FloWuenne · Oct 15, 2026 · Oct 1, 2026 · Oct 8, 2026 · Oct 15, 2026
diff --git a/README.md b/README.md
@@ -39,7 +39,7 @@ Below are detailed instructions for new users.
 
 ### Step 1: Install Nextflow
 
-First, ensure you have Java 11 or later installed, then install Nextflow:
+This pipeline requires Nextflow 26.04.0 or later. First, ensure you have Java 17 or later installed, then install Nextflow:
 
 ```bash
 # Install Nextflow
@@ -56,17 +56,7 @@ Verify the installation:
 nextflow -version
 ```
 
-You should see something like this:
-
-```console
->  nextflow -version
-
-      N E X T F L O W
-      version 25.04.6 build 5954
-      created 01-07-2025 11:27 UTC (12:27 BST)
-      cite doi:10.1038/nbt.3820
-      http://nextflow.io
-```
+Check that the reported version is 26.04.0 or later. Older versions stop with a version error before the pipeline starts.
 
 ### Step 2: Create a Seqera Platform Account
 

diff --git a/main.nf b/main.nf
@@ -4,19 +4,34 @@ include { ENTER_RAFFLE          } from './modules/local/enter_raffle/main'
 include { PRINT_PRIVACY_MESSAGE } from './modules/local/print_privacy_message/main'
 include { PUBLISH_REPORT        } from './modules/local/publish_report/main'
 
-workflow {
-    // Default event to ECCB 2026 if not specified
-    def event = params.event ?: 'eccb_2026'
+params {
+    help: Boolean = false
+    event: String = 'eccb_2026'
+    email: String = ''
+    affiliation: String = ''
+    first_name: String = ''
+    last_name: String = ''
+    outdir: String = 'results'
+    ticket_number_emit_session_id: Boolean = false
+}
 
+workflow {
+    main:
     // Validate required parameters
     if (!params.email) {
         error("Please provide --email parameter")
     }
 
-    // Load event configuration
-    def config_file = file("${projectDir}/event_configs/${event}.json", checkIfExists: true)
-
-    def config = new groovy.json.JsonSlurper().parse(config_file)
+    def config_file = file("${projectDir}/event_configs/${params.event}.json", checkIfExists: true)
+    def parsed = new groovy.json.JsonSlurper().parse(config_file)
+    def config = record(
+        event_name         : parsed.event_name,
+        help               : parsed.help,
+        destination_url    : parsed.destination_url,
+        form_fields        : parsed.form_fields,
+        required_fields    : parsed.required_fields,
+        winner_announcement: parsed.winner_announcement,
+    )
 
     // Validate participant-supplied fields this event marks as required. The
     // required_fields list is per-event, so other events are unaffected
@@ -31,72 +46,87 @@ workflow {
     ]
     config.required_fields?.each { fld ->
         if (required_field_params.containsKey(fld) && !required_field_params[fld]) {
-            error("This event (${event}) requires --${fld}")
+            error("This event (${params.event}) requires --${fld}")
         }
     }
 
-    // Print privacy policy information
-    PRINT_PRIVACY_MESSAGE(config)
-
-    // Standard raffle entry for all events
-    ENTER_RAFFLE(
-        PRINT_PRIVACY_MESSAGE.out,
-        params.email,
-        params.affiliation,
-        params.first_name,
-        params.last_name,
-        config
+    def ch_ready = PRINT_PRIVACY_MESSAGE(config)
+
+    // Read platform_enabled here (workflow.session.config is unavailable inside typed processes)
+    def platform_enabled = workflow.session.config.navigate('tower.enabled') ?: false
+
+    def participant = record(
+        email      : params.email,
+        first_name : params.first_name,
+        last_name  : params.last_name,
+        affiliation: params.affiliation,
+    )
+
+    def ch_participant = ch_ready.map { _ready -> participant }
+    def ch_entry = ENTER_RAFFLE(
+        ch_participant,
+        config,
+        platform_enabled
     )
 
