diff --git a/.gitea/workflows/prepare-release.yml b/.gitea/workflows/prepare-release.yml
new file mode 100644
index 0000000..6fc9a5d
--- /dev/null
+++ b/.gitea/workflows/prepare-release.yml
@@ -0,0 +1,83 @@
+name: Prepare Release
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: Semantic version to release, with or without leading v.
+        required: true
+
+jobs:
+  prepare:
+    runs-on: ubuntu-latest
+    container: docker.io/catthehacker/ubuntu:act-latest
+    defaults:
+      run:
+        shell: bash
+    env:
+      RELEASE_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.26.1'
+          check-latest: true
+          cache: true
+          cache-dependency-path: go.sum
+
+      - name: Prepare release files
+        env:
+          RELEASE_VERSION: ${{ inputs.version }}
+        run: |
+          set -euo pipefail
+          ./script/prepare-release.sh "$RELEASE_VERSION"
+
+      - name: Run tests
+        run: |
+          set -euo pipefail
+          go test ./...
+
+      - name: Configure git author
+        run: |
+          set -euo pipefail
+          git config user.name "gitea-actions[bot]"
+          git config user.email "gitea-actions[bot]@users.noreply.local"
+
+      - name: Commit release changes and push tag
+        env:
+          RELEASE_VERSION: ${{ inputs.version }}
+        run: |
+          set -euo pipefail
+
+          normalized_version="${RELEASE_VERSION#v}"
+          tag="v${normalized_version}"
+
+          if git rev-parse "$tag" >/dev/null 2>&1; then
+            echo "Tag ${tag} already exists" >&2
+            exit 1
+          fi
+
+          case "$GITHUB_SERVER_URL" in
+            https://*)
+              authed_remote="https://oauth2:${RELEASE_TOKEN}@${GITHUB_SERVER_URL#https://}/${GITHUB_REPOSITORY}.git"
+              ;;
+            http://*)
+              authed_remote="http://oauth2:${RELEASE_TOKEN}@${GITHUB_SERVER_URL#http://}/${GITHUB_REPOSITORY}.git"
+              ;;
+            *)
+              echo "Unsupported GITHUB_SERVER_URL: ${GITHUB_SERVER_URL}" >&2
+              exit 1
+              ;;
+          esac
+
+          git remote set-url origin "$authed_remote"
+          git add changelog.md internal/releaseprep/version/version.go
+          git commit -m "release: prepare ${tag}"
+          git tag "$tag"
+          git push origin HEAD
+          git push origin "$tag"
diff --git a/.gitea/workflows/push-validation.yml b/.gitea/workflows/push-validation.yml
new file mode 100644
index 0000000..cc4c723
--- /dev/null
+++ b/.gitea/workflows/push-validation.yml
@@ -0,0 +1,56 @@
+name: Push Validation
+
+on:
+  push:
+    branches:
+      - "**"
+    tags-ignore:
+      - "*"
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    container: docker.io/catthehacker/ubuntu:act-latest
+    defaults:
+      run:
+        shell: bash
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.26.1'
+          check-latest: true
+          cache: true
+          cache-dependency-path: go.sum
+
+      - name: Run full unit test suite with coverage
+        run: |
+          set -euo pipefail
+          go test -covermode=atomic -coverprofile=coverage.out ./...
+          go tool cover -func=coverage.out
+
+      - name: Recommend next release tag on main pushes
+        if: ${{ github.ref == 'refs/heads/main' }}
+        run: |
+          set -euo pipefail
+
+          if recommended_tag="$(go run ./cmd/releaseprep --recommend --root . 2>release-recommendation.err)"; then
+            {
+              echo
+              echo '## Release Recommendation'
+              echo
+              echo "- Recommended next tag: \`${recommended_tag}\`"
+            } >> "$GITHUB_STEP_SUMMARY"
+          else
+            recommendation_error="$(tr '\n' ' ' < release-recommendation.err | sed 's/[[:space:]]\+/ /g' | sed 's/^ //; s/ $//')"
+            echo "::warning::${recommendation_error}"
+            {
+              echo
+              echo '## Release Recommendation'
+              echo
+              echo "- No recommended tag emitted: ${recommendation_error}"
+            } >> "$GITHUB_STEP_SUMMARY"
+          fi
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e5f1b2e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,53 @@
+# vociferate
+
+A reusable release preparation tool for Go repositories.
