From 4d3257995b2f2f4681aa41a3ec167238345bbde1 Mon Sep 17 00:00:00 2001
From: Conrad Kramer <conrad@conradkramer.com>
Date: Sat, 18 Apr 2026 19:10:18 -0700
Subject: [PATCH] Add Authentik SSO apps for Linear and 1Password

---
 Scripts/authentik-sync-1password-oidc.sh      | 243 +++++++++++++
 Scripts/authentik-sync-linear-saml.sh         | 334 ++++++++++++++++++
 ...ntik-backed-team-chat-and-workspace-sso.md | 152 ++++++++
 nixos/hosts/burrow-forge/default.nix          |   3 +
 nixos/modules/burrow-authentik.nix            | 153 ++++++++
 5 files changed, 885 insertions(+)
 create mode 100755 Scripts/authentik-sync-1password-oidc.sh
 create mode 100755 Scripts/authentik-sync-linear-saml.sh
 create mode 100644 evolution/proposals/BEP-0008-authentik-backed-team-chat-and-workspace-sso.md

diff --git a/Scripts/authentik-sync-1password-oidc.sh b/Scripts/authentik-sync-1password-oidc.sh
new file mode 100755
index 0000000..f523d9a
--- /dev/null
+++ b/Scripts/authentik-sync-1password-oidc.sh
@@ -0,0 +1,243 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+authentik_url="${AUTHENTIK_URL:-https://auth.burrow.net}"
+bootstrap_token="${AUTHENTIK_BOOTSTRAP_TOKEN:-}"
+application_slug="${AUTHENTIK_ONEPASSWORD_APPLICATION_SLUG:-onepassword}"
+application_name="${AUTHENTIK_ONEPASSWORD_APPLICATION_NAME:-1Password}"
+provider_name="${AUTHENTIK_ONEPASSWORD_PROVIDER_NAME:-1Password}"
+template_slug="${AUTHENTIK_ONEPASSWORD_TEMPLATE_SLUG:-ts}"
+client_id="${AUTHENTIK_ONEPASSWORD_CLIENT_ID:-1password.burrow.net}"
+launch_url="${AUTHENTIK_ONEPASSWORD_LAUNCH_URL:-https://burrow-team.1password.com/}"
+redirect_uris_json="${AUTHENTIK_ONEPASSWORD_REDIRECT_URIS_JSON:-[
+  \"https://burrow-team.1password.com/sso/oidc/redirect/\",
+  \"onepassword://sso/oidc/redirect\"
+]}"
+
+usage() {
+  cat <<'EOF'
+Usage: Scripts/authentik-sync-1password-oidc.sh
+
+Required environment:
+  AUTHENTIK_BOOTSTRAP_TOKEN
+
+Optional environment:
+  AUTHENTIK_URL
+  AUTHENTIK_ONEPASSWORD_APPLICATION_SLUG
+  AUTHENTIK_ONEPASSWORD_APPLICATION_NAME
+  AUTHENTIK_ONEPASSWORD_PROVIDER_NAME
+  AUTHENTIK_ONEPASSWORD_TEMPLATE_SLUG
+  AUTHENTIK_ONEPASSWORD_CLIENT_ID
+  AUTHENTIK_ONEPASSWORD_LAUNCH_URL
+  AUTHENTIK_ONEPASSWORD_REDIRECT_URIS_JSON
+EOF
+}
+
+if [[ "${1:-}" == "-h" || "${1:-}" == "--help" ]]; then
+  usage
+  exit 0
+fi
+
+if [[ -z "$bootstrap_token" ]]; then
+  echo "error: AUTHENTIK_BOOTSTRAP_TOKEN is required" >&2
+  exit 1
+fi
+
+if ! printf '%s' "$redirect_uris_json" | jq -e 'type == "array" and length > 0' >/dev/null; then
+  echo "error: AUTHENTIK_ONEPASSWORD_REDIRECT_URIS_JSON must be a non-empty JSON array" >&2
+  exit 1
+fi
+
+api() {
+  local method="$1"
+  local path="$2"
+  local data="${3:-}"
+
+  if [[ -n "$data" ]]; then
+    curl -fsS \
+      -X "$method" \
+      -H "Authorization: Bearer ${bootstrap_token}" \
+      -H "Content-Type: application/json" \
+      -d "$data" \
+      "${authentik_url}${path}"
+  else
+    curl -fsS \
+      -X "$method" \
+      -H "Authorization: Bearer ${bootstrap_token}" \
+      "${authentik_url}${path}"
+  fi
+}
+
+api_with_status() {
+  local method="$1"
+  local path="$2"
+  local data="${3:-}"
+  local response_file status
+
+  response_file="$(mktemp)"
+  trap 'rm -f "$response_file"' RETURN
+
+  if [[ -n "$data" ]]; then
+    status="$(
+      curl -sS \
+        -o "$response_file" \
+        -w '%{http_code}' \
+        -X "$method" \
+        -H "Authorization: Bearer ${bootstrap_token}" \
+        -H "Content-Type: application/json" \
+        -d "$data" \
+        "${authentik_url}${path}"
+    )"
+  else
+    status="$(
+      curl -sS \
+        -o "$response_file" \
+        -w '%{http_code}' \
+        -X "$method" \
+        -H "Authorization: Bearer ${bootstrap_token}" \
+        "${authentik_url}${path}"
+    )"
+  fi
+
+  printf '%s\n' "$status"
+  cat "$response_file"
+}
+
+wait_for_authentik() {
+  for _ in $(seq 1 90); do
+    if curl -fsS "${authentik_url}/-/health/ready/" >/dev/null 2>&1; then
+      return 0
+    fi
+    sleep 2
+  done
+
+  echo "error: Authentik did not become ready at ${authentik_url}" >&2
+  exit 1
+}
+
+wait_for_authentik
+
+template_provider="$(
+  api GET "/api/v3/providers/oauth2/?page_size=200" \
