Every HR team on ERPNext eventually hits the same wall: HR Settings ships a single Offer Letter print format and a basic Appointment Letter, but the moment you need salary certificates for a bank, experience letters with tenure math, NOCs for travel, or Arabic-language contracts for a GCC labour office, you fall back to Word templates, manual copy-paste of employee data, and PDFs emailed around for wet signatures. Native ERPNext has no template library keyed to letter type, no merge engine beyond Jinja on a handful of DocTypes, no e-signature capture, and no way to track when a letter or its underlying document (visa, Emirates ID, contract) expires. The result is inconsistent documents, transcription errors in salaries and dates, and zero audit trail of who issued what.

We build a proper Frappe app — installed on your own bench as an app alongside erpnext and hrms — that adds a dedicated HR Letter Template DocType and an HR Letter transactional DocType. The template library ships pre-seeded with offer letter, employment contract, salary certificate, experience/service letter and NOC types, each holding a rich-text Jinja body so authorised users edit wording without touching code. When an HR admin creates an HR Letter, a whitelisted server method resolves the linked Employee and pulls the merge context — name, designation, department, date of joining, Salary Structure Assignment components, cost center, company details — and renders the template through Frappe's frappe.render_template, then generates a PDF via the standard print pipeline. Tenure and salary-in-words are computed server-side so the numbers are always correct and consistent.

The e-signature workflow is implemented as a Frappe Workflow on the HR Letter DocType (Draft → Pending Signature → Signed → Issued), with a client script rendering a signature-capture pad and storing the signed image plus signer identity, IP and timestamp in a child table for audit. A hooks.py on_submit doc event freezes the rendered PDF as an immutable attachment and, optionally, emails it to the employee. Bilingual output is handled by paired English/Arabic template bodies with RTL-aware print formats, so the same HR Letter can emit a bilingual document for GCC compliance. Document expiry and renewal are driven by a scheduler_events daily hook that scans expiry dates on letters and linked documents, raises ToDo/notification reminders at configurable lead times, and surfaces a renewals report. Everything respects ERPNext permissions — a dedicated HR Letters Manager role profile and DocType permissions ensure only entitled users issue letters, and the whitelisted methods are exposed on the Frappe REST API so an onboarding portal or third-party HR tool can request a letter programmatically.

Because this is build-to-order, nothing ships until we agree on scope. We start with a short scoping call to confirm your letter types, branding, bilingual requirements and approval chain, then build against Frappe/ERPNext v15 (with v16 compatibility), validate on a staging bench through UAT, and hand over installable source, a git repository and documentation. Typical delivery is 2-4 weeks from confirmed scope — no marketplace download, no fabricated "one-click" promise, just a maintained app installed on your bench with a post-go-live support window.