+
+## Build
+
+Build with just:
+
+```bash
+just go-build
+```
+
+Or directly with Go:
+
+```bash
+go build -o dist/releaseprep ./cmd/releaseprep
+```
+
+## Usage
+
+Prepare release files:
+
+```bash
+go run ./cmd/releaseprep --version v1.2.3 --date 2026-03-20 --root .
+```
+
+Recommend next release tag from changelog content:
+
+```bash
+go run ./cmd/releaseprep --recommend --root .
+```
+
+### Flags
+
+- `--version` semantic version to release (with or without leading `v`).
+- `--date` release date in `YYYY-MM-DD` format.
+- `--recommend` print recommended next tag based on `## [Unreleased]`.
+- `--root` repository root directory.
+- `--version-file` path to version source file relative to `--root`.
+- `--version-pattern` regexp with exactly one capture group for version value.
+- `--changelog` path to changelog file relative to `--root`.
+
+Defaults:
+
+- `version-file`: `internal/releaseprep/version/version.go`
+- `version-pattern`: `const String = "([^"]+)"`
+- `changelog`: `changelog.md`
+
+## Testing
+
+```bash
+just go-test
+```
diff --git a/action.yml b/action.yml
new file mode 100644
index 0000000..f0e681b
--- /dev/null
+++ b/action.yml
@@ -0,0 +1,63 @@
+name: releaseprep
+description: Prepare release files or recommend a next semantic version tag.
+
+inputs:
+  version:
+    description: Semantic version to release.
+    required: false
+  version-file:
+    description: Path to version file relative to repository root.
+    required: false
+    default: ''
+  version-pattern:
+    description: Regular expression with one capture group for current version.
+    required: false
+    default: ''
+  changelog:
+    description: Path to changelog file relative to repository root.
+    required: false
+    default: changelog.md
+  recommend:
+    description: If true, print recommended next release tag.
+    required: false
+    default: 'false'
+
+runs:
+  using: composite
+  steps:
+    - uses: actions/checkout@v4
+
+    - uses: actions/setup-go@v5
+      with:
+        go-version: '1.26.1'
+
+    - name: Run releaseprep
+      shell: bash
+      run: |
+        set -euo pipefail
+
+        args=(--root .)
+
+        if [[ "${{ inputs.recommend }}" == "true" ]]; then
+          args+=(--recommend)
+        else
+          if [[ -z "${{ inputs.version }}" ]]; then
+            echo "input 'version' is required when recommend is false" >&2
+            exit 2
+          fi
+          args+=(--version "${{ inputs.version }}" --date "$(date -u +%F)")
+        fi
+
+        if [[ -n "${{ inputs.version-file }}" ]]; then
+          args+=(--version-file "${{ inputs.version-file }}")
+        fi
+
+        if [[ -n "${{ inputs.version-pattern }}" ]]; then
+          args+=(--version-pattern "${{ inputs.version-pattern }}")
+        fi
+
+        if [[ -n "${{ inputs.changelog }}" ]]; then
+          args+=(--changelog "${{ inputs.changelog }}")
+        fi
+
+        go run git.hrafn.xyz/aether/vociferate/cmd/releaseprep@latest "${args[@]}"
diff --git a/cmd/releaseprep/main.go b/cmd/releaseprep/main.go
new file mode 100644
index 0000000..1884d7e
--- /dev/null
+++ b/cmd/releaseprep/main.go
@@ -0,0 +1,53 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"git.hrafn.xyz/aether/vociferate/internal/releaseprep"
+)
+
+func main() {
+	version := flag.String("version", "", "semantic version to release, with or without leading v")
+	date := flag.String("date", "", "release date in YYYY-MM-DD format")