+    | jq -c --arg template_slug "$template_slug" '.results[]? | select(.assigned_application_slug == $template_slug)' \
+    | head -n1
+)"
+
+if [[ -z "$template_provider" ]]; then
+  echo "error: could not resolve the Authentik OAuth provider template ${template_slug}" >&2
+  exit 1
+fi
+
+authorization_flow="$(printf '%s\n' "$template_provider" | jq -r '.authorization_flow')"
+invalidation_flow="$(printf '%s\n' "$template_provider" | jq -r '.invalidation_flow')"
+property_mappings="$(printf '%s\n' "$template_provider" | jq -c '.property_mappings')"
+signing_key="$(printf '%s\n' "$template_provider" | jq -r '.signing_key')"
+
+provider_payload="$(
+  jq -n \
+    --arg name "$provider_name" \
+    --arg authorization_flow "$authorization_flow" \
+    --arg invalidation_flow "$invalidation_flow" \
+    --arg client_id "$client_id" \
+    --arg signing_key "$signing_key" \
+    --argjson property_mappings "$property_mappings" \
+    --argjson redirect_uris "$redirect_uris_json" \
+    '{
+      name: $name,
+      authorization_flow: $authorization_flow,
+      invalidation_flow: $invalidation_flow,
+      client_type: "public",
+      client_id: $client_id,
+      include_claims_in_id_token: true,
+      redirect_uris: ($redirect_uris | map({matching_mode: "strict", url: .})),
+      property_mappings: $property_mappings,
+      signing_key: $signing_key,
+      issuer_mode: "per_provider",
+      sub_mode: "hashed_user_id"
+    }'
+)"
+
+existing_provider="$(
+  api GET "/api/v3/providers/oauth2/?page_size=200" \
+    | jq -c \
+      --arg application_slug "$application_slug" \
+      --arg provider_name "$provider_name" \
+      '.results[]? | select(.assigned_application_slug == $application_slug or .name == $provider_name)' \
+    | head -n1
+)"
+
+if [[ -n "$existing_provider" ]]; then
+  provider_pk="$(printf '%s\n' "$existing_provider" | jq -r '.pk')"
+  api PATCH "/api/v3/providers/oauth2/${provider_pk}/" "$provider_payload" >/dev/null
+else
+  provider_pk="$(
+    api POST "/api/v3/providers/oauth2/" "$provider_payload" \
+      | jq -r '.pk // empty'
+  )"
+fi
+
+if [[ -z "${provider_pk:-}" ]]; then
+  echo "error: 1Password OIDC provider did not return a primary key" >&2
+  exit 1
+fi
+
+application_payload="$(
+  jq -n \
+    --arg name "$application_name" \
+    --arg slug "$application_slug" \
+    --arg provider "$provider_pk" \
+    --arg launch_url "$launch_url" \
+    '{
+      name: $name,
+      slug: $slug,
+      provider: ($provider | tonumber),
+      meta_launch_url: $launch_url,
+      open_in_new_tab: true,
+      policy_engine_mode: "any"
+    }'
+)"
+
+existing_application="$(
+  api GET "/api/v3/core/applications/?page_size=200" \
+    | jq -c --arg slug "$application_slug" '.results[]? | select(.slug == $slug)' \
+    | head -n1
+)"
+
+if [[ -n "$existing_application" ]]; then
+  application_pk="$(printf '%s\n' "$existing_application" | jq -r '.pk')"
+else
+  create_application_result="$(
+    api_with_status POST "/api/v3/core/applications/" "$application_payload"
+  )"
+  create_application_status="$(printf '%s\n' "$create_application_result" | sed -n '1p')"
+  create_application_body="$(printf '%s\n' "$create_application_result" | sed '1d')"
+
+  if [[ "$create_application_status" =~ ^20[01]$ ]]; then
+    application_pk="$(printf '%s\n' "$create_application_body" | jq -r '.pk // empty')"
+  elif [[ "$create_application_status" == "400" ]] && printf '%s\n' "$create_application_body" | jq -e '
+      (.slug // [] | index("Application with this slug already exists.")) != null
+      or (.provider // [] | index("Application with this provider already exists.")) != null
+    ' >/dev/null; then
+    application_pk="existing-duplicate"
+  else
+    printf '%s\n' "$create_application_body" >&2
+    echo "error: could not reconcile Authentik application ${application_slug}" >&2
+    exit 1
+  fi
+fi
+
+if [[ -z "${application_pk:-}" ]]; then
+  echo "error: 1Password OIDC application did not return a primary key" >&2
+  exit 1
+fi
+
+for _ in $(seq 1 30); do
+  if curl -fsS "${authentik_url}/application/o/${application_slug}/.well-known/openid-configuration" >/dev/null 2>&1; then
+    echo "Synced Authentik 1Password OIDC application ${application_slug} (${application_name})."
