feat: publish Tend v0.2 Preview 2 source

Export the reviewed allowlisted snapshot from private source commit 8aab3db43f35e6a49aa497f45d73701b13fc9f32 and tree 992132ea4703437dc13ffdbb04a077816c02caf9. This includes routed singleton continuity, deployment evidence, strict schema-2 configuration, restricted transport, and the independently compilable public-tree guard.

AI-Assisted: OpenAI Codex
Signed-off-by: Cole Speelman <crspeelman@gmail.com>

examples/README.md

@@ -18,13 +18,24 @@ the isolated candidate address. Secret values never enter `tend.json`.
 The singleton example follows the same split: its shared root-only environment
 file omits the configured listen key, the installed unit owns the live address,
 and Tend supplies only the transient candidate address. This prevents a shared
-environment file from overriding the isolated candidate port.
+environment file from overriding the isolated candidate port. Its imported
+Caddy handler is also managed from one reviewed template. Tend temporarily
+routes the canonical origin to the proven candidate while the fixed-address
+unit restarts, then returns traffic to that unit only after it passes its local
+checks.
 
 Production configuration belongs outside the source checkout, owned by root,
 and not group- or world-writable. The Caddy handler template is an entire
 imported handler fragment; the enclosing site, matchers, and routing precedence
 remain operator-owned.
 
+`event_log` is a per-service, root-owned JSONL evidence stream below that
+service's release root. Grant an Observatory agent read access explicitly; do
+not make the release root broadly readable. `activation_window_seconds` keeps
+canonical routed probes active after Caddy reload and keeps the previous
+blue/green slot—or the singleton handoff candidate—under health/readiness
+observation until the activation is recorded.
+
 `server/` demonstrates the schema-2 receive policy, forced OpenSSH command,
 restricted sudo entry, two independent service configurations, and secret-file
 placement. The values are placeholders, not an installation script.

examples/blue-green/tend.json

@@ -7,9 +7,11 @@
     "root": "/opt/example-site",
     "lock_file": "/run/lock/tend-deploy.lock",
     "state_file": "/opt/example-site/tend-state.json",
+    "event_log": "/opt/example-site/deployment-events.jsonl",
     "health_path": "/healthz",
     "readiness_path": "/readyz",
     "candidate_timeout_seconds": 30,
+    "activation_window_seconds": 10,
     "smoke": [{ "path": "/", "contains": "Example site" }],
     "public_smoke": [{ "url": "https://example.test/", "contains": "Example site" }],
     "blue_green": {

examples/server/caddy/docs-site.template

@@ -0,0 +1,2 @@
+# Managed by Tend. The enclosing site and route matchers remain operator-owned.
+reverse_proxy {{UPSTREAM}}

examples/server/caddy/example-site.template

@@ -0,0 +1,2 @@
+# Managed by Tend. The enclosing site and route matchers remain operator-owned.
+reverse_proxy {{UPSTREAM}}

examples/server/services/docs-site.json

@@ -7,9 +7,11 @@
     "root": "/opt/docs-site",
     "lock_file": "/run/lock/tend-deploy.lock",
     "state_file": "/opt/docs-site/tend-state.json",
+    "event_log": "/opt/docs-site/deployment-events.jsonl",
     "health_path": "/healthz",
     "readiness_path": "/readyz",
     "candidate_timeout_seconds": 30,
+    "activation_window_seconds": 10,
     "smoke": [{ "path": "/", "contains": "Documentation" }],
     "public_smoke": [{ "url": "https://docs.example.test/", "contains": "Documentation" }],
     "singleton": {
@@ -18,7 +20,10 @@
       "candidate_address": "127.0.0.1:18102",
       "listen_env": "DOCS_LISTEN",
       "current_link": "/opt/docs-site/current",
-      "previous_link": "/opt/docs-site/previous"
+      "previous_link": "/opt/docs-site/previous",
+      "caddy_config": "/etc/caddy/Caddyfile",
+      "caddy_handler": "/etc/caddy/docs-site-handler.caddy",
+      "caddy_handler_template": "/etc/tend/caddy/docs-site.template"
     }
   }
 }

examples/server/services/example-site.json

@@ -7,9 +7,11 @@
     "root": "/opt/example-site",
     "lock_file": "/run/lock/tend-deploy.lock",
     "state_file": "/opt/example-site/tend-state.json",
+    "event_log": "/opt/example-site/deployment-events.jsonl",
     "health_path": "/healthz",
     "readiness_path": "/readyz",
     "candidate_timeout_seconds": 30,
+    "activation_window_seconds": 10,
     "smoke": [{ "path": "/", "contains": "Example site" }],
     "public_smoke": [{ "url": "https://example.test/", "contains": "Example site" }],
     "singleton": {
@@ -18,7 +20,10 @@
       "candidate_address": "127.0.0.1:18092",
       "listen_env": "EXAMPLE_LISTEN",
       "current_link": "/opt/example-site/current",
-      "previous_link": "/opt/example-site/previous"
+      "previous_link": "/opt/example-site/previous",
+      "caddy_config": "/etc/caddy/Caddyfile",
+      "caddy_handler": "/etc/caddy/example-site-handler.caddy",
+      "caddy_handler_template": "/etc/tend/caddy/example-site.template"
     }
   }
 }

examples/singleton/caddy-handler.template

@@ -0,0 +1,2 @@
+# Managed by Tend. The enclosing site and route matchers remain operator-owned.
+reverse_proxy {{UPSTREAM}}

examples/singleton/tend.json

@@ -7,9 +7,11 @@
     "root": "/opt/example-site",
     "lock_file": "/run/lock/tend-deploy.lock",
     "state_file": "/opt/example-site/tend-state.json",
+    "event_log": "/opt/example-site/deployment-events.jsonl",
     "health_path": "/healthz",
     "readiness_path": "/readyz",
     "candidate_timeout_seconds": 30,
+    "activation_window_seconds": 10,
     "smoke": [{ "path": "/", "contains": "Example site" }],
     "public_smoke": [{ "url": "https://example.test/", "contains": "Example site" }],
     "singleton": {
@@ -18,7 +20,10 @@
       "candidate_address": "127.0.0.1:18092",
       "listen_env": "EXAMPLE_LISTEN",
       "current_link": "/opt/example-site/current",
-      "previous_link": "/opt/example-site/previous"
+      "previous_link": "/opt/example-site/previous",
+      "caddy_config": "/etc/caddy/Caddyfile",
+      "caddy_handler": "/etc/caddy/example-site-handler.caddy",
+      "caddy_handler_template": "/etc/tend/caddy/example-site.template"
     }
   }
 }