diff --git a/.github/scripts/resolve-dependency-refs.sh b/.github/scripts/resolve-dependency-refs.sh
new file mode 100644
index 000000000..f0adaebfe
--- /dev/null
+++ b/.github/scripts/resolve-dependency-refs.sh
@@ -0,0 +1,382 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+if (( $# < 3 || $# % 2 == 0 )); then
+  echo "Usage: $0 SOURCE_DIRECTORY OUTPUT_PREFIX DEPENDENCY_REPOSITORY [...]" >&2
+  exit 2
+fi
+
+source_directory=$1
+shift
+
+source_branch=${SOURCE_BRANCH:?SOURCE_BRANCH must name the branch being tested}
+integration_branch=${INTEGRATION_BRANCH:-staging}
+root_branch=${ROOT_BRANCH:-master}
+
+declare -a dependency_prefixes=()
+declare -a dependency_repositories=()
+while (( $# )); do
+  dependency_prefixes+=("$1")
+  dependency_repositories+=("$2")
+  shift 2
+done
+
+repository_url() {
+  local repository=$1
+  if [[ $repository == *://* || $repository == /* ]]; then
+    echo "$repository"
+  else
+    echo "https://github.com/${repository}.git"
+  fi
+}
+
+evidence_directory=$(mktemp -d)
+declare -a evidence_paths=("$source_directory")
+declare -a evidence_ref_prefixes=("refs/remotes/origin/")
+declare -A cloned_paths=()
+
+clone_evidence_repository() {
+  local repository=$1
+
+  if [[ -n ${cloned_paths[$repository]+yes} ]]; then
+    return
+  fi
+
+  local clone_path="${evidence_directory}/repository-${#cloned_paths[@]}.git"
+  git clone --quiet --bare --filter=blob:none \
+    "$(repository_url "$repository")" "$clone_path"
+  cloned_paths[$repository]=$clone_path
+  evidence_paths+=("$clone_path")
+  evidence_ref_prefixes+=("refs/heads/")
+}
+
+for repository in "${dependency_repositories[@]}"; do
+  clone_evidence_repository "$repository"
+done
+
+if [[ -n ${EVIDENCE_REPOSITORIES:-} ]]; then
+  read -r -a additional_evidence <<< "$EVIDENCE_REPOSITORIES"
+  for repository in "${additional_evidence[@]}"; do
+    clone_evidence_repository "$repository"
+  done
+fi
+
+# A moved branch is relevant only when its name is shared by repositories.
+# Count each repository once so private one-off branches do not pollute the
+# global candidate set.
+declare -A branch_presence=()
+for ((repository_index = 0; repository_index < ${#evidence_paths[@]}; repository_index++)); do
+  repository_path=${evidence_paths[$repository_index]}
+  ref_prefix=${evidence_ref_prefixes[$repository_index]}
+  while IFS= read -r ref; do
+    branch=${ref#"$ref_prefix"}
+    [[ $branch == HEAD ]] && continue
+    branch_presence[$branch]=$(( ${branch_presence[$branch]:-0} + 1 ))
+  done < <(
+    git -C "$repository_path" for-each-ref \
+      --format='%(refname)' "${ref_prefix%/}"
+  )
+done
+
+declare -a candidates=()
+declare -A seen_candidates=()
+declare -A candidate_proven=()
+
+add_candidate() {
+  local branch=$1
+  local proven=${2:-true}
+  if [[ -n $branch && -z ${seen_candidates[$branch]+yes} ]]; then
+    seen_candidates[$branch]=${#candidates[@]}
+    candidate_proven[${#candidates[@]}]=$proven
+    candidates+=("$branch")
+  elif [[ -n $branch && $proven == true ]]; then
+    candidate_proven[${seen_candidates[$branch]}]=true
+  fi
+}
+
+add_candidate "$source_branch"
+
+collect_candidates() {
+  local repository_path=$1
+  local ref_prefix=$2
+  local start_ref=$3
+  local required=$4
+  local root_ref="${ref_prefix}${root_branch}"
+
+  if ! git -C "$repository_path" rev-parse --verify "${start_ref}^{commit}" >/dev/null 2>&1; then
+    if [[ $required == true ]]; then
+      echo "Cannot resolve the workflow commit in ${repository_path}" >&2
+      exit 1
+    fi
+    return
+  fi
+  if ! git -C "$repository_path" rev-parse --verify "${root_ref}^{commit}" >/dev/null 2>&1; then
+    echo "Cannot find root branch '${root_branch}' in ${repository_path}" >&2
