diff --git a/README.md b/README.md
index 5a068ab..80ad4b2 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,9 @@ acceleration where the underlying algorithms admit it.
 
 ## Status
 
-Early development. The public API and ABI are unstable until 1.0.
+**1.0.0** — public API and ABI are stable. SONAME is `libksuid.so.1`;
+subsequent 1.x releases stay binary-compatible (semver). A breaking
+ABI change would require a 2.0 with a new SONAME.
 
 ## Goals
 
@@ -68,9 +70,14 @@ A release build on x86_64 produces (post-`strip --strip-unneeded`):
 
 | Artifact            | Bytes  |
 | :------------------ | -----: |
-| libksuid.so.0.1.0   | 18 560 |
-| libksuid.a          | 24 804 |
-| ksuid-gen (CLI)     | 27 464 |
+| libksuid.so.1.0.0   | 26 752 |
+| libksuid.a          | 35 212 |
+| ksuid-gen (CLI)     | 22 920 |
+
+The bulk-encode AVX2 kernel from `libksuid/encode_avx2.c` accounts for
+roughly 8 KB of the shared-library size; non-AVX2 hosts compile and
+link the kernel but never call into it, so the CPUID-gated dispatch
+adds no runtime cost to those targets.
 
 The shared library has zero runtime dependencies beyond the C library
 and, on Windows, `bcrypt.lib`.
diff --git a/meson.build b/meson.build
index f6231bf..6843ce1 100644
--- a/meson.build
+++ b/meson.build
@@ -1,5 +1,5 @@
 project('libksuid', 'c',
-  version : '0.1.0',
+  version : '1.0.0',
   license : 'LGPL-3.0-or-later AND MIT',
   meson_version : '>=1.1.0',
   default_options : [
@@ -237,7 +237,10 @@ ksuid_lib = both_libraries('ksuid', core_sources,
   dependencies        : extra_link_deps,
   link_whole          : avx2_lib_dep,
   version             : meson.project_version(),
-  soversion           : '0',
+  # soversion tracks semver major: a major bump means a binary-
+  # incompatible ABI break and the SONAME flips with it. 1.0 is the
+  # first stable ABI commitment.
+  soversion           : '1',
   install             : true,
 )
 
diff --git a/tests/test_smoke.c b/tests/test_smoke.c
index a1259d0..f2d9de4 100644
--- a/tests/test_smoke.c
+++ b/tests/test_smoke.c
@@ -88,10 +88,10 @@ test_version_macros_are_consistent (void)
    *
    * When you bump meson.build's project version you MUST update
    * these four asserts in the same commit. */
-  ASSERT_EQ_INT (KSUID_VERSION_MAJOR, 0);
-  ASSERT_EQ_INT (KSUID_VERSION_MINOR, 1);
+  ASSERT_EQ_INT (KSUID_VERSION_MAJOR, 1);
+  ASSERT_EQ_INT (KSUID_VERSION_MINOR, 0);
   ASSERT_EQ_INT (KSUID_VERSION_PATCH, 0);
-  ASSERT_EQ_STR (KSUID_VERSION_STRING, "0.1.0");
+  ASSERT_EQ_STR (KSUID_VERSION_STRING, "1.0.0");
 
   /* The composite KSUID_VERSION must equal the documented
    * (MAJOR << 16) | (MINOR << 8) | PATCH layout for `#if