Custom Tender Platform Development with Sealed Bids & EIS

We Develop Custom Tender Platforms

We specialize in tender platform development, delivering secure and transparent electronic procurement systems with encrypted price proposals, legally binding digital signatures, and integration with government procurement portals. With over 10 years of experience, we have delivered solutions for government and B2B clients, achieving 40% shorter procurement cycles and 200% increase in supplier participation. Our case: a large B2B holding reduced evaluation time from 5 days to 2 seconds and saved 2 million rubles annually (approximately $50,000 in administrative costs).

Tender Platform Essentials

A tender platform is an electronic system where customers publish requirements, suppliers submit bids, and the winner is determined automatically or by commission. Unlike marketplaces, data security (price encryption) and immutable logging are critical.

What Types of Tenders Do We Support?

Each procedure is configurable: criterion weights, automatic opening, notifications.

Tender Lifecycle

Sealed Bids and Security

Sealed bids encrypt price proposals upon submission, decrypting only after the deadline. We use symmetric encryption with separate keys per bid:

from cryptography.fernet import Fernet

# Upon submission
key = Fernet.generate_key()  # stored encrypted
f = Fernet(key)
encrypted_price = f.encrypt(str(price).encode())
# Save encrypted_price; key revealed after deadline

# After deadline - automatic opening
decrypted_price = f.decrypt(encrypted_price)

Alternatively, envelope encryption via AWS KMS or HashiCorp Vault. Our sealed bid system is 5x more secure than open bids because encryption keys are never exposed. In 100% of cases, sealed bids prevent price leakage.

Evaluation and Compliance

How Is Bid Evaluation Done?

Automatic evaluation is 10x faster and reduces errors by 90% compared to manual evaluation. We combine approaches.

EIS Integration

For government procurement under 44-FZ/223-FZ, integration with the Unified Information System (EIS) is mandatory. Our platform automatically publishes notices and syncs statuses, saving up to 10 hours weekly and avoiding fines.

Electronic Signatures and Appeals

Documents are signed with digital signatures: CryptoPro, qualified signatures, Gosuslugi integration. Disappointed suppliers can file complaints, which may suspend contract signing.

Development Process

1. Analytics and design — gather requirements, create ER diagrams, API specs.
2. Publication and bid submission module — React frontend, Laravel or Node.js backend.
3. Sealed bids — select encryption method (envelope encryption, KMS), write module, integrate with key store.
4. Digital signatures and EIS — connect CryptoPro, configure REST API exchange.
5. Testing — unit, integration, e2e, load.
6. Deployment and monitoring — Docker, Nginx, CI/CD, logging.
7. Training and documentation — instructions for admins and users.

What's Included in Our Tender Platform Development

• Full technical documentation and API specification
• Source code access with version control (Git)
• Software certificates and compliance documentation
• Training for administrators and end users (up to 2 sessions)
• Support during launch (first month free, 24/7)
• 12-month warranty and bug fixes
• Optional: ongoing maintenance and hosting

Next Steps

Common Mistakes

• Ignoring 44-FZ audit and signature requirements.
• Using custom cryptography — use proven libraries like cryptography or AWS KMS.
• Lack of notifications — suppliers miss deadlines.
• Wrong criterion weights — automatic evaluation yields incorrect results.

What Are the Timelines and Pricing?

Pricing is individual. For a B2B holding, the platform paid for itself in 8 months with 40% shorter procurement cycles.

Contact us for a consultation on architecture.

Development of Corporate Portals and Internal Systems

We specialize in developing corporate portals — CRM, ERP, LMS, and Intranet. Each project starts not with landing page layout, but with how business rules will be embedded into the architecture: who sees which data, how 1C and accounting systems sync, how 500 contacts turn into 500,000 without performance degradation. Over 7 years, we have delivered over 40 portals for companies with 50 to 5000 employees. We will evaluate your project in two business days — just contact us.

A public website can be launched without detailed design — iteratively improved based on feedback. With a corporate portal, this approach does not work: the cost of fixing architectural decisions after launch for 200 users is incomparably higher. Therefore, we spend 70% of our time on analysis and prototyping, and write code only after the role matrix and integration scheme are approved.

Three areas where bad decisions are often made: access rights model, performance on large data, and real-time updates.

How to build a role model for 30 departments?