+	recommend := flag.Bool("recommend", false, "print the recommended next release tag based on the changelog")
+	root := flag.String("root", ".", "repository root to update")
+	versionFile := flag.String("version-file", "", "path to the version file, relative to --root")
+	versionPattern := flag.String("version-pattern", "", "regexp with one capture group for the version value")
+	changelog := flag.String("changelog", "", "path to changelog file, relative to --root")
+	flag.Parse()
+
+	absRoot, err := filepath.Abs(*root)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "resolve root: %v\n", err)
+		os.Exit(1)
+	}
+
+	opts := releaseprep.Options{
+		VersionFile:    *versionFile,
+		VersionPattern: *versionPattern,
+		Changelog:      *changelog,
+	}
+
+	if *recommend {
+		tag, err := releaseprep.RecommendedTag(absRoot, opts)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "recommend release: %v\n", err)
+			os.Exit(1)
+		}
+		fmt.Println(tag)
+		return
+	}
+
+	if *version == "" || *date == "" {
+		fmt.Fprintln(os.Stderr, "usage: releaseprep --version <version> --date <YYYY-MM-DD> [--root <dir>] [--version-file <path>] [--version-pattern <regexp>] [--changelog <path>] | --recommend [--root <dir>] [--version-file <path>] [--version-pattern <regexp>] [--changelog <path>]")
+		os.Exit(2)
+	}
+
+	if err := releaseprep.Prepare(absRoot, *version, *date, opts); err != nil {
+		fmt.Fprintf(os.Stderr, "prepare release: %v\n", err)
+		os.Exit(1)
+	}
+}
diff --git a/internal/releaseprep/releaseprep.go b/internal/releaseprep/releaseprep.go
new file mode 100644
index 0000000..f167812
--- /dev/null
+++ b/internal/releaseprep/releaseprep.go
@@ -0,0 +1,271 @@
+package releaseprep
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+const (
+	defaultVersionFile = "internal/releaseprep/version/version.go"
+	defaultVersionExpr = `const String = "([^"]+)"`
+	defaultChangelog   = "changelog.md"
+)
+
+type Options struct {
+	VersionFile    string
+	VersionPattern string
+	Changelog      string
+}
+
+type semver struct {
+	major int
+	minor int
+	patch int
+}
+
+type resolvedOptions struct {
+	VersionFile string
+	VersionExpr *regexp.Regexp
+	Changelog   string
+}
+
+func Prepare(rootDir, version, releaseDate string, options Options) error {
+	normalizedVersion := strings.TrimPrefix(strings.TrimSpace(version), "v")
+	if normalizedVersion == "" {
+		return fmt.Errorf("version must not be empty")
+	}
+
+	releaseDate = strings.TrimSpace(releaseDate)
+	if releaseDate == "" {
+		return fmt.Errorf("release date must not be empty")
+	}
+
+	resolved, err := resolveOptions(options)
+	if err != nil {
+		return err
+	}
+
+	if err := updateVersionFile(rootDir, normalizedVersion, resolved); err != nil {
+		return err
+	}
+
+	if err := updateChangelog(rootDir, normalizedVersion, releaseDate, resolved.Changelog); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func RecommendedTag(rootDir string, options Options) (string, error) {
+	resolved, err := resolveOptions(options)
+	if err != nil {
+		return "", err
+	}
+
+	currentVersion, err := readCurrentVersion(rootDir, resolved)
+	if err != nil {
+		return "", err
+	}
+
+	unreleasedBody, err := readUnreleasedBody(rootDir, resolved.Changelog)
+	if err != nil {
+		return "", err
+	}
+
+	parsed, err := parseSemver(currentVersion)
+	if err != nil {
+		return "", err
+	}
+
+	switch {
+	case sectionHasEntries(unreleasedBody, "Breaking"), sectionHasEntries(unreleasedBody, "Removed"):