+    exit 1
+  fi
+
+  declare -A distance_by_commit=()
+  local distance=0
+  local reached_root=false
+  local commit
+  while IFS= read -r commit; do
+    distance_by_commit[$commit]=$distance
+    ((distance += 1))
+    if git -C "$repository_path" merge-base --is-ancestor "$commit" "$root_ref"; then
+      reached_root=true
+      break
+    fi
+  done < <(git -C "$repository_path" rev-list --first-parent "$start_ref")
+
+  if [[ $reached_root != true ]]; then
+    if [[ $required == true ]]; then
+      echo "The workflow commit's first-parent history does not reach '${root_branch}'" >&2
+      exit 1
+    fi
+    return
+  fi
+  local root_distance=$((distance - 1))
+
+  local ordered_refs="${evidence_directory}/candidate-refs-${#candidates[@]}-${distance}"
+  : > "$ordered_refs"
+  local ref object branch
+  while IFS=$'\t' read -r ref object; do
+    branch=${ref#"$ref_prefix"}
+    [[ $branch == HEAD ]] && continue
+    [[ $branch == "$source_branch" ]] && continue
+    [[ $branch == "$integration_branch" ]] && continue
+    [[ $branch == "$root_branch" ]] && continue
+
+    if [[ -n ${distance_by_commit[$object]+yes} ]]; then
+      printf '%s\t%s\ttrue\n' "${distance_by_commit[$object]}" "$branch" >> "$ordered_refs"
+      continue
+    fi
+
+    # The branch may have advanced after a child was created. Its merge-base
+    # still identifies the old tip on the event's stack. Requiring the name in
+    # multiple repositories and a fork point newer than the root boundary
+    # avoids treating every branch from master as part of this stack.
+    [[ ${branch_presence[$branch]:-0} -ge 2 ]] || continue
+    merge_base=$(git -C "$repository_path" merge-base "$start_ref" "$ref" 2>/dev/null || true)
+    [[ -n $merge_base && -n ${distance_by_commit[$merge_base]+yes} ]] || continue
+    [[ ${distance_by_commit[$merge_base]} -lt $root_distance ]] || continue
+    printf '%s\t%s\tfalse\n' "${distance_by_commit[$merge_base]}" "$branch" >> "$ordered_refs"
+  done < <(
+    git -C "$repository_path" for-each-ref \
+      --format='%(refname)%09%(objectname)' "${ref_prefix%/}"
+  )
+
+  while IFS=$'\t' read -r _ branch proven; do
+    add_candidate "$branch" "$proven"
+  done < <(sort -k1,1n -k2,2 -u "$ordered_refs")
+}
+
+# HEAD is the immutable event commit. Never substitute the mutable remote tip.
+collect_candidates "$source_directory" "refs/remotes/origin/" HEAD true
+
+for ((repository_index = 1; repository_index < ${#evidence_paths[@]}; repository_index++)); do
+  repository_path=${evidence_paths[$repository_index]}
+  source_ref="refs/heads/${source_branch}"
+  if git -C "$repository_path" show-ref --verify --quiet "$source_ref"; then
+    collect_candidates "$repository_path" "refs/heads/" "$source_ref" false
+  fi
+done
+
+if [[ $source_branch != "$root_branch" ]]; then
+  add_candidate "$integration_branch"
+fi
+add_candidate "$root_branch"
+
+printf -v candidate_chain '%s -> ' "${candidates[@]}"
+candidate_chain=${candidate_chain% -> }
+echo "Dependency branch candidates: ${candidate_chain}"
+
+candidate_count=${#candidates[@]}
+declare -A edges=()
+declare -A strict_edges=()
+
+add_edge() {
+  local newer=$1
+  local older=$2
+  [[ $newer == "$older" ]] || edges["${newer},${older}"]=1
+}
+
+is_first_parent_ancestor() {
+  local repository_path=$1
+  local older=$2
+  local newer=$3
+  local commit
+
+  while IFS= read -r commit; do
+    [[ $commit == "$older" ]] && return 0
+  done < <(git -C "$repository_path" rev-list --first-parent "$newer")
+  return 1
+}
+
+# The event branch is newest by definition. staging and master are the two
+# conventional terminal levels, even when their tips have advanced.