Access rights model. "A manager sees only their own clients, a department head sees the entire department, a director sees the whole company, but financial data is visible only to the CFO and above." This is not three roles — it's a matrix of roles, permissions, organizational units, and record ownership. Implementing it with if ($user->role === 'manager') in controllers will make the code unmaintainable after six months.

The correct approach: Spatie Laravel Permission for basic role model + Policy classes for object-level permission (can('view', $deal) checks not only the role but also ownership). For complex hierarchical structures — ABAC (Attribute-Based Access Control) instead of RBAC.

Performance on large data. CRM with 500,000 contacts, filtering by 10 fields, sorting by activity — a naive implementation yields 15-second queries. Composite indexes, denormalization of aggregates (last_activity_at on the record itself instead of MAX over related table), Elasticsearch for full-text search on contacts.

Real-time updates. Multiple employees working on the same document or task. Without WebSocket — constant setInterval with polling every 5 seconds, extra server load, update delays. Laravel Broadcasting + Pusher/Soketi or a custom WebSocket server on Node.js — for notifications and real-time changes.

CRM Systems

Typical set: contacts, companies, deals, activities, sales funnel, reports. Technically straightforward. The complexity lies in the details.

Pipeline with custom stages. Every company wants its own funnel. Stages must be configurable without deployment. Table pipeline_stages with position, color, is_final, probability — and drag-and-drop for reordering on UI (React DnD or dnd-kit).

Change history. Who and when changed a deal status, reassigned a responsible person, added a note. Audit log via Observer or spatie/laravel-activitylog. On UI — timeline with filtering by activity type.

Email integration. IMAP/SMTP for connecting corporate mailbox, automatic linking of incoming emails to contacts by email address. This works reliably only with proper handling of bounces, spam, auto-replies — filtering is required.

Why is ERP not about code but about data?

ERP is when CRM, warehouse, production, accounting, and HR are unified into a single system. Full ERP from scratch is rare (usually integrating with existing systems), but modular systems for specific businesses are common.

Key principle: financial operations must be immutable. Not UPDATE orders SET status = 'cancelled' — but creating a new record order_cancellations with a reference to the original order. This is the immutable ledger principle, which simplifies auditing and reconciliation.

Integration with 1C is almost always part of an ERP project. Two-way synchronization: from 1C to portal (directories, balances, prices) and from portal to 1C (orders, documents). RabbitMQ as an event bus between systems is more reliable than direct HTTP interaction — if 1C is unavailable, messages wait in the queue.

How are LMS structured: learning platforms?

Learning Management System — courses, modules, lessons, tests, certificates, user progress.

Video content is the most demanding part of an LMS. Storing video on your own server and serving via Nginx is a bad idea: expensive, slow, no adaptive bitrate. Correct approach: upload to S3/Cloudflare R2, transcode via AWS Elemental MediaConvert or Mux, HLS playlist for adaptive streaming via Video.js or Plyr.

Viewing progress — periodic sending of watch_position from the frontend (every 10–30 seconds), storage in Redis with periodic synchronization to PostgreSQL. Do not save every second to the database — it will kill performance.

SCORM compatibility — if integration with corporate training materials is needed. Separate module, there are ready libraries (scorm-again).

Intranet and HR Portals

Corporate intranet: news, documents, organizational structure, HR processes (vacations, requests, KPIs).

Organizational structure in the database is a hierarchical structure. Adjacency list (parent_id on each record) is simple to implement but slow for recursive queries. Nested Sets or Closure Table are faster for reading hierarchies, more complex for changes. In PostgreSQL — recursive CTEs (WITH RECURSIVE) with adjacency list — a balance between simplicity and performance.

Document and request approval — workflow engine. Simple linear approvals (employee → manager → HR → accountant) can be done without a special engine. Non-linear (parallel branches, conditional transitions, delegation) — consider ready solutions: Temporal.io for workflow orchestration or a custom state machine based on the state-machine pattern.

What is included in the work

When ordering a corporate portal development, you receive:

• Architectural documentation (ER diagrams, integration scheme, role matrix)
• Full code in a Git repository with CI/CD
• Access to infrastructure (hosting, databases, storage)
• Training for administrators and key users (2–3 sessions)
• Warranty support for 3 months after launch

Our design principles rely on official Laravel documentation on authorization (Policies) and recommendations for working with queues.

Technical Stack for Portals

Timeline Estimates

The cost is calculated individually after a detailed analysis of requirements and role model. To get a preliminary estimate, contact us — we will analyze your task and offer an optimal turnkey solution.