+    exit 0
+  fi
+  sleep 2
+done
+
+echo "warning: 1Password OIDC issuer document for ${application_slug} was not immediately readable; keeping reconciled config." >&2
+echo "Synced Authentik 1Password OIDC application ${application_slug} (${application_name})."
diff --git a/Scripts/authentik-sync-linear-saml.sh b/Scripts/authentik-sync-linear-saml.sh
new file mode 100755
index 0000000..9bead9f
--- /dev/null
+++ b/Scripts/authentik-sync-linear-saml.sh
@@ -0,0 +1,334 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+authentik_url="${AUTHENTIK_URL:-https://auth.burrow.net}"
+bootstrap_token="${AUTHENTIK_BOOTSTRAP_TOKEN:-}"
+application_slug="${AUTHENTIK_LINEAR_APPLICATION_SLUG:-linear}"
+application_name="${AUTHENTIK_LINEAR_APPLICATION_NAME:-Linear}"
+provider_name="${AUTHENTIK_LINEAR_PROVIDER_NAME:-Linear}"
+launch_url="${AUTHENTIK_LINEAR_LAUNCH_URL:-https://linear.app/burrownet}"
+acs_url="${AUTHENTIK_LINEAR_ACS_URL:-}"
+audience="${AUTHENTIK_LINEAR_AUDIENCE:-}"
+issuer="${AUTHENTIK_LINEAR_ISSUER:-${authentik_url}/application/saml/${application_slug}/metadata/}"
+default_relay_state="${AUTHENTIK_LINEAR_DEFAULT_RELAY_STATE:-}"
+
+usage() {
+  cat <<'EOF'
+Usage: Scripts/authentik-sync-linear-saml.sh
+
+Required environment:
+  AUTHENTIK_BOOTSTRAP_TOKEN
+  AUTHENTIK_LINEAR_ACS_URL
+  AUTHENTIK_LINEAR_AUDIENCE
+
+Optional environment:
+  AUTHENTIK_URL
+  AUTHENTIK_LINEAR_APPLICATION_SLUG
+  AUTHENTIK_LINEAR_APPLICATION_NAME
+  AUTHENTIK_LINEAR_PROVIDER_NAME
+  AUTHENTIK_LINEAR_LAUNCH_URL
+  AUTHENTIK_LINEAR_ISSUER
+  AUTHENTIK_LINEAR_DEFAULT_RELAY_STATE
+EOF
+}
+
+if [[ "${1:-}" == "-h" || "${1:-}" == "--help" ]]; then
+  usage
+  exit 0
+fi
+
+if [[ -z "$bootstrap_token" ]]; then
+  echo "error: AUTHENTIK_BOOTSTRAP_TOKEN is required" >&2
+  exit 1
+fi
+
+if [[ -z "$acs_url" ]]; then
+  echo "error: AUTHENTIK_LINEAR_ACS_URL is required" >&2
+  exit 1
+fi
+
+if [[ -z "$audience" ]]; then
+  echo "error: AUTHENTIK_LINEAR_AUDIENCE is required" >&2
+  exit 1
+fi
+
+api() {
+  local method="$1"
+  local path="$2"
+  local data="${3:-}"
+
+  if [[ -n "$data" ]]; then
+    curl -fsS \
+      -X "$method" \
+      -H "Authorization: Bearer ${bootstrap_token}" \
+      -H "Content-Type: application/json" \
+      -d "$data" \
+      "${authentik_url}${path}"
+  else
+    curl -fsS \
+      -X "$method" \
+      -H "Authorization: Bearer ${bootstrap_token}" \
+      "${authentik_url}${path}"
+  fi
+}
+
+api_with_status() {
+  local method="$1"
+  local path="$2"
+  local data="${3:-}"
+  local response_file status
+
+  response_file="$(mktemp)"
+  trap 'rm -f "$response_file"' RETURN
+
+  if [[ -n "$data" ]]; then
+    status="$(
+      curl -sS \
+        -o "$response_file" \
+        -w '%{http_code}' \
+        -X "$method" \
+        -H "Authorization: Bearer ${bootstrap_token}" \
+        -H "Content-Type: application/json" \
+        -d "$data" \
+        "${authentik_url}${path}"
+    )"
+  else
+    status="$(
+      curl -sS \
+        -o "$response_file" \
+        -w '%{http_code}' \
+        -X "$method" \
+        -H "Authorization: Bearer ${bootstrap_token}" \
+        "${authentik_url}${path}"
+    )"
+  fi
+
+  printf '%s\n' "$status"
+  cat "$response_file"
+}
+
+wait_for_authentik() {
+  for _ in $(seq 1 90); do
+    if curl -fsS "${authentik_url}/-/health/ready/" >/dev/null 2>&1; then
+      return 0
+    fi
+    sleep 2
+  done
+
+  echo "error: Authentik did not become ready at ${authentik_url}" >&2
+  exit 1
+}
+
+lookup_oauth_template_field() {
+  local field="$1"
+
+  api GET "/api/v3/providers/oauth2/?page_size=200" \
+    | jq -r --arg field "$field" '.results[]? | select(.assigned_application_slug == "ts") | .[$field]' \
+    | head -n1
+}
+
+reconcile_property_mapping() {
+  local name="$1"
+  local saml_name="$2"
+  local friendly_name="$3"
+  local expression="$4"
+  local payload existing_pk
+