+for ((i = 0; i < candidate_count; i++)); do
+  branch=${candidates[$i]}
+  if [[ $branch != "$source_branch" ]]; then
+    add_edge 0 "$i"
+  fi
+  if [[ $source_branch != "$root_branch" &&
+    $branch != "$integration_branch" && $branch != "$root_branch" ]]; then
+    integration_index=${seen_candidates[$integration_branch]}
+    add_edge "$i" "$integration_index"
+  fi
+done
+root_index=${seen_candidates[$root_branch]}
+if [[ $source_branch != "$root_branch" ]]; then
+  integration_index=${seen_candidates[$integration_branch]}
+  add_edge "$integration_index" "$root_index"
+fi
+
+# Each repository contributes only strict first-parent evidence. Equal refs
+# are neutral; missing or diverged refs contribute no ordering.
+for ((repository_index = 0; repository_index < ${#evidence_paths[@]}; repository_index++)); do
+  repository_path=${evidence_paths[$repository_index]}
+  ref_prefix=${evidence_ref_prefixes[$repository_index]}
+
+  for ((i = 0; i < candidate_count; i++)); do
+    left_branch=${candidates[$i]}
+    [[ $left_branch == "$source_branch" || $left_branch == "$integration_branch" || $left_branch == "$root_branch" ]] && continue
+    left_ref="${ref_prefix}${left_branch}"
+    left_sha=$(git -C "$repository_path" rev-parse --verify "${left_ref}^{commit}" 2>/dev/null || true)
+    [[ -n $left_sha ]] || continue
+
+    for ((j = i + 1; j < candidate_count; j++)); do
+      right_branch=${candidates[$j]}
+      [[ $right_branch == "$source_branch" || $right_branch == "$integration_branch" || $right_branch == "$root_branch" ]] && continue
+      right_ref="${ref_prefix}${right_branch}"
+      right_sha=$(git -C "$repository_path" rev-parse --verify "${right_ref}^{commit}" 2>/dev/null || true)
+      [[ -n $right_sha && $left_sha != "$right_sha" ]] || continue
+
+      if is_first_parent_ancestor "$repository_path" "$right_sha" "$left_sha"; then
+        add_edge "$i" "$j"
+        strict_edges["${i},${j}"]=1
+      elif is_first_parent_ancestor "$repository_path" "$left_sha" "$right_sha"; then
+        add_edge "$j" "$i"
+        strict_edges["${j},${i}"]=1
+      fi
+    done
+  done
+done
+
+# Strict evidence validates an uncertain candidate only when it connects to a
+# branch already observed directly on a stack. Propagate that proof through a
+# chain of strict first-parent relationships.
+proof_changed=true
+while [[ $proof_changed == true ]]; do
+  proof_changed=false
+  for edge in "${!strict_edges[@]}"; do
+    newer_index=${edge%,*}
+    older_index=${edge#*,}
+    if [[ ${candidate_proven[$newer_index]:-false} == true &&
+      ${candidate_proven[$older_index]:-false} != true ]]; then
+      candidate_proven[$older_index]=true
+      proof_changed=true
+    fi
+  done
+done
+
+# Compute transitive closure and reject contradictory evidence.
+for ((k = 0; k < candidate_count; k++)); do
+  for ((i = 0; i < candidate_count; i++)); do
+    [[ -n ${edges["${i},${k}"]+yes} ]] || continue
+    for ((j = 0; j < candidate_count; j++)); do
+      if [[ -n ${edges["${k},${j}"]+yes} ]]; then
+        edges["${i},${j}"]=1
+      fi
+    done
+  done
+done
+
+for ((i = 0; i < candidate_count; i++)); do
+  if [[ -n ${edges["${i},${i}"]+yes} ]]; then
+    echo "Contradictory branch ordering evidence involves '${candidates[$i]}'" >&2
+    exit 1
+  fi
+done
+
+for ((dependency_index = 0; dependency_index < ${#dependency_repositories[@]}; dependency_index++)); do
+  prefix=${dependency_prefixes[$dependency_index]}
+  repository=${dependency_repositories[$dependency_index]}
+  repository_path=${cloned_paths[$repository]}
+
+  default_branch=$(git -C "$repository_path" symbolic-ref --short HEAD)
+  default_branch=${default_branch#refs/heads/}
+
+  declare -a available_indices=()
+  declare -A available_shas=()
+  for ((i = 0; i < candidate_count; i++)); do
+    branch=${candidates[$i]}
+    sha=$(git -C "$repository_path" rev-parse --verify "refs/heads/${branch}^{commit}" 2>/dev/null || true)
+    if [[ -n $sha ]]; then
+      available_indices+=("$i")
+      available_shas[$i]=$sha
+    fi
+  done
+
+  declare -a newest_indices=()
+
+  # A merge-base-only branch may be a moved parent or an unrelated sibling.