-    // Generate ticket
-    html_report_template = Channel.fromPath("${projectDir}/assets/ticket_template.html")
-    event_name = config.event_name
-    ticket_number = params.ticket_number_emit_session_id ? ENTER_RAFFLE.out.session_id : ENTER_RAFFLE.out.run_name
+    def html_report_template = channel.fromPath("${projectDir}/assets/ticket_template.html")
+    def event_name = config.event_name
+    def ticket_number = params.ticket_number_emit_session_id
+        ? ch_entry.map { entry -> entry.session_id }
+        : ch_entry.map { entry -> entry.run_name }
+    def winner_announcement = config.winner_announcement ?: ""
 
-    winner_announcement = config.winner_announcement ?: ""
     PUBLISH_REPORT(html_report_template, event_name, ticket_number, winner_announcement)
 
-    workflow.onComplete = {
-        // Check if Tower/Platform is disabled or access token is missing
-        def towerEnabled = workflow.session.config.navigate('tower.enabled') ?: false
-        def towerToken = workflow.session.config.navigate('tower.accessToken') ?: System.getenv('TOWER_ACCESS_TOKEN')
+    publish:
+    raffle_ticket = PUBLISH_REPORT.out
 
-        if (!towerEnabled || !towerToken) {
-            log.warn """
-            =====================================
-            💡 Win more entries to the raffle! 💡
-            =====================================
+    onComplete:
+    def towerEnabled = workflow.session.config.navigate('tower.enabled') ?: false
+    def towerToken = workflow.session.config.navigate('tower.accessToken') ?: System.getenv('TOWER_ACCESS_TOKEN')
 
-            Create a free account on https://cloud.seqera.io/ to get additional raffle entries!
-            Simply enable Seqera Platform monitoring by:
+    if (!towerEnabled || !towerToken) {
+        log.warn """
+        =====================================
+        💡 Win more entries to the raffle! 💡
+        =====================================
 
-            1. Create an account on https://cloud.seqera.io/
+        Create a free account on https://cloud.seqera.io/ to get additional raffle entries!
+        Simply enable Seqera Platform monitoring by:
 
-            2. Create an access token at https://cloud.seqera.io/tokens
+        1. Create an account on https://cloud.seqera.io/
 
-            3. Adding to your nextflow.config:
-            tower {
-                enabled     = true
-                accessToken = 'your-token-here'
-            }
+        2. Create an access token at https://cloud.seqera.io/tokens
 
-            4. Run the pipeline with the additional configuration:
-            nextflow run seqeralabs/nf-raffle --email <your email> -c nextflow.config
+        3. Adding to your nextflow.config:
+        tower {
+            enabled     = true
+            accessToken = 'your-token-here'
+        }
 
-            =====================================
-            """.stripIndent()
-        } else {
-            log.info """
-            ============================================\n
-            🎉 You earned extra raffle tickets! 🎉
-            ============================================
+        4. Run the pipeline with the additional configuration:
+        nextflow run seqeralabs/nf-raffle --email <your email> -c nextflow.config
 
-            Because you used Seqera Platform for this workflow,
-            you have received additional entries to the raffle.
+        =====================================
+        """.stripIndent()
+    } else {
+        log.info """
+        ============================================\n
+        🎉 You earned extra raffle tickets! 🎉
+        ============================================
 
-            Thank you for using Seqera Platform and good luck!
-            ============================================
-            """.stripIndent()
-        }
+        Because you used Seqera Platform for this workflow,
+        you have received additional entries to the raffle.
+
+        Thank you for using Seqera Platform and good luck!
+        ============================================
+        """.stripIndent()
+    }
+}
+
+output {
+    raffle_ticket {
+        path '.'
+        mode 'copy'
     }
 }
diff --git a/modules/local/congratulations/main.nf b/modules/local/congratulations/main.nf
@@ -1,12 +1,14 @@
+nextflow.enable.types = true
+
 process CONGRATULATIONS {
     tag "${congrats}"
     label 'process_single'
     container 'community.wave.seqera.io/library/sed_coreutils_procps-ng:749edc0a4a6c3ef9'
     conda "${moduleDir}/environment.yml"
 