+  payload="$(
+    jq -n \
+      --arg name "$name" \
+      --arg saml_name "$saml_name" \
+      --arg friendly_name "$friendly_name" \
+      --arg expression "$expression" \
+      '{
+        name: $name,
+        saml_name: $saml_name,
+        friendly_name: $friendly_name,
+        expression: $expression
+      }'
+  )"
+
+  existing_pk="$(
+    api GET "/api/v3/propertymappings/provider/saml/?page_size=200" \
+      | jq -r --arg name "$name" '.results[]? | select(.name == $name) | .pk' \
+      | head -n1
+  )"
+
+  if [[ -n "$existing_pk" ]]; then
+    api PATCH "/api/v3/propertymappings/provider/saml/${existing_pk}/" "$payload" >/dev/null
+    printf '%s\n' "$existing_pk"
+  else
+    api POST "/api/v3/propertymappings/provider/saml/" "$payload" | jq -r '.pk // empty'
+  fi
+}
+
+wait_for_authentik
+
+authorization_flow="$(lookup_oauth_template_field authorization_flow)"
+invalidation_flow="$(lookup_oauth_template_field invalidation_flow)"
+signing_kp="$(lookup_oauth_template_field signing_key)"
+
+if [[ -z "$authorization_flow" || -z "$invalidation_flow" || -z "$signing_kp" ]]; then
+  echo "error: could not resolve Authentik provider defaults from Burrow Tailnet template" >&2
+  exit 1
+fi
+
+email_mapping_pk="$(
+  reconcile_property_mapping \
+    "Burrow Linear SAML Email" \
+    "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress" \
+    "email" \
+    'return request.user.email'
+)"
+
+name_mapping_pk="$(
+  reconcile_property_mapping \
+    "Burrow Linear SAML Name" \
+    "name" \
+    "name" \
+    'return request.user.name or request.user.username'
+)"
+
+first_name_mapping_pk="$(
+  reconcile_property_mapping \
+    "Burrow Linear SAML First Name" \
+    "firstName" \
+    "firstName" \
+    $'parts = (request.user.name or "").split(" ", 1)\nif len(parts) > 0 and parts[0]:\n    return parts[0]\nreturn request.user.username'
+)"
+
+last_name_mapping_pk="$(
+  reconcile_property_mapping \
+    "Burrow Linear SAML Last Name" \
+    "lastName" \
+    "lastName" \
+    $'parts = (request.user.name or "").rsplit(" ", 1)\nif len(parts) == 2 and parts[1]:\n    return parts[1]\nreturn request.user.username'
+)"
+
+if [[ -z "$email_mapping_pk" || -z "$name_mapping_pk" || -z "$first_name_mapping_pk" || -z "$last_name_mapping_pk" ]]; then
+  echo "error: failed to reconcile Linear SAML property mappings" >&2
+  exit 1
+fi
+
+provider_payload="$(
+  jq -n \
+    --arg name "$provider_name" \
+    --arg authorization_flow "$authorization_flow" \
+    --arg invalidation_flow "$invalidation_flow" \
+    --arg acs_url "$acs_url" \
+    --arg audience "$audience" \
+    --arg issuer "$issuer" \
+    --arg signing_kp "$signing_kp" \
+    --arg default_relay_state "$default_relay_state" \
+    --arg name_id_mapping "$email_mapping_pk" \
+    --arg email_mapping "$email_mapping_pk" \
+    --arg name_mapping "$name_mapping_pk" \
+    --arg first_name_mapping "$first_name_mapping_pk" \
+    --arg last_name_mapping "$last_name_mapping_pk" \
+    '{
+      name: $name,
+      authorization_flow: $authorization_flow,
+      invalidation_flow: $invalidation_flow,
+      acs_url: $acs_url,
+      audience: $audience,
+      issuer: $issuer,
+      signing_kp: $signing_kp,
+      sign_assertion: true,
+      sign_response: true,
+      sp_binding: "post",
+      name_id_mapping: $name_id_mapping,
+      property_mappings: [
+        $email_mapping,
+        $name_mapping,
+        $first_name_mapping,
+        $last_name_mapping
+      ]
+    }
+    + (if $default_relay_state == "" then {} else {default_relay_state: $default_relay_state} end)'
+)"
+
+existing_provider="$(
+  api GET "/api/v3/providers/saml/?page_size=200" \
+    | jq -c \
+      --arg application_slug "$application_slug" \
+      --arg provider_name "$provider_name" \
+      '.results[]? | select(.assigned_application_slug == $application_slug or .name == $provider_name)' \