+  # Without strict evidence elsewhere, selecting its distinct commit would be
+  # a guess. Equal target SHAs remain harmless aliases.
+  for i in "${available_indices[@]}"; do
+    [[ ${candidate_proven[$i]:-false} == true ]] && continue
+    harmless_uncertain=false
+    for j in "${available_indices[@]}"; do
+      if [[ ${candidate_proven[$j]:-false} == true &&
+        ( ${available_shas[$j]} == "${available_shas[$i]}" ||
+          -n ${edges["${j},${i}"]+yes} ) ]]; then
+        harmless_uncertain=true
+        break
+      fi
+    done
+    if [[ $harmless_uncertain != true ]]; then
+      echo "Cannot place shared branch '${candidates[$i]}' in the stack for ${repository}" >&2
+      exit 1
+    fi
+  done
+
+  for i in "${available_indices[@]}"; do
+    dominated=false
+    for j in "${available_indices[@]}"; do
+      if [[ $i != "$j" && -n ${edges["${j},${i}"]+yes} ]]; then
+        dominated=true
+        break
+      fi
+    done
+    [[ $dominated == true ]] || newest_indices+=("$i")
+  done
+
+  if (( ${#newest_indices[@]} == 0 )); then
+    echo "None of the candidate branches exists in ${repository}" >&2
+    exit 1
+  fi
+
+  selected_index=${newest_indices[0]}
+  selected_sha=${available_shas[$selected_index]}
+  if (( ${#newest_indices[@]} > 1 )); then
+    ambiguous=()
+    for i in "${newest_indices[@]}"; do
+      ambiguous+=("${candidates[$i]}")
+      if [[ ${available_shas[$i]} != "$selected_sha" ]]; then
+        printf -v ambiguous_list '%s, ' "${ambiguous[@]}"
+        ambiguous_list=${ambiguous_list%, }
+        echo "Ambiguous newest branches in ${repository}: ${ambiguous_list}" >&2
+        exit 1
+      fi
+    done
+  fi
+
+  selected_branch=${candidates[$selected_index]}
+  echo "Using '${selected_branch}' (${selected_sha}) for ${repository}"
+  {
+    echo "${prefix}_ref=${selected_sha}"
+    echo "${prefix}_branch=${selected_branch}"
+    echo "${prefix}_default=${default_branch}"
+  } >> "${GITHUB_OUTPUT:?GITHUB_OUTPUT is not set}"
+done
diff --git a/.github/scripts/test-resolve-dependency-refs.sh b/.github/scripts/test-resolve-dependency-refs.sh
new file mode 100644
index 000000000..a235f1c8e
--- /dev/null
+++ b/.github/scripts/test-resolve-dependency-refs.sh
@@ -0,0 +1,239 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+script_directory=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
+resolver=${1:-"${script_directory}/resolve-dependency-refs.sh"}
+test_directory=$(mktemp -d)
+source_repository="${test_directory}/source"
+
+git init --quiet --initial-branch=master "$source_repository"
+git -C "$source_repository" config user.name "CI Resolver Test"
+git -C "$source_repository" config user.email "ci-resolver@example.invalid"
+
+commit() {
+  local message=$1
+  git -C "$source_repository" commit --quiet --allow-empty -m "$message"
+}
+
+commit "master base"
+
+git -C "$source_repository" switch --quiet -c staging
+commit "staging base"
+
+git -C "$source_repository" switch --quiet -c lmsousa
+commit "branch A"
+lmsousa_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet -c vitest
+commit "branch B"
+vitest_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet -c java-deprecation
+commit "branch C"
+java_deprecation_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet -c workflow-fix
+commit "current branch"
+workflow_fix_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+# Both long-lived branches advance after the stack was created.
+git -C "$source_repository" switch --quiet staging
+commit "advanced staging"
+staging_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet master
+commit "advanced master"
+master_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+# Simulate a later push after the workflow event was created. Resolution must
+# use the detached event commit, never the newer remote source branch tip.
