diff --git a/.llm/BETA_3_STDLIB_STABILIZATION.md b/.llm/BETA_3_STDLIB_STABILIZATION.md
index 7e550d1..17872fd 100644
--- a/.llm/BETA_3_STDLIB_STABILIZATION.md
+++ b/.llm/BETA_3_STDLIB_STABILIZATION.md
@@ -1,5 +1,11 @@
 # Beta 3 Standard Library Stabilization
 
+Release label: `1.0.0-beta.3`
+
+Release date: 2026-05-22
+
+Status: released beta standard-library stabilization slice.
+
 ## Scope
 
 This post-`1.0.0-beta.2` slice stabilizes the existing standard-library surface
diff --git a/README.md b/README.md
index a0e47df..5c36443 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ This repository is the canonical public monorepo for the language design,
 standard library source, compiler, runtime, examples, benchmarks, and technical
 documents.
 
-Current release: `1.0.0-beta.2`.
+Current release: `1.0.0-beta.3`.
 
 ## Repository Layout
 
@@ -24,10 +24,11 @@ scripts/        local release and document tooling
 
 ## Beta Scope
 
-`1.0.0-beta.2` keeps the `1.0.0-beta` language baseline, includes the
-`1.0.0-beta.1` tooling/install hardening slice, and adds the first
-runtime/resource foundation bundle. The language baseline supports practical
-local command-line programs and libraries with:
+`1.0.0-beta.3` keeps the `1.0.0-beta` language baseline, includes the
+`1.0.0-beta.1` tooling/install hardening slice, the `1.0.0-beta.2`
+runtime/resource foundation bundle, and the first standard-library
+stabilization bundle. The language baseline supports practical local
+command-line programs and libraries with:
 
 - modules, explicit imports, packages, and local workspaces
 - `new`, `check`, `fmt`, `test`, `doc`, and `build`
@@ -134,10 +135,10 @@ async IO, platform error codes, or stable handle ABI/layout. Directory creation
 is intentionally narrow and does not imply directory enumeration or recursive
 filesystem APIs.
 
-## Post-beta Mainline
+## 1.0.0-beta.3 Standard Library Stabilization
 
-Current `main` after `1.0.0-beta.2` has started the standard-library
-stabilization slice. It includes a generated standard-library API catalog and
+The `1.0.0-beta.3` release starts the standard-library stabilization slice. It
+adds a generated standard-library API catalog and
 `examples/projects/stdlib-composition`, a checked/tested/run-capable program
 that composes `std.fs`, `std.string`, `std.math`, and `std.io`.
 
diff --git a/compiler/Cargo.lock b/compiler/Cargo.lock
index 5049f84..9f3d18c 100644
--- a/compiler/Cargo.lock
+++ b/compiler/Cargo.lock
@@ -4,4 +4,4 @@ version = 3
 
 [[package]]
 name = "glagol"
-version = "1.0.0-beta.2"
+version = "1.0.0-beta.3"
diff --git a/compiler/Cargo.toml b/compiler/Cargo.toml
index 1099b18..25317cf 100644
--- a/compiler/Cargo.toml
+++ b/compiler/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "glagol"
-version = "1.0.0-beta.2"
+version = "1.0.0-beta.3"
 edition = "2021"
 description = "Glagol, the first compiler for the Slovo language"
 license = "MIT OR Apache-2.0"
diff --git a/docs/POST_BETA_ROADMAP.md b/docs/POST_BETA_ROADMAP.md
index 3f3e443..16c9c12 100644
--- a/docs/POST_BETA_ROADMAP.md
+++ b/docs/POST_BETA_ROADMAP.md
@@ -87,7 +87,7 @@ Work:
 - identify helpers that should wait for generics instead of being copied across
   concrete type families
 
-Started on `main` after `1.0.0-beta.2`: `docs/language/STDLIB_API.md` is
+Released in `1.0.0-beta.3`: `docs/language/STDLIB_API.md` is
 generated from `lib/std/*.slo` and guarded by `scripts/release-gate.sh`.
 `examples/projects/stdlib-composition` adds a realistic command-line project
 that composes `std.fs`, `std.string`, `std.math`, and `std.io` through explicit
diff --git a/docs/compiler/RELEASE_NOTES.md b/docs/compiler/RELEASE_NOTES.md
index 50bb4ab..04a0b29 100644
--- a/docs/compiler/RELEASE_NOTES.md
+++ b/docs/compiler/RELEASE_NOTES.md
@@ -12,6 +12,37 @@ integration/readiness release, not the first real beta.
 
 No unreleased changes yet.
 