+    | head -n1
+)"
+
+if [[ -n "$existing_provider" ]]; then
+  provider_pk="$(printf '%s\n' "$existing_provider" | jq -r '.pk')"
+  api PATCH "/api/v3/providers/saml/${provider_pk}/" "$provider_payload" >/dev/null
+else
+  provider_pk="$(
+    api POST "/api/v3/providers/saml/" "$provider_payload" \
+      | jq -r '.pk // empty'
+  )"
+fi
+
+if [[ -z "${provider_pk:-}" ]]; then
+  echo "error: Linear SAML provider did not return a primary key" >&2
+  exit 1
+fi
+
+application_payload="$(
+  jq -n \
+    --arg name "$application_name" \
+    --arg slug "$application_slug" \
+    --arg provider "$provider_pk" \
+    --arg launch_url "$launch_url" \
+    '{
+      name: $name,
+      slug: $slug,
+      provider: ($provider | tonumber),
+      meta_launch_url: $launch_url,
+      open_in_new_tab: true,
+      policy_engine_mode: "any"
+    }'
+)"
+
+existing_application="$(
+  api GET "/api/v3/core/applications/?page_size=200" \
+    | jq -c --arg slug "$application_slug" '.results[]? | select(.slug == $slug)' \
+    | head -n1
+)"
+
+if [[ -n "$existing_application" ]]; then
+  application_pk="$(printf '%s\n' "$existing_application" | jq -r '.pk')"
+  api PATCH "/api/v3/core/applications/${application_pk}/" "$application_payload" >/dev/null
+else
+  create_application_result="$(
+    api_with_status POST "/api/v3/core/applications/" "$application_payload"
+  )"
+  create_application_status="$(printf '%s\n' "$create_application_result" | sed -n '1p')"
+  create_application_body="$(printf '%s\n' "$create_application_result" | sed '1d')"
+
+  if [[ "$create_application_status" =~ ^20[01]$ ]]; then
+    application_pk="$(printf '%s\n' "$create_application_body" | jq -r '.pk // empty')"
+  elif [[ "$create_application_status" == "400" ]] && printf '%s\n' "$create_application_body" | jq -e '
+      (.slug // [] | index("Application with this slug already exists.")) != null
+      or (.provider // [] | index("Application with this provider already exists.")) != null
+    ' >/dev/null; then
+    application_pk="existing-duplicate"
+  else
+    printf '%s\n' "$create_application_body" >&2
+    echo "error: could not reconcile Authentik application ${application_slug}" >&2
+    exit 1
+  fi
+fi
+
+if [[ -z "${application_pk:-}" ]]; then
+  echo "error: Linear SAML application did not return a primary key" >&2
+  exit 1
+fi
+
+for _ in $(seq 1 30); do
+  if curl -fsS "${authentik_url}/application/saml/${application_slug}/metadata/" >/dev/null 2>&1; then
+    echo "Synced Authentik Linear SAML application ${application_slug} (${application_name})."
+    exit 0
+  fi
+  sleep 2
+done
+
+echo "warning: Linear SAML metadata for ${application_slug} was not immediately readable; keeping reconciled config." >&2
+echo "Synced Authentik Linear SAML application ${application_slug} (${application_name})."
diff --git a/evolution/proposals/BEP-0008-authentik-backed-team-chat-and-workspace-sso.md b/evolution/proposals/BEP-0008-authentik-backed-team-chat-and-workspace-sso.md
new file mode 100644
index 0000000..6c11dbc
--- /dev/null
+++ b/evolution/proposals/BEP-0008-authentik-backed-team-chat-and-workspace-sso.md
@@ -0,0 +1,152 @@
+# `BEP-0008` - Authentik-Backed Team Chat and Workspace Identity
+
+```text
+Status: Draft
+Proposal: BEP-0008
+Authors: gpt-5.4
+Coordinator: gpt-5.4
+Reviewers: Pending
+Constitution Sections: II, III, V
+Implementation PRs: Pending
+Decision Date: Pending
+```
+
+## Summary
+
+Burrow should add a self-hosted team chat surface at `chat.burrow.net` and
+continue the project-wide move toward Authentik as the identity authority for
+external work systems. The immediate targets are a self-hosted Zulip
+deployment rooted in Authentik SAML, a Linear SAML configuration when the
+workspace plan supports it, and a 1Password Unlock-with-SSO deployment rooted
+in the same Authentik-backed OIDC authority.