+git -C "$source_repository" switch --quiet workflow-fix
+commit "post-event parent branch"
+later_parent_tip=$(git -C "$source_repository" rev-parse HEAD)
+git -C "$source_repository" branch later-parent
+commit "post-event source update"
+post_event_source_tip=$(git -C "$source_repository" rev-parse HEAD)
+git -C "$source_repository" switch --quiet --detach "$workflow_fix_tip"
+
+git -C "$source_repository" switch --quiet lmsousa
+commit "advanced parent branch"
+advanced_lmsousa_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet staging
+git -C "$source_repository" switch --quiet -c rebased-parent-fixture
+commit "rebased parent branch"
+rebased_lmsousa_tip=$(git -C "$source_repository" rev-parse HEAD)
+
+git -C "$source_repository" switch --quiet --detach "$lmsousa_tip"
+git -C "$source_repository" switch --quiet -c unrelated-sibling
+commit "unrelated sibling branch"
+unrelated_sibling_tip=$(git -C "$source_repository" rev-parse HEAD)
+git -C "$source_repository" switch --quiet --detach "$workflow_fix_tip"
+
+for branch in workflow-fix java-deprecation vitest lmsousa staging master; do
+  branch_variable=${branch//-/_}_tip
+  git -C "$source_repository" update-ref \
+    "refs/remotes/origin/${branch}" "${!branch_variable}"
+done
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/workflow-fix "$post_event_source_tip"
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/later-parent "$later_parent_tip"
+# Clava's vitest and java-deprecation refs are intentionally equal. Another
+# repository must provide their strict ordering.
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/vitest "$java_deprecation_tip"
+
+make_dependency() {
+  local name=$1
+  shift
+  local repository="${test_directory}/${name}.git"
+
+  git clone --quiet --bare "$source_repository" "$repository"
+  while IFS= read -r ref; do
+    git -C "$repository" update-ref -d "$ref"
+  done < <(git -C "$repository" for-each-ref --format='%(refname)' refs/heads)
+
+  git -C "$repository" update-ref refs/heads/master "$master_tip"
+  for branch in "$@"; do
+    branch_variable=${branch//-/_}_tip
+    git -C "$repository" update-ref "refs/heads/${branch}" "${!branch_variable}"
+  done
+  git -C "$repository" symbolic-ref HEAD refs/heads/master
+  echo "$repository"
+}
+
+current_dependency=$(make_dependency current workflow-fix lmsousa)
+middle_dependency=$(make_dependency middle java-deprecation vitest lmsousa)
+older_dependency=$(make_dependency older vitest lmsousa)
+integration_dependency=$(make_dependency integration staging)
+root_dependency=$(make_dependency root)
+equal_dependency=$(make_dependency equal java-deprecation vitest lmsousa)
+git -C "$equal_dependency" update-ref \
+  refs/heads/vitest "$java_deprecation_tip"
+ambiguous_dependency=$(make_dependency ambiguous java-deprecation vitest lmsousa)
+git -C "$ambiguous_dependency" update-ref \
+  refs/heads/vitest "$staging_tip"
+reverse_dependency=$(make_dependency reverse java-deprecation vitest lmsousa)
+git -C "$reverse_dependency" update-ref \
+  refs/heads/java-deprecation "$vitest_tip"
+git -C "$reverse_dependency" update-ref \
+  refs/heads/vitest "$java_deprecation_tip"
+advanced_dependency=$(make_dependency advanced lmsousa staging)
+git -C "$advanced_dependency" update-ref \
+  refs/heads/lmsousa "$advanced_lmsousa_tip"
+rebased_dependency=$(make_dependency rebased lmsousa staging)
+git -C "$rebased_dependency" update-ref \
+  refs/heads/lmsousa "$rebased_lmsousa_tip"
+sibling_dependency=$(make_dependency sibling unrelated-sibling staging)
+
+output_file="${test_directory}/github-output"
+log_file="${test_directory}/resolver.log"
+SOURCE_BRANCH=workflow-fix GITHUB_OUTPUT="$output_file" \
+  bash "$resolver" "$source_repository" \
+    current "$current_dependency" \
+    middle "$middle_dependency" \
+    older "$older_dependency" \
+    integration "$integration_dependency" \
+    root "$root_dependency" |
+  tee "$log_file"
+
+grep -Fqx \
+  "Dependency branch candidates: workflow-fix -> java-deprecation -> vitest -> lmsousa -> staging -> master" \
+  "$log_file"
+if grep -Fq "later-parent" "$log_file"; then
+  echo "Resolver used a branch created after the workflow event" >&2
+  exit 1
+fi
+grep -Fqx "current_branch=workflow-fix" "$output_file"
+grep -Fqx "current_ref=${workflow_fix_tip}" "$output_file"
+grep -Fqx "middle_branch=java-deprecation" "$output_file"
+grep -Fqx "middle_ref=${java_deprecation_tip}" "$output_file"
+grep -Fqx "older_branch=vitest" "$output_file"
+grep -Fqx "older_ref=${vitest_tip}" "$output_file"
+grep -Fqx "integration_branch=staging" "$output_file"
+grep -Fqx "integration_ref=${staging_tip}" "$output_file"
+grep -Fqx "root_branch=master" "$output_file"
+grep -Fqx "root_ref=${master_tip}" "$output_file"
+
+# Equal, unordered names are safe when they resolve to the same target commit.
