feat(telemetry): track binary downloads and repo clones via PostHog

Add formae_track_event helper to run-conformance-tests.sh to send
ci_binary_download events after formae binary downloads. Add clone
tracking step to nightly workflows and pass POSTHOG_API_KEY to
conformance test steps. Gated on POSTHOG_API_KEY env var — silently
no-ops when unset.

Author: JeroenSoeters

.github/workflows/ci.yml

@@ -139,6 +139,7 @@ jobs:
           AZURE_SUBSCRIPTION_ID: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
           FORMAE_TEST_RUN_ID: ${{ github.run_id }}-${{ github.run_attempt }}-${{ matrix.resource }}
           FORMAE_TEST_FILTER: ${{ matrix.resource }}
+          POSTHOG_API_KEY: ${{ secrets.POSTHOG_API_KEY }}
         run: make conformance-test
 
   # Clean up Azure resources after all matrix jobs complete

.github/workflows/nightly.yml

@@ -90,6 +90,32 @@ jobs:
           make build
           echo "FORMAE_BINARY=/tmp/formae/formae" >> $GITHUB_ENV
 
+      - name: Track formae clone
+        if: env.POSTHOG_API_KEY != ''
+        env:
+          POSTHOG_API_KEY: ${{ secrets.POSTHOG_API_KEY }}
+        run: |
+          REPO=$(basename "$(git remote get-url origin)" .git 2>/dev/null || echo "unknown")
+          curl -sf -o /dev/null https://us.i.posthog.com/capture/ \
+            -H "Content-Type: application/json" \
+            -d "$(jq -n \
+              --arg api_key "$POSTHOG_API_KEY" \
+              --arg repo "$REPO" \
+              --arg ts "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
+              --arg run_id "${GITHUB_RUN_ID:-}" \
+              '{
+                api_key: $api_key,
+                distinct_id: "formae-ci",
+                event: "ci_repo_clone",
+                timestamp: $ts,
+                properties: {
+                  "$process_person_profile": false,
+                  repo: $repo,
+                  cloned_repo: "formae",
+                  ci_run_id: $run_id
+                }
+              }')" || echo "[telemetry] event send failed (non-critical)" >&2
+
       - name: Configure Azure Credentials
         uses: azure/login@v2
         with:
@@ -105,6 +131,7 @@ jobs:
           AZURE_SUBSCRIPTION_ID: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
           FORMAE_TEST_RUN_ID: nightly-main-${{ github.run_id }}-${{ matrix.resource }}
           FORMAE_TEST_FILTER: ${{ matrix.resource }}
+          POSTHOG_API_KEY: ${{ secrets.POSTHOG_API_KEY }}
         run: make conformance-test
 
   # Clean up Azure resources after all matrix jobs complete

scripts/run-conformance-tests.sh

@@ -27,6 +27,45 @@ sed_inplace() {
     fi
 }
 
+# Sends a telemetry event to PostHog for tracking CI/dev binary downloads.
+# Gated on POSTHOG_API_KEY — silently no-ops when unset.
+formae_track_event() {
+  local api_key="${POSTHOG_API_KEY:-}"
+  if [[ -z "$api_key" ]]; then return; fi
+
+  local event="$1"; shift
+  local repo
+  repo=$(basename "$(git remote get-url origin 2>/dev/null)" .git 2>/dev/null || echo "unknown")
+
+  local payload
+  payload=$(jq -n \
+    --arg api_key "$api_key" \
+    --arg event "$event" \
+    --arg repo "$repo" \
+    --arg ts "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
+    --arg run_id "${GITHUB_RUN_ID:-}" \
+    '{
+      api_key: $api_key,
+      distinct_id: "formae-ci",
+      event: $event,
+      timestamp: $ts,
+      properties: {
+        "$process_person_profile": false,
+        repo: $repo,
+        ci_run_id: $run_id
+      }
+    }')
+
+  for kv in "$@"; do
+    local key="${kv%%=*}" val="${kv#*=}"
+    payload=$(echo "$payload" | jq --arg k "$key" --arg v "$val" '.properties[$k] = $v')
+  done
+
+  curl -sf -o /dev/null https://us.i.posthog.com/capture/ \
+    -H "Content-Type: application/json" \
+    -d "$payload" || echo "[telemetry] event send failed (non-critical)" >&2 &
+}
+
 VERSION="${1:-latest}"
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROJECT_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
@@ -100,6 +139,8 @@ else
     fi
 fi
 
+formae_track_event "ci_binary_download" "version=${VERSION}" "os=${DETECTED_OS}" "arch=${DETECTED_ARCH}"
+
 echo ""
 echo "Using formae binary: ${FORMAE_BINARY}"
 "${FORMAE_BINARY}" --version