+
+This keeps Burrow's day-to-day coordination surfaces aligned with the same
+admin groups, canonical users, and secret-handling model already used for
+Forgejo, Headscale, and Tailscale. It also avoids fragmenting login state
+across vendor-native Google auth flows when Burrow already operates an IdP.
+
+## Motivation
+
+- Forge, Tailnet, operator identity, and Tailscale custom OIDC are already
+  rooted in Authentik. Team chat, work tracking, and password-manager access
+  should not become separate authority islands.
+- Zulip provides a self-hosted chat system under Burrow's control, which fits
+  the constitution better than adding another hosted chat dependency.
+- Linear remains a SaaS dependency, but its workspace access should still be
+  derived from Burrow-managed identities and domains when the vendor plan
+  exposes SAML configuration.
+- 1Password Business is another external work surface where Burrow-controlled
+  identities are preferable to vendor-native Google-only auth. Its current
+  vendor flow is OIDC-based Unlock with SSO rather than SAML, so the proposal
+  needs to preserve protocol accuracy instead of flattening everything into
+  one SAML bucket.
+- Burrow already has a canonical public identity registry and a secret-backed
+  external-email alias map. Reusing that structure is lower-risk than
+  inventing per-app user bootstrap logic.
+
+## Detailed Design
+
+- Add a Burrow-managed Zulip workload on the forge host at `chat.burrow.net`.
+  The deployment should be repo-owned and rebuildable from Nix, even if the
+  runtime uses vendor-supported container images internally.
+- Zulip should authenticate through Authentik SAML rather than local passwords
+  as the primary path. Initial bootstrap may still keep an operational escape
+  hatch while the deployment is being validated.
+- Add Authentik-managed SAML applications for:
+  - Zulip at `chat.burrow.net`
+  - Linear using Burrow's claimed domains and Authentik metadata
+- Add an Authentik-managed OIDC application for 1Password Business under the
+  Burrow team sign-in address.
+- Treat Zulip and Linear as downstream applications of the same identity
+  authority, and treat 1Password as part of that same authority even though
+  its vendor protocol is OIDC rather than SAML. The source of truth remains:
+  - public identities and admin intent in `contributors.nix`
+  - private alias mappings and external accounts in agenix-encrypted secrets
+- Keep app-specific configuration in dedicated reconciliation code or module
+  options instead of hand-edited UI state.
+- Prefer service-specific reconciliation over ad hoc manual setup so rebuilds
+  and host replacement converge automatically.
+- Model 1Password according to the vendor's actual integration contract:
+  - OIDC Authorization Code Flow with PKCE
+  - public client rather than a confidential client
+  - no Burrow-side dependence on a stored client secret unless the vendor flow
+    changes
+
+## Security and Operational Considerations
+
+- Do not store external personal email mappings in public registry files.
+  Public tree data may include Burrow usernames and canonical `@burrow.net`
+  addresses, but external aliases must stay in encrypted secrets.
+- Zulip internal service credentials, Django secret material, and any mail
+  credentials must have explicit storage and rotation paths.
+- Linear SAML must not become Burrow's only admin recovery path. At least one
+  owner login path outside the enforced SAML flow should remain available until
+  rollout is proven.
+- 1Password Owners cannot be forced onto Unlock with SSO during initial setup.
+  Burrow should preserve the owner recovery path and treat OIDC rollout as a
+  scoped migration for non-owner users first.
+- If Zulip is deployed without production-grade outbound email at first, that
+  limitation must be documented and treated as an operational constraint, not a
+  hidden assumption.
+- Rollback should be straightforward:
+  - disable or stop the Zulip module
+  - remove the Authentik SAML apps
+  - remove the Authentik OIDC app used for 1Password if necessary
+  - leave the underlying Burrow identities unchanged
+
+## Contributor Playbook
+
+- Define the app and identity intent in the repository before modifying the
+  forge host.
+- Add or update Nix modules so `burrow-forge` can rebuild Zulip and the
+  corresponding Authentik SAML configuration from the tree.
+- Verify:
+  - `chat.burrow.net` serves a working Zulip login surface
+  - Authentik exposes working metadata for Zulip and Linear
+  - Authentik exposes a working OIDC issuer for 1Password
+  - users in Burrow admin groups receive the expected access on first login
+- Record concrete evidence for:
+  - host deployment generation
+  - Authentik reconciliation success
+  - Zulip login success
+  - Linear SAML configuration state
+  - 1Password Unlock with SSO configuration state
+
+## Alternatives Considered
+
+- Use Zulip Cloud instead of self-hosting. Rejected because the ask is to host
+  chat under `chat.burrow.net`, and Burrow already operates a forge host with a
+  self-managed identity plane.