+equal_output="${test_directory}/equal-output"
+SOURCE_BRANCH=workflow-fix GITHUB_OUTPUT="$equal_output" \
+  bash "$resolver" "$source_repository" \
+    equal "$equal_dependency" >/dev/null
+grep -Fqx "equal_ref=${java_deprecation_tip}" "$equal_output"
+
+# Diverged candidates with no ordering evidence must fail rather than guess.
+if SOURCE_BRANCH=workflow-fix GITHUB_OUTPUT="${test_directory}/ambiguous-output" \
+  bash "$resolver" "$source_repository" \
+    ambiguous "$ambiguous_dependency" \
+    >"${test_directory}/ambiguous.log" 2>&1; then
+  echo "Resolver accepted ambiguous, different dependency refs" >&2
+  exit 1
+fi
+grep -Fq "Ambiguous newest branches" "${test_directory}/ambiguous.log"
+
+# Opposite strict orderings from two repositories are contradictory.
+if SOURCE_BRANCH=workflow-fix GITHUB_OUTPUT="${test_directory}/contradictory-output" \
+  bash "$resolver" "$source_repository" \
+    forward "$middle_dependency" \
+    reverse "$reverse_dependency" \
+    >"${test_directory}/contradictory.log" 2>&1; then
+  echo "Resolver accepted contradictory repository evidence" >&2
+  exit 1
+fi
+grep -Fq "Contradictory branch ordering evidence" \
+  "${test_directory}/contradictory.log"
+
+# Terminal branch workflows must not create a staging/master ordering cycle.
+git -C "$source_repository" switch --quiet --detach "$staging_tip"
+SOURCE_BRANCH=staging GITHUB_OUTPUT="${test_directory}/staging-output" \
+  bash "$resolver" "$source_repository" \
+    integration "$integration_dependency" >/dev/null
+grep -Fqx "integration_ref=${staging_tip}" \
+  "${test_directory}/staging-output"
+
+git -C "$source_repository" switch --quiet --detach "$master_tip"
+SOURCE_BRANCH=master GITHUB_OUTPUT="${test_directory}/master-output" \
+  bash "$resolver" "$source_repository" \
+    root "$root_dependency" >/dev/null
+grep -Fqx "root_ref=${master_tip}" "${test_directory}/master-output"
+
+# A shared parent remains a candidate when its tip advances or is rebased,
+# provided its merge-base still identifies this post-master stack.
+git -C "$source_repository" switch --quiet --detach "$workflow_fix_tip"
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/lmsousa "$advanced_lmsousa_tip"
+SOURCE_BRANCH=workflow-fix EVIDENCE_REPOSITORIES="$middle_dependency" \
+  GITHUB_OUTPUT="${test_directory}/advanced-output" \
+  bash "$resolver" "$source_repository" \
+    advanced "$advanced_dependency" >/dev/null
+grep -Fqx "advanced_ref=${advanced_lmsousa_tip}" \
+  "${test_directory}/advanced-output"
+
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/lmsousa "$rebased_lmsousa_tip"
+SOURCE_BRANCH=workflow-fix EVIDENCE_REPOSITORIES="$middle_dependency" \
+  GITHUB_OUTPUT="${test_directory}/rebased-output" \
+  bash "$resolver" "$source_repository" \
+    rebased "$rebased_dependency" >/dev/null
+grep -Fqx "rebased_ref=${rebased_lmsousa_tip}" \
+  "${test_directory}/rebased-output"
+
+# A shared sibling with the same fork point is not a proven stack member.