     input:
-    path congrats
-    val next
+    congrats: Path
+    next: Boolean
 
     script:
     """

diff --git a/modules/local/enter_raffle/main.nf b/modules/local/enter_raffle/main.nf
@@ -1,23 +1,31 @@
+// This process stays untyped for output (workflow.sessionId/runName are unavailable
+// in typed processes). The onComplete block in main.nf also uses workflow.session.config.
+nextflow.enable.types = true
+
+include { EventConfig ; Participant } from '../../../types'
+
 process ENTER_RAFFLE {
-    tag "${email}"
+    tag "${participant.email}"
     label 'process_single'
     container 'community.wave.seqera.io/library/curl_util-linux_procps-ng:72cd763bb8c83eca'
     conda "${moduleDir}/environment.yml"
 
     input:
-    val next
-    val email
-    val affiliation
-    val first_name
-    val last_name
-    val config
+    participant: Participant
+    config: EventConfig
+    platform_enabled: Boolean
 
     output:
-    val workflow.sessionId, emit: session_id
-    val workflow.runName, emit: run_name
+    record(
+        session_id: workflow.sessionId.toString(),
+        run_name: workflow.runName,
+    )
 
     script:
-    def platform_enabled = workflow.session.config.navigate('tower.enabled') ?: false
+    def email = participant.email
+    def affiliation = participant.affiliation
+    def first_name = participant.first_name
+    def last_name = participant.last_name
     def destination = config.destination_url
     def form_fields = config.form_fields
 
@@ -26,20 +34,21 @@ process ENTER_RAFFLE {
     def workspace_id = System.getenv('TOWER_WORKSPACE_ID') ?: ''
     def platform_workflow_id = System.getenv('TOWER_WORKFLOW_ID') ?: ''
 
-    // Build curl data arguments - collect non-empty args into a list
-    def curl_args = []
-    if (form_fields.email) curl_args << "-d \"${form_fields.email}=${email}\""
-    if (form_fields.run_name) curl_args << "-d \"${form_fields.run_name}=${workflow.runName}\""
-    if (form_fields.hostname) curl_args << "-d \"${form_fields.hostname}=\$(hostname)\""
-    if (form_fields.uuid) curl_args << "-d \"${form_fields.uuid}=\$(uuidgen)\""
-    if (form_fields.platform_enabled) curl_args << "-d \"${form_fields.platform_enabled}=${platform_enabled}\""
-    if (form_fields.affiliation && affiliation) curl_args << "-d \"${form_fields.affiliation}=${affiliation}\""
-    if (form_fields.first_name && first_name) curl_args << "-d \"${form_fields.first_name}=${first_name}\""
-    if (form_fields.last_name && last_name) curl_args << "-d \"${form_fields.last_name}=${last_name}\""
-    if (form_fields.user_name) curl_args << "-d \"${form_fields.user_name}=${user_name}\""
-    if (form_fields.workspace_id) curl_args << "-d \"${form_fields.workspace_id}=${workspace_id}\""
-    if (form_fields.platform_workflow_id) curl_args << "-d \"${form_fields.platform_workflow_id}=${platform_workflow_id}\""
-    def curl_data = curl_args.join(' ')
+    // Built as immutable list (typed processes don't allow << or add)
+    def curl_args = [
+        form_fields.email ? "-d \"${form_fields.email}=${email}\"" : '',
+        form_fields.run_name ? "-d \"${form_fields.run_name}=${workflow.runName}\"" : '',
+        form_fields.hostname ? "-d \"${form_fields.hostname}=\$(hostname)\"" : '',
+        form_fields.uuid ? "-d \"${form_fields.uuid}=\$(uuidgen)\"" : '',
+        form_fields.platform_enabled ? "-d \"${form_fields.platform_enabled}=${platform_enabled}\"" : '',
+        form_fields.affiliation && affiliation ? "-d \"${form_fields.affiliation}=${affiliation}\"" : '',
+        form_fields.first_name && first_name ? "-d \"${form_fields.first_name}=${first_name}\"" : '',
+        form_fields.last_name && last_name ? "-d \"${form_fields.last_name}=${last_name}\"" : '',
+        form_fields.user_name ? "-d \"${form_fields.user_name}=${user_name}\"" : '',
+        form_fields.workspace_id ? "-d \"${form_fields.workspace_id}=${workspace_id}\"" : '',
+        form_fields.platform_workflow_id ? "-d \"${form_fields.platform_workflow_id}=${platform_workflow_id}\"" : '',
+    ]
+    def curl_data = curl_args.findAll { arg -> arg != '' }.join(' ')
 