+- Keep Linear on Google-native login. Rejected because it leaves Burrow work
+  access outside the project's operator and group model.
+- Treat 1Password as a SAML app for consistency. Rejected because the live
+  vendor flow is OIDC and Burrow should not pretend otherwise in repo-owned
+  infrastructure.
+- Add per-app manual Authentik configuration without repository automation.
+  Rejected because it violates Burrow's infrastructure-in-repo commitment.
+
+## Impact on Other Work
+
+- Extends Burrow's Authentik role from control-plane identity into team-work
+  surfaces.
+- Introduces a persistent chat workload on the forge host, with resource and
+  monitoring implications.
+- Creates a likely follow-up for SCIM or richer group synchronization if Linear
+  or Zulip role mapping needs to become fully declarative later.
+- Adds a second OIDC relying party beyond Forgejo, Headscale, and Tailscale,
+  which raises the importance of keeping Burrow's Authentik scope mappings and
+  redirect handling consistent across applications.
+
+## Decision
+
+Pending.
+
+## References
+
+- `CONSTITUTION.md`
+- `contributors.nix`
+- `evolution/proposals/BEP-0004-hosted-mail-and-saas-identity.md`
+- Authentik docs: SAML provider and metadata endpoints
+- Zulip docs: SAML authentication and docker deployment
+- Linear docs: SAML and access control
+- 1Password docs: Unlock with SSO using OpenID Connect
diff --git a/nixos/hosts/burrow-forge/default.nix b/nixos/hosts/burrow-forge/default.nix
index 96eca4f..3f73346 100644
--- a/nixos/hosts/burrow-forge/default.nix
+++ b/nixos/hosts/burrow-forge/default.nix
@@ -207,6 +207,9 @@ in
     userGroupName = contributors.groups.users;
     adminGroupName = contributors.groups.admins;
     bootstrapUsers = bootstrapUsers;
+    linearAcsUrl = "https://api.linear.app/auth/sso/d0ca13dc-ac41-4824-8aab-e0ca352fc3de/acs";
+    linearAudience = "https://auth.linear.app/sso/d0ca13dc-ac41-4824-8aab-e0ca352fc3de";
+    linearDefaultRelayState = "https://linear.app/auth/sso/d0ca13dc-ac41-4824-8aab-e0ca352fc3de";
   };
 
   services.burrow.headscale = {
diff --git a/nixos/modules/burrow-authentik.nix b/nixos/modules/burrow-authentik.nix
index 2fa83da..5b04de2 100644
--- a/nixos/modules/burrow-authentik.nix
+++ b/nixos/modules/burrow-authentik.nix
@@ -11,6 +11,8 @@ let
   directorySyncScript = ../../Scripts/authentik-sync-burrow-directory.sh;
   forgejoOidcSyncScript = ../../Scripts/authentik-sync-forgejo-oidc.sh;
   tailscaleOidcSyncScript = ../../Scripts/authentik-sync-tailscale-oidc.sh;
+  onePasswordOidcSyncScript = ../../Scripts/authentik-sync-1password-oidc.sh;
+  linearSamlSyncScript = ../../Scripts/authentik-sync-linear-saml.sh;
   googleSourceSyncScript = ../../Scripts/authentik-sync-google-source.sh;
   tailnetAuthFlowSyncScript = ../../Scripts/authentik-sync-tailnet-auth-flow.sh;
   authentikBlueprint = pkgs.writeText "burrow-authentik-blueprint.yaml" ''
@@ -150,6 +152,63 @@ in
       description = "Host-local file containing the Authentik Tailscale OIDC client secret.";
     };
 
+    onePasswordDomain = lib.mkOption {
+      type = lib.types.str;
+      default = "burrow-team.1password.com";
+      description = "1Password team sign-in domain used for Burrow Unlock with SSO.";
+    };
+
+    onePasswordProviderSlug = lib.mkOption {
+      type = lib.types.str;
+      default = "onepassword";
+      description = "Authentik application slug for 1Password Unlock with SSO.";
+    };
+
+    onePasswordClientId = lib.mkOption {
+      type = lib.types.str;
+      default = "1password.burrow.net";
+      description = "Public OIDC client ID Authentik should present to 1Password.";
+    };
+
+    onePasswordRedirectUris = lib.mkOption {
+      type = lib.types.listOf lib.types.str;
+      default = [
+        "https://burrow-team.1password.com/sso/oidc/redirect/"
+        "onepassword://sso/oidc/redirect"
+      ];
+      description = "Allowed 1Password OIDC redirect URIs.";
+    };
+
+    linearProviderSlug = lib.mkOption {
+      type = lib.types.str;
+      default = "linear";
+      description = "Authentik application slug for Linear SAML.";
+    };
+