+		parsed.major++
+		parsed.minor = 0
+		parsed.patch = 0
+	case sectionHasEntries(unreleasedBody, "Added"):
+		parsed.minor++
+		parsed.patch = 0
+	default:
+		parsed.patch++
+	}
+
+	return fmt.Sprintf("v%d.%d.%d", parsed.major, parsed.minor, parsed.patch), nil
+}
+
+func sectionHasEntries(unreleasedBody, sectionName string) bool {
+	heading := "### " + sectionName
+	sectionStart := strings.Index(unreleasedBody, heading)
+	if sectionStart == -1 {
+		return false
+	}
+
+	afterHeading := unreleasedBody[sectionStart+len(heading):]
+	if strings.HasPrefix(afterHeading, "\r") {
+		afterHeading = afterHeading[1:]
+	}
+	if strings.HasPrefix(afterHeading, "\n") {
+		afterHeading = afterHeading[1:]
+	}
+
+	nextHeading := strings.Index(afterHeading, "\n### ")
+	sectionBody := afterHeading
+	if nextHeading != -1 {
+		sectionBody = afterHeading[:nextHeading]
+	}
+
+	return strings.TrimSpace(sectionBody) != ""
+}
+
+func resolveOptions(options Options) (resolvedOptions, error) {
+	versionFile := strings.TrimSpace(options.VersionFile)
+	if versionFile == "" {
+		versionFile = defaultVersionFile
+	}
+
+	pattern := strings.TrimSpace(options.VersionPattern)
+	if pattern == "" {
+		pattern = defaultVersionExpr
+	}
+	versionExpr, err := regexp.Compile(pattern)
+	if err != nil {
+		return resolvedOptions{}, fmt.Errorf("compile version pattern: %w", err)
+	}
+	if versionExpr.NumSubexp() != 1 {
+		return resolvedOptions{}, fmt.Errorf("version pattern must contain exactly one capture group")
+	}
+
+	changelog := strings.TrimSpace(options.Changelog)
+	if changelog == "" {
+		changelog = defaultChangelog
+	}
+
+	return resolvedOptions{VersionFile: versionFile, VersionExpr: versionExpr, Changelog: changelog}, nil
+}
+
+func updateVersionFile(rootDir, version string, options resolvedOptions) error {
+	path := filepath.Join(rootDir, options.VersionFile)
+	contents, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("read version file: %w", err)
+	}
+
+	match := options.VersionExpr.FindStringSubmatch(string(contents))
+	if len(match) < 2 {
+		return fmt.Errorf("version value not found in %s", path)
+	}
+
+	replacement := strings.Replace(match[0], match[1], version, 1)
+	updated := strings.Replace(string(contents), match[0], replacement, 1)
+	if updated == string(contents) {
+		return fmt.Errorf("version value not found in %s", path)
+	}
+
+	if err := os.WriteFile(path, []byte(updated), 0o644); err != nil {
+		return fmt.Errorf("write version file: %w", err)
+	}
+
+	return nil
+}
+
+func updateChangelog(rootDir, version, releaseDate, changelogPath string) error {
+	unreleasedBody, text, afterHeader, nextSectionStart, path, err := readChangelogState(rootDir, changelogPath)
+	if err != nil {
+		return err
+	}
+
+	if strings.TrimSpace(unreleasedBody) == "" {
+		return fmt.Errorf("unreleased section is empty")
+	}
+
+	newSection := fmt.Sprintf("## [%s] - %s\n", version, releaseDate)
+	newSection += "\n" + unreleasedBody
+	if !strings.HasSuffix(newSection, "\n") {
+		newSection += "\n"
+	}
+
+	updated := text[:afterHeader] + "\n" + newSection + text[nextSectionStart:]
+	if err := os.WriteFile(path, []byte(updated), 0o644); err != nil {
+		return fmt.Errorf("write changelog: %w", err)
+	}
+
+	return nil
+}
+
+func readCurrentVersion(rootDir string, options resolvedOptions) (string, error) {
+	path := filepath.Join(rootDir, options.VersionFile)
+	contents, err := os.ReadFile(path)