     """
     curl -X POST ${curl_data} "${destination}"

diff --git a/modules/local/print_ascii_logo/main.nf b/modules/local/print_ascii_logo/main.nf
@@ -1,15 +1,17 @@
+nextflow.enable.types = true
+
 process PRINT_ASCII_LOGO {
     tag "${logo}"
     label 'process_single'
     container 'community.wave.seqera.io/library/sed_coreutils_procps-ng:749edc0a4a6c3ef9'
     conda "${moduleDir}/environment.yml"
 
     input:
-    path logo
-    val next
+    logo: Path
+    next: Boolean
 
     output:
-    val true
+    true
 
     script:
     """

diff --git a/modules/local/print_privacy_message/main.nf b/modules/local/print_privacy_message/main.nf
@@ -1,11 +1,12 @@
+nextflow.enable.types = true
+
+include { EventConfig } from '../../../types'
+
 process PRINT_PRIVACY_MESSAGE {
     label 'process_single'
 
     input:
-    val config
-
-    output:
-    val true
+    config: EventConfig
 
     exec:
     def winner_text = config.winner_announcement ? "\nWinner will be announced at ${config.winner_announcement}.\n" : ""
@@ -18,4 +19,8 @@ We respect your data. By submitting this form, you agree that we may use this
 information in accordance with our Privacy Policy (https://seqera.io/privacy-policy/).
 ${winner_text}""".stripIndent()
     )
+    ready = true
+
+    output:
+    ready
 }
diff --git a/modules/local/publish_report/main.nf b/modules/local/publish_report/main.nf
@@ -1,17 +1,18 @@
+nextflow.enable.types = true
+
 process PUBLISH_REPORT {
     tag "${event}: ${ticket_number}"
-    publishDir "${params.outdir}", mode: 'copy'
     container 'community.wave.seqera.io/library/sed_coreutils_procps-ng:749edc0a4a6c3ef9'
     conda "${moduleDir}/environment.yml"
 
     input:
-    path html_report
-    val event
-    val ticket_number
-    val winner_announcement
+    html_report: Path
+    event: String
+    ticket_number: String
+    winner_announcement: String
 
     output:
-    path "raffle_ticket.html"
+    file('raffle_ticket.html')
 
     script:
     def winner_text = winner_announcement ? "Winner announced ${winner_announcement}" : ""

diff --git a/nextflow.config b/nextflow.config
@@ -1,14 +1,13 @@
-params.help = false
-params.event = "eccb_2026"
-params.email = ""
-params.affiliation = ""
-params.first_name = ""
-params.last_name = ""
-params.outdir = "results"
-params.ticket_number_emit_session_id = false
+manifest {
+    nextflowVersion = '!>=26.04.0'
+}
+
+// Maps --outdir to the workflow output{} block. The params{} default in
+// main.nf is not visible here because the config is read before the script.
+outputDir = params.outdir ?: 'results'
 
 docker {
-    enabled = false
+    enabled    = false
     runOptions = '-u $(id -u):$(id -g)'
 }