+## 1.0.0-beta.3
+
+Release label: `1.0.0-beta.3`
+
+Release date: 2026-05-22
+
+Release state: standard-library stabilization beta update
+
+### Summary
+
+Glagol `1.0.0-beta.3` keeps the `1.0.0-beta` compiler support baseline and
+adds the first standard-library stabilization bundle:
+
+- `scripts/render-stdlib-api-doc.sh` generates
+  `docs/language/STDLIB_API.md` from repo-root `lib/std/*.slo`
+- the release gate now verifies that generated standard-library API catalog
+  before tests and smoke checks complete
+- `examples/projects/stdlib-composition` proves a realistic multi-module
+  standard-library program through `fmt --check`, `check`, `test`, `doc`, and
+  hosted `glagol run` when the local toolchain is available
+- `compiler/tests/standard_stdlib_composition_beta.rs` gates that composition
+  example and guards against accidental local module copies
+- project-local `.slovo/` build artifacts are ignored so `glagol run` output
+  stays out of commits
+
+### Explicit Deferrals
+
+This release does not add syntax, generics, stable standard-library API
+promises, stable ABI/layout guarantees, richer host error codes, networking, or
+async runtime behavior.
+
 ## 1.0.0-beta.2
 
 Release label: `1.0.0-beta.2`
diff --git a/docs/compiler/ROADMAP.md b/docs/compiler/ROADMAP.md
index 98939d2..bb4ef16 100644
--- a/docs/compiler/ROADMAP.md
+++ b/docs/compiler/ROADMAP.md
@@ -22,11 +22,12 @@ general-purpose beta release.
 
 A Glagol feature is done only when it has parser/lowerer support, checker behavior, diagnostics for invalid forms, backend behavior or explicit unsupported diagnostics, and tests.
 
-Current stage: `1.0.0-beta.2`, released on 2026-05-22 as the first post-beta
-runtime/resource foundation update. It keeps the `1.0.0-beta` language/compiler
-support baseline and includes the `1.0.0-beta.1` tooling hardening release plus
-beta-scoped `std.fs` resource handles, filesystem status checks, file removal,
-and single-directory creation.
+Current stage: `1.0.0-beta.3`, released on 2026-05-22 as the first post-beta
+standard-library stabilization update. It keeps the `1.0.0-beta`
+language/compiler support baseline and includes the `1.0.0-beta.1` tooling
+hardening release, the `1.0.0-beta.2` runtime/resource foundation release, the
+generated standard-library API catalog gate, and focused multi-module stdlib
+composition coverage.
 
 The final experimental precursor scope is `exp-125`. Its unsigned direct-value
 flow, parse/format runtime lanes, and matching staged stdlib helper breadth
diff --git a/docs/language/RELEASE_NOTES.md b/docs/language/RELEASE_NOTES.md
index 4273da1..fb32aea 100644
--- a/docs/language/RELEASE_NOTES.md
+++ b/docs/language/RELEASE_NOTES.md
@@ -8,15 +8,43 @@ Historical `exp-*` releases listed here are experimental maturity milestones.
 The pushed tag `v2.0.0-beta.1` is historical. It is now documented as an
 experimental integration/readiness release, not as a beta maturity claim.
 
-The current release is `1.0.0-beta.2`, published on 2026-05-22. It keeps the
+The current release is `1.0.0-beta.3`, published on 2026-05-22. It keeps the
 `1.0.0-beta` language surface, includes the first post-beta tooling/install
 hardening bundle from `1.0.0-beta.1`, and adds the first runtime/resource
-foundation bundle.
+foundation bundle from `1.0.0-beta.2` plus the first standard-library
+stabilization bundle.
 
 ## Unreleased
 
 No unreleased changes yet.
 
+## 1.0.0-beta.3
+
+Release label: `1.0.0-beta.3`
+
+Release name: Standard Library Stabilization Bundle
+
+Release date: 2026-05-22
+
+Status: released beta standard-library stabilization update on the
+`1.0.0-beta` language baseline.
+
+`1.0.0-beta.3` contains the first standard-library stabilization slice:
+
+- `docs/language/STDLIB_API.md` is generated from the exported helpers in
+  `lib/std/*.slo`
+- `scripts/render-stdlib-api-doc.sh` regenerates that catalog, and
+  `scripts/release-gate.sh` fails if the generated catalog is stale
+- `examples/projects/stdlib-composition` adds a realistic command-line project
+  that composes explicit `std.fs`, `std.string`, `std.math`, and `std.io`
+  imports for file write/read, parse, compute, cleanup, and hosted run output
+- `.llm/BETA_3_STDLIB_STABILIZATION.md` records the beta.3 stabilization
+  contract and deferred decisions
+
+This release does not freeze stable standard-library APIs. It still defers
+generics, an automatic prelude, stable ABI/layout guarantees, richer host error
+codes, maps/sets, networking, and async behavior.
+
 ## 1.0.0-beta.2
 