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/lmsousa "$lmsousa_tip"
+git -C "$source_repository" update-ref \
+  refs/remotes/origin/unrelated-sibling "$unrelated_sibling_tip"
+if SOURCE_BRANCH=workflow-fix GITHUB_OUTPUT="${test_directory}/sibling-output" \
+  bash "$resolver" "$source_repository" \
+    sibling "$sibling_dependency" \
+    >"${test_directory}/sibling.log" 2>&1; then
+  echo "Resolver selected an unproven sibling branch" >&2
+  exit 1
+fi
+grep -Fq "Cannot place shared branch 'unrelated-sibling'" \
+  "${test_directory}/sibling.log"
+
+echo "All dependency ref resolver tests passed"
diff --git a/.github/workflows/copilot-setup-steps.yml b/.github/workflows/copilot-setup-steps.yml
index d6a802310..b6c2c1cff 100644
--- a/.github/workflows/copilot-setup-steps.yml
+++ b/.github/workflows/copilot-setup-steps.yml
@@ -9,9 +9,13 @@ on:
   push:
     paths:
       - .github/workflows/copilot-setup-steps.yml
+      - .github/scripts/resolve-dependency-refs.sh
+      - .github/scripts/test-resolve-dependency-refs.sh
   pull_request:
     paths:
       - .github/workflows/copilot-setup-steps.yml
+      - .github/scripts/resolve-dependency-refs.sh
+      - .github/scripts/test-resolve-dependency-refs.sh
 
 env:
   BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
@@ -46,62 +50,31 @@ jobs:
         uses: actions/checkout@v6
         with:
           path: clava
+          fetch-depth: 0
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
+
+      - name: Test dependency ref resolver
+        run: bash clava/.github/scripts/test-resolve-dependency-refs.sh
 
       - name: Determine repository refs
         id: repo-refs
         shell: bash
         env:
-          BRANCH_NAME: ${{ env.BRANCH_NAME }}
-          BASE_BRANCH: ${{ github.base_ref }}
+          SOURCE_BRANCH: ${{ env.BRANCH_NAME }}
         run: |
-          set -euo pipefail
-
-          # For each dependency repository, determine which branch to checkout.
-          # Priority order:
-          # 1. A branch with the same name as the current branch
-          # 2. If this is a PR, the target branch (base_ref)
-          # 3. The default branch of the repository
-
-          determine_ref() {
-            local prefix=$1
-            local repo=$2
-            local url="https://github.com/${repo}.git"
-
-            # Get the default branch
-            local default_branch
-            default_branch=$(git ls-remote --symref "$url" HEAD | awk '/^ref:/ {print $2}' | sed 's@refs/heads/@@')
-            echo "${prefix}_default=${default_branch}" >> "$GITHUB_OUTPUT"
-            echo "Default branch for ${repo} is '${default_branch}'"
-
-            local ref_to_use=""
-            
-            # Priority 1: Same branch name
-            if [ -n "$(git ls-remote --heads "$url" "refs/heads/${BRANCH_NAME}")" ]; then
-              ref_to_use="${BRANCH_NAME}"
-              echo "Using matching branch '${BRANCH_NAME}' in ${repo}"
-            # Priority 2: PR target branch (if this is a PR)
-            elif [ -n "${BASE_BRANCH}" ] && [ -n "$(git ls-remote --heads "$url" "refs/heads/${BASE_BRANCH}")" ]; then
-              ref_to_use="${BASE_BRANCH}"
-              echo "Using PR target branch '${BASE_BRANCH}' in ${repo}"
-            # Priority 3: Default branch
-            else
-              ref_to_use="${default_branch}"
-              echo "Using default branch '${default_branch}' for ${repo}"
-            fi
-            
-            echo "${prefix}_ref=${ref_to_use}" >> "$GITHUB_OUTPUT"
-          }
-
-          determine_ref "lara" "specs-feup/lara-framework"
-          determine_ref "specs" "specs-feup/specs-java-libs"
+          bash clava/.github/scripts/resolve-dependency-refs.sh \
+            clava \
+            lara specs-feup/lara-framework \
+            specs specs-feup/specs-java-libs
 
       - name: Echo checks
         run: |
           echo "Weaver branch: ${{ env.BRANCH_NAME }}"
-          echo "PR target branch (if any): ${{ github.base_ref }}"
-          echo "Lara framework ref: ${{ steps.repo-refs.outputs.lara_ref }}"
+          echo "Lara framework branch: ${{ steps.repo-refs.outputs.lara_branch }}"
+          echo "Lara framework commit: ${{ steps.repo-refs.outputs.lara_ref }}"
           echo "Lara framework default: ${{ steps.repo-refs.outputs.lara_default }}"
-          echo "Specs-java-libs ref: ${{ steps.repo-refs.outputs.specs_ref }}"
+          echo "Specs-java-libs branch: ${{ steps.repo-refs.outputs.specs_branch }}"
+          echo "Specs-java-libs commit: ${{ steps.repo-refs.outputs.specs_ref }}"
           echo "Specs-java-libs default: ${{ steps.repo-refs.outputs.specs_default }}"
 
       - name: Checkout lara-framework
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 98915e2b0..f4e09490e 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -7,6 +7,7 @@ name: nightly
 
 on:
   push:
+  pull_request:
 
   # Daily at midnight
   schedule:
@@ -46,62 +47,31 @@ jobs:
         uses: actions/checkout@v6
         with:
           path: clava
+          fetch-depth: 0
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
+
+      - name: Test dependency ref resolver
+        run: bash clava/.github/scripts/test-resolve-dependency-refs.sh
 
       - name: Determine repository refs
         id: repo-refs
         shell: bash
         env:
-          BRANCH_NAME: ${{ env.BRANCH_NAME }}
-          BASE_BRANCH: ${{ github.base_ref }}
+          SOURCE_BRANCH: ${{ env.BRANCH_NAME }}
         run: |
-          set -euo pipefail
-
-          # For each dependency repository, determine which branch to checkout.
