" & srcPath]
+
+  defs = @["-DPLUM_STATIC", "-DPLUM_EXPORTS", "-DRELEASE=1", "-D_GNU_SOURCE"]
+
+  pdefs =
+    when defined(windows):
+      @["-DWIN32_LEAN_AND_MEAN"]
+    else:
+      @[]
+
+  flags* = (includes & defs & pdefs).mapIt(it.quoteShell()).join(" ")
+
+{.localPassC: flags.}
 
 when defined(windows):
   {.passl: "-lws2_32 -liphlpapi -lbcrypt".}
 else:
   {.passl: "-lpthread".}
 
+{.compile(rootPath & "/libplum_units.c", flags).}
+{.compile(srcPath & "/http.c", flags).}
+{.compile(srcPath & "/upnp.c", flags).}
+
 const
   PLUM_ERR_SUCCESS* = cint(0)
   PLUM_ERR_INVALID* = cint(-1)
diff --git a/libplum/plum.nim b/libplum/plum.nim
index ca14cf7..65b3aad 100644
--- a/libplum/plum.nim
+++ b/libplum/plum.nim
@@ -10,7 +10,9 @@ import std/atomics
 import chronos
 import chronos/threadsync
 import results
-import ./libplum
+import libplum
+
+{.localPassC: libplum.flags.}
 
 # libplum declares some parameters as `const T*` in C (read-only pointer).
 # Nim has no equivalent, so the generated C code drops the `const`, causing
diff --git a/libplum_units.c b/libplum_units.c
new file mode 100644
index 0000000..0099e7d
--- /dev/null
+++ b/libplum_units.c
@@ -0,0 +1,22 @@
+// Copyright (c) 2026 Status Research & Development GmbH
+// Licensed under either of
+//  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+//  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+// at your option.
+// This file may not be copied, modified, or distributed except according to
+// those terms.
+
+#include "./vendor/libplum/src/addr.c"
+#include "./vendor/libplum/src/client.c"
+#include "./vendor/libplum/src/dummytls.c"
+#include "./vendor/libplum/src/log.c"
+#include "./vendor/libplum/src/natpmp.c"
+#include "./vendor/libplum/src/net.c"
+#include "./vendor/libplum/src/noprotocol.c"
+#include "./vendor/libplum/src/pcp.c"
+#include "./vendor/libplum/src/plum.c"
+#include "./vendor/libplum/src/random.c"
+#include "./vendor/libplum/src/tcp.c"
+#include "./vendor/libplum/src/timestamp.c"
+#include "./vendor/libplum/src/udp.c"
+#include "./vendor/libplum/src/util.c"
diff --git a/tests/Dockerfile b/tests/Dockerfile
index e4b21ef..9180a6c 100644
--- a/tests/Dockerfile
+++ b/tests/Dockerfile
@@ -1,7 +1,7 @@
 FROM ubuntu:24.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    cmake gcc make git curl ca-certificates xz-utils \
+    gcc make git curl ca-certificates xz-utils \
     libc-dev \
     iproute2 \
     && rm -rf /var/lib/apt/lists/*
@@ -34,19 +34,11 @@ RUN curl -fsSL "https://nim-lang.org/download/nim-${NIM_VERSION}-linux_x64.tar.x
 # Install nim deps (cached layer)
 WORKDIR /app
 COPY libplum.nimble .
+COPY libplum_units.c .
 COPY libplum/ libplum/
 COPY vendor/ vendor/
 RUN nimble setup -y
 
-# Build libplum static library
-RUN rm -rf vendor/libplum/build && \
-    cmake -B vendor/libplum/build \
-    -DCMAKE_BUILD_TYPE=Release \
-    -DBUILD_SHARED_LIBS=OFF \
-    vendor/libplum && \
-    cmake --build vendor/libplum/build && \
-    cp vendor/libplum/build/libplum.a vendor/libplum/libplum.a
-
 # Compile test binaries (protocol x memory manager)
 COPY tests/ tests/
 RUN nim c -d:miniupnp_protocol=pcp   --mm:orc  --threads:on -o:tests/test_pcp_orc   tests/test_plum.nim && \