 Release label: `1.0.0-beta.2`
diff --git a/docs/language/ROADMAP.md b/docs/language/ROADMAP.md
index 8a9b858..7296826 100644
--- a/docs/language/ROADMAP.md
+++ b/docs/language/ROADMAP.md
@@ -10,11 +10,12 @@ Long-horizon planning lives in
 release train from the historical `v2.0.0-beta.1` tag toward and beyond the
 first real general-purpose beta Slovo contract.
 
-Current stage: `1.0.0-beta.2`, released on 2026-05-22 as the first post-beta
-runtime/resource foundation update. It keeps the `1.0.0-beta` language
-contract and includes the `1.0.0-beta.1` tooling hardening release plus
-beta-scoped `std.fs` resource handles, filesystem status checks, file removal,
-and single-directory creation.
+Current stage: `1.0.0-beta.3`, released on 2026-05-22 as the first post-beta
+standard-library stabilization update. It keeps the `1.0.0-beta` language
+contract and includes the `1.0.0-beta.1` tooling hardening release, the
+`1.0.0-beta.2` runtime/resource foundation release, the generated
+standard-library API catalog, and a checked multi-module stdlib composition
+project.
 
 The final experimental precursor scope is `exp-125`, defined in
 `.llm/EXP_125_UNSIGNED_U32_U64_NUMERIC_AND_STDLIB_BREADTH_ALPHA.md`. Its
diff --git a/docs/language/STDLIB_API.md b/docs/language/STDLIB_API.md
index e198d65..9cdb8b8 100644
--- a/docs/language/STDLIB_API.md
+++ b/docs/language/STDLIB_API.md
@@ -6,7 +6,7 @@ Do not edit this file by hand.
 ## Stability Tiers
 
 - `beta-supported`: exported from `lib/std` and covered by source-search, promotion, or facade gates in the current beta line.
-- `experimental`: not used for exported `lib/std` helpers in `1.0.0-beta.2`; future releases may mark new helpers this way before they graduate.
+- `experimental`: not used for exported `lib/std` helpers in `1.0.0-beta.3`; future releases may mark new helpers this way before they graduate.
 - `internal`: helper names that are not exported from their module; they are intentionally omitted from this catalog.
 
 The catalog is a beta compatibility aid, not a stable `1.0.0` API freeze.
diff --git a/docs/language/examples/README.md b/docs/language/examples/README.md
index 4f4728c..ed2b042 100644
--- a/docs/language/examples/README.md
+++ b/docs/language/examples/README.md
@@ -8,11 +8,11 @@ Entries in this section are current compiler support under the matching
 release notes. The current compiler-supported language baseline is
 `1.0.0-beta`; `1.0.0-beta.1` adds tooling/install hardening without changing
 these source-language fixtures. `1.0.0-beta.2` adds beta-scoped
-runtime/resource foundation APIs. Current `main` after `1.0.0-beta.2` also
-adds the generated stdlib API catalog and the checked
-`projects/stdlib-composition/` example. The language baseline absorbs the final
-exp-125 unsigned precursor scope alongside the already promoted project/package,
-stdlib-source, collection, composite-data, formatter, and diagnostics surface.
+runtime/resource foundation APIs. `1.0.0-beta.3` adds the generated stdlib API
+catalog and the checked `projects/stdlib-composition/` example. The language
+baseline absorbs the final exp-125 unsigned precursor scope alongside the
+already promoted project/package, stdlib-source, collection, composite-data,
+formatter, and diagnostics surface.
 
 `supported/add.slo` is the current executable promotion fixture. Glagol can parse it,
 lower it, type-check it, emit LLVM for it, and cover that output with an automated
diff --git a/docs/papers/GLAGOL_COMPILER_MANIFEST.pdf b/docs/papers/GLAGOL_COMPILER_MANIFEST.pdf
index c9f210a..46ebda8 100644
Binary files a/docs/papers/GLAGOL_COMPILER_MANIFEST.pdf and b/docs/papers/GLAGOL_COMPILER_MANIFEST.pdf differ
diff --git a/docs/papers/GLAGOL_WHITEPAPER.md b/docs/papers/GLAGOL_WHITEPAPER.md
index 1d491eb..991727e 100644
--- a/docs/papers/GLAGOL_WHITEPAPER.md
+++ b/docs/papers/GLAGOL_WHITEPAPER.md
@@ -5,16 +5,17 @@
 Sanjin Gumbarevic<br>
 hermeticum_lab@protonmail.com
 