-          # Priority order:
-          # 1. A branch with the same name as the current branch
-          # 2. If this is a PR, the target branch (base_ref)
-          # 3. The default branch of the repository
-
-          determine_ref() {
-            local prefix=$1
-            local repo=$2
-            local url="https://github.com/${repo}.git"
-
-            # Get the default branch
-            local default_branch
-            default_branch=$(git ls-remote --symref "$url" HEAD | awk '/^ref:/ {print $2}' | sed 's@refs/heads/@@')
-            echo "${prefix}_default=${default_branch}" >> "$GITHUB_OUTPUT"
-            echo "Default branch for ${repo} is '${default_branch}'"
-
-            local ref_to_use=""
-            
-            # Priority 1: Same branch name
-            if [ -n "$(git ls-remote --heads "$url" "refs/heads/${BRANCH_NAME}")" ]; then
-              ref_to_use="${BRANCH_NAME}"
-              echo "Using matching branch '${BRANCH_NAME}' in ${repo}"
-            # Priority 2: PR target branch (if this is a PR)
-            elif [ -n "${BASE_BRANCH}" ] && [ -n "$(git ls-remote --heads "$url" "refs/heads/${BASE_BRANCH}")" ]; then
-              ref_to_use="${BASE_BRANCH}"
-              echo "Using PR target branch '${BASE_BRANCH}' in ${repo}"
-            # Priority 3: Default branch
-            else
-              ref_to_use="${default_branch}"
-              echo "Using default branch '${default_branch}' for ${repo}"
-            fi
-            
-            echo "${prefix}_ref=${ref_to_use}" >> "$GITHUB_OUTPUT"
-          }
-
-          determine_ref "lara" "specs-feup/lara-framework"
-          determine_ref "specs" "specs-feup/specs-java-libs"
+          bash clava/.github/scripts/resolve-dependency-refs.sh \
+            clava \
+            lara specs-feup/lara-framework \
+            specs specs-feup/specs-java-libs
 
       - name: Echo checks
         run: |
           echo "Weaver branch: ${{ env.BRANCH_NAME }}"
-          echo "PR target branch (if any): ${{ github.base_ref }}"
-          echo "Lara framework ref: ${{ steps.repo-refs.outputs.lara_ref }}"
+          echo "Lara framework branch: ${{ steps.repo-refs.outputs.lara_branch }}"
+          echo "Lara framework commit: ${{ steps.repo-refs.outputs.lara_ref }}"
           echo "Lara framework default: ${{ steps.repo-refs.outputs.lara_default }}"
-          echo "Specs-java-libs ref: ${{ steps.repo-refs.outputs.specs_ref }}"
+          echo "Specs-java-libs branch: ${{ steps.repo-refs.outputs.specs_branch }}"
+          echo "Specs-java-libs commit: ${{ steps.repo-refs.outputs.specs_ref }}"
           echo "Specs-java-libs default: ${{ steps.repo-refs.outputs.specs_default }}"
 
       - name: Checkout lara-framework
diff --git a/Clava-JS/api/SourceLocations.test.ts b/Clava-JS/api/SourceLocations.test.ts
index d2d06f95a..c805d530c 100644
--- a/Clava-JS/api/SourceLocations.test.ts
+++ b/Clava-JS/api/SourceLocations.test.ts
@@ -1,4 +1,4 @@
-import { registerSourceCode } from "@specs-feup/lara/jest/jestHelpers.ts";
+import { registerSourceCode } from "@specs-feup/lara/vitest/weaverTestHelpers.ts";
 import Query from "@specs-feup/lara/api/weaver/Query.ts";
 import { Joinpoint, Vardecl } from "./Joinpoints.ts";