+    linearAcsUrl = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = "Linear SAML ACS URL.";
+    };
+
+    linearAudience = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = "Linear SAML audience/entity identifier.";
+    };
+
+    linearLaunchUrl = lib.mkOption {
+      type = lib.types.str;
+      default = "https://linear.app/burrownet";
+      description = "Linear workspace URL exposed in Authentik.";
+    };
+
+    linearDefaultRelayState = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      description = "Optional Linear relay state or login URL for IdP-initiated launches.";
+    };
+
     forgejoClientId = lib.mkOption {
       type = lib.types.str;
       default = "git.burrow.net";
@@ -718,6 +777,100 @@ EOF
       '';
     };
 
+    systemd.services.burrow-authentik-1password-oidc = {
+      description = "Reconcile the Burrow Authentik 1Password OIDC application";
+      after = [
+        "burrow-authentik-ready.service"
+        "network-online.target"
+      ];
+      wants = [
+        "burrow-authentik-ready.service"
+        "network-online.target"
+      ];
+      wantedBy = [ "multi-user.target" ];
+      restartTriggers = [
+        onePasswordOidcSyncScript
+        cfg.envFile
+      ];
+      path = [
+        pkgs.bash
+        pkgs.coreutils
+        pkgs.curl
+        pkgs.jq
+      ];
+      serviceConfig = {
+        Type = "oneshot";
+        User = "root";
+        Group = "root";
+      };
+      script = ''
+        set -euo pipefail
+        set -a
+        source ${lib.escapeShellArg cfg.envFile}
+        set +a
+
+        export AUTHENTIK_URL=https://${cfg.domain}
+        export AUTHENTIK_ONEPASSWORD_APPLICATION_SLUG=${lib.escapeShellArg cfg.onePasswordProviderSlug}
+        export AUTHENTIK_ONEPASSWORD_APPLICATION_NAME=1Password
+        export AUTHENTIK_ONEPASSWORD_PROVIDER_NAME=1Password
+        export AUTHENTIK_ONEPASSWORD_TEMPLATE_SLUG=${lib.escapeShellArg cfg.headscaleProviderSlug}
+        export AUTHENTIK_ONEPASSWORD_CLIENT_ID=${lib.escapeShellArg cfg.onePasswordClientId}
+        export AUTHENTIK_ONEPASSWORD_LAUNCH_URL=https://${cfg.onePasswordDomain}/
+        export AUTHENTIK_ONEPASSWORD_REDIRECT_URIS_JSON='${builtins.toJSON cfg.onePasswordRedirectUris}'
+
+        ${pkgs.bash}/bin/bash ${onePasswordOidcSyncScript}
+      '';
+    };
+
+    systemd.services.burrow-authentik-linear-saml = lib.mkIf (
+      cfg.linearAcsUrl != null && cfg.linearAudience != null
+    ) {
+      description = "Reconcile the Burrow Authentik Linear SAML application";
+      after = [
+        "burrow-authentik-ready.service"
+        "network-online.target"
+      ];
+      wants = [
+        "burrow-authentik-ready.service"
+        "network-online.target"
+      ];
+      wantedBy = [ "multi-user.target" ];
+      restartTriggers = [
+        linearSamlSyncScript
+        cfg.envFile
+      ];
+      path = [
+        pkgs.bash
+        pkgs.coreutils
+        pkgs.curl
+        pkgs.jq
+      ];
+      serviceConfig = {
+        Type = "oneshot";
+        User = "root";
+        Group = "root";
+      };
+      script = ''
+        set -euo pipefail
+        set -a
+        source ${lib.escapeShellArg cfg.envFile}
+        set +a
+
+        export AUTHENTIK_URL=https://${cfg.domain}
+        export AUTHENTIK_LINEAR_APPLICATION_SLUG=${lib.escapeShellArg cfg.linearProviderSlug}
+        export AUTHENTIK_LINEAR_APPLICATION_NAME=Linear
+        export AUTHENTIK_LINEAR_PROVIDER_NAME=Linear
+        export AUTHENTIK_LINEAR_ACS_URL=${lib.escapeShellArg cfg.linearAcsUrl}
+        export AUTHENTIK_LINEAR_AUDIENCE=${lib.escapeShellArg cfg.linearAudience}
+        export AUTHENTIK_LINEAR_LAUNCH_URL=${lib.escapeShellArg cfg.linearLaunchUrl}
+        ${lib.optionalString (cfg.linearDefaultRelayState != null) ''
+          export AUTHENTIK_LINEAR_DEFAULT_RELAY_STATE=${lib.escapeShellArg cfg.linearDefaultRelayState}
+        ''}
+
+        ${pkgs.bash}/bin/bash ${linearSamlSyncScript}
+      '';
+    };
+
     services.caddy.virtualHosts."${cfg.domain}".extraConfig = ''
       encode gzip zstd
       reverse_proxy 127.0.0.1:${toString cfg.port}