-Publication release: `1.0.0-beta.2`
+Publication release: `1.0.0-beta.3`
 
 Technical behavior baseline: compiler and language support through
 `1.0.0-beta`; tooling and install workflow through `1.0.0-beta.1`;
-runtime/resource foundation through `1.0.0-beta.2`
+runtime/resource foundation through `1.0.0-beta.2`; standard-library
+stabilization through `1.0.0-beta.3`
 
 Date: 2026-05-22
 
 Evidence source: paired local Slovo/Glagol monorepo verification and benchmark
-reruns from a local checkout; beta.2 release-gate verification from the public
+reruns from a local checkout; beta.3 release-gate verification from the public
 monorepo
 
 Maturity: beta
@@ -26,16 +27,17 @@ Slovo. It exists to make the language support boundary inspectable: tokens,
 S-expression tree, AST, typed AST, LLVM IR, hosted native executable, tests,
 diagnostics, and release documents should agree.
 
-The current publication release, `1.0.0-beta.2`, keeps the first real
+The current publication release, `1.0.0-beta.3`, keeps the first real
 general-purpose beta toolchain baseline from `1.0.0-beta` and records the
 first post-beta tooling/install hardening update plus the first
-runtime/resource foundation update. The beta baseline includes
+runtime/resource foundation update plus the first standard-library
+stabilization update. The beta baseline includes
 the completed `u32` / `u64` unsigned compiler and stdlib breadth scope
 alongside the current nine-kernel benchmark suite. This paper records the
 current beta implementation surface, the benchmark method and results, the
 distinction between Glagol and Lisp-family implementations, the beta.1 tooling
-update, the beta.2 runtime/resource foundation, and the compiler path from beta
-to stable.
+update, the beta.2 runtime/resource foundation, the beta.3 standard-library
+stabilization slice, and the compiler path from beta to stable.
 
 ## 1. Compiler Thesis
 
@@ -119,7 +121,7 @@ At the current technical behavior beta baseline, Glagol supports:
 - benchmark scaffolds for Slovo, C, Rust, Python, Clojure, and Common
   Lisp/SBCL, with `cold-process` and `hot-loop` timing modes
 
-The current release, `1.0.0-beta.2`, is a beta runtime/resource foundation
+The current release, `1.0.0-beta.3`, is a beta standard-library stabilization
 update on the first release line that may honestly use beta maturity language
 for this toolchain.
 
@@ -278,7 +280,8 @@ python3 benchmarks/vec-string-eq-loop/run.py --mode cold-process --repeats 3 --w
 
 The benchmark rows below remain the full-suite `1.0.0-beta` publication
 baseline. `1.0.0-beta.1` changes tooling and install workflow, and
-`1.0.0-beta.2` adds runtime/resource APIs; neither release claims changed
+`1.0.0-beta.2` adds runtime/resource APIs. `1.0.0-beta.3` adds standard-library
+catalog and composition coverage. None of these post-beta slices claims changed
 benchmark performance.
 
 The exp-123 publication baseline widened the paired same-machine result set
@@ -367,12 +370,12 @@ coverage and compatibility:
 - package behavior becoming stable before dependency, manifest, and versioning
   rules are precise
 
-## 9. Path Beyond `1.0.0-beta.2`
+## 9. Path Beyond `1.0.0-beta.3`
 
 Glagol now implements the first real beta Slovo contract, the first
-post-beta tooling/install hardening release, and the first runtime/resource
-foundation release. The remaining path is from beta
-to stable.
+post-beta tooling/install hardening release, the first runtime/resource
+foundation release, and the first standard-library stabilization release. The
+remaining path is from beta to stable.
 
 Recommended compiler sequence:
 
diff --git a/docs/papers/GLAGOL_WHITEPAPER.pdf b/docs/papers/GLAGOL_WHITEPAPER.pdf
index 89a1b46..685b4e4 100644
Binary files a/docs/papers/GLAGOL_WHITEPAPER.pdf and b/docs/papers/GLAGOL_WHITEPAPER.pdf differ
diff --git a/docs/papers/SLOVO_MANIFEST.pdf b/docs/papers/SLOVO_MANIFEST.pdf
index 01739f5..cc2a9ce 100644
Binary files a/docs/papers/SLOVO_MANIFEST.pdf and b/docs/papers/SLOVO_MANIFEST.pdf differ
diff --git a/docs/papers/SLOVO_WHITEPAPER.md b/docs/papers/SLOVO_WHITEPAPER.md
index 2eea273..9181443 100644
--- a/docs/papers/SLOVO_WHITEPAPER.md
+++ b/docs/papers/SLOVO_WHITEPAPER.md
@@ -5,16 +5,16 @@
 Sanjin Gumbarevic<br>
 hermeticum_lab@protonmail.com
 