+	if err != nil {
+		return "", fmt.Errorf("read version file: %w", err)
+	}
+
+	match := options.VersionExpr.FindStringSubmatch(string(contents))
+	if len(match) < 2 {
+		return "", fmt.Errorf("version value not found in %s", path)
+	}
+
+	return strings.TrimSpace(match[1]), nil
+}
+
+func readUnreleasedBody(rootDir, changelogPath string) (string, error) {
+	unreleasedBody, _, _, _, _, err := readChangelogState(rootDir, changelogPath)
+	if err != nil {
+		return "", err
+	}
+
+	if strings.TrimSpace(unreleasedBody) == "" {
+		return "", fmt.Errorf("unreleased section is empty")
+	}
+
+	return unreleasedBody, nil
+}
+
+func readChangelogState(rootDir, changelogPath string) (string, string, int, int, string, error) {
+	path := filepath.Join(rootDir, changelogPath)
+	contents, err := os.ReadFile(path)
+	if err != nil {
+		return "", "", 0, 0, "", fmt.Errorf("read changelog: %w", err)
+	}
+
+	text := string(contents)
+	unreleasedHeader := "## [Unreleased]\n"
+	start := strings.Index(text, unreleasedHeader)
+	if start == -1 {
+		return "", "", 0, 0, "", fmt.Errorf("unreleased section not found in changelog")
+	}
+
+	afterHeader := start + len(unreleasedHeader)
+	nextSectionRelative := strings.Index(text[afterHeader:], "\n## [")
+	if nextSectionRelative == -1 {
+		nextSectionRelative = len(text[afterHeader:])
+	}
+	nextSectionStart := afterHeader + nextSectionRelative
+	unreleasedBody := strings.TrimLeft(text[afterHeader:nextSectionStart], "\n")
+
+	return unreleasedBody, text, afterHeader, nextSectionStart, path, nil
+}
+
+func parseSemver(version string) (semver, error) {
+	parts := strings.Split(strings.TrimSpace(version), ".")
+	if len(parts) != 3 {
+		return semver{}, fmt.Errorf("version %q is not semantic major.minor.patch", version)
+	}
+
+	major, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return semver{}, fmt.Errorf("parse major version: %w", err)
+	}
+	minor, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return semver{}, fmt.Errorf("parse minor version: %w", err)
+	}
+	patch, err := strconv.Atoi(parts[2])
+	if err != nil {
+		return semver{}, fmt.Errorf("parse patch version: %w", err)
+	}
+
+	return semver{major: major, minor: minor, patch: patch}, nil
+}
diff --git a/internal/releaseprep/version/version.go b/internal/releaseprep/version/version.go
new file mode 100644
index 0000000..59fc368
--- /dev/null
+++ b/internal/releaseprep/version/version.go
@@ -0,0 +1,3 @@
+package version
+
+const String = "0.1.0"
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..18f41d4
--- /dev/null
+++ b/justfile
@@ -0,0 +1,14 @@
+set shell := ["bash", "-eu", "-o", "pipefail", "-c"]
+
+default:
+  @just --list
+
+go-build:
+  @mkdir -p dist
+  go build -o dist/releaseprep ./cmd/releaseprep
+
+go-test:
+  go test ./...
+
+prepare-release version:
+  ./script/prepare-release.sh "{{version}}"
diff --git a/script/prepare-release.sh b/script/prepare-release.sh
new file mode 100755
index 0000000..3c5863a
--- /dev/null
+++ b/script/prepare-release.sh
@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ $# -ne 1 ]]; then
+  echo "usage: $0 <version>" >&2
+  exit 2
+fi
+
+repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+release_date="$(date -u +%F)"
+
+go run ./cmd/releaseprep \
+  --root "$repo_root" \
+  --version "$1" \
+  --date "$release_date" \
+  --version-file internal/releaseprep/version/version.go \
+  --version-pattern 'const String = "([^"]+)"' \
+  --changelog changelog.md