-Publication release: `1.0.0-beta.2`
+Publication release: `1.0.0-beta.3`
 
 Technical behavior baseline: language surface through `1.0.0-beta`; tooling
 and install workflow through `1.0.0-beta.1`; runtime/resource foundation through
-`1.0.0-beta.2`
+`1.0.0-beta.2`; standard-library stabilization through `1.0.0-beta.3`
 
 Date: 2026-05-22
 
 Evidence source: paired local Slovo/Glagol monorepo verification and benchmark
-reruns from a local checkout; beta.2 release-gate verification from the public
+reruns from a local checkout; beta.3 release-gate verification from the public
 monorepo
 
 Maturity: beta
@@ -29,23 +29,25 @@ explicit types, explicit failure through `option` and `result`, lexical
 `unsafe`, and native compilation through the Glagol compiler to LLVM IR and
 hosted executables.
 
-The current publication release, `1.0.0-beta.2`, keeps the first real
+The current publication release, `1.0.0-beta.3`, keeps the first real
 general-purpose beta language baseline from `1.0.0-beta` and records the first
 post-beta tooling/install hardening update plus the first runtime/resource
-foundation update. The beta baseline includes the
+foundation update plus the first standard-library stabilization update. The
+beta baseline includes the
 completed `u32` / `u64` unsigned scope, the staged stdlib breadth that makes
 ordinary command-line programs practical, and the current nine-kernel
 benchmark suite. This paper records the current beta technical state, the
 difference between Slovo and Lisp-family languages, the benchmark methodology,
-the beta.1 tooling update, the beta.2 runtime/resource foundation, and the
-remaining path from beta to stable.
+the beta.1 tooling update, the beta.2 runtime/resource foundation, the beta.3
+standard-library stabilization slice, and the remaining path from beta to
+stable.
 
 ## 1. Scope
 
 This document is a technical state paper for the current beta baseline. It
 summarizes the behavior represented by the paired local Slovo and Glagol
 workspaces, with `1.0.0-beta` as the current language-surface baseline and
-`1.0.0-beta.1` as the current publication/tooling baseline.
+`1.0.0-beta.3` as the current publication baseline.
 
 The support rule remains strict:
 
@@ -57,7 +59,7 @@ The support rule remains strict:
 - partial parser recognition or speculative examples do not count as support
 
 Historical `exp-*` releases remain experimental alpha maturity. The current
-publication accompanies `1.0.0-beta.1`.
+publication accompanies `1.0.0-beta.3`.
 
 ## 2. Design Thesis
 
@@ -355,7 +357,8 @@ python3 benchmarks/vec-string-eq-loop/run.py --mode cold-process --repeats 3 --w
 
 The benchmark rows below remain the full-suite `1.0.0-beta` publication
 baseline. `1.0.0-beta.1` changes tooling and install workflow, and
-`1.0.0-beta.2` adds runtime/resource APIs; neither release claims changed
+`1.0.0-beta.2` adds runtime/resource APIs. `1.0.0-beta.3` adds standard-library
+catalog and composition coverage. None of these post-beta slices claims changed
 benchmark performance.
 
 The exp-123 publication baseline widened the paired same-machine result set
@@ -477,13 +480,14 @@ Major remaining gaps before `1.0.0`:
 - semantic versioning and deprecation policy
 - a clear separation between stable and experimental features
 
-## 10. Path Beyond `1.0.0-beta.2`
+## 10. Path Beyond `1.0.0-beta.3`
 
 The beta threshold is now real. The next work should treat `1.0.0-beta` as
 the language compatibility-governed baseline, `1.0.0-beta.1` as the first
-tooling/install hardening point, and `1.0.0-beta.2` as the first
-runtime/resource foundation point, then move deliberately toward stable
-general-purpose status.
+tooling/install hardening point, `1.0.0-beta.2` as the first runtime/resource
+foundation point, and `1.0.0-beta.3` as the first standard-library
+stabilization point, then move deliberately toward stable general-purpose
+status.
 
 Recommended sequence:
 
diff --git a/docs/papers/SLOVO_WHITEPAPER.pdf b/docs/papers/SLOVO_WHITEPAPER.pdf
index e253f04..89b216f 100644
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