Smart Contract Development
Solidity and Rust contracts written for auditability first, with full test coverage, upgrade strategy, and documented threat assumptions before anything touches mainnet.
010Full Stack Blockchain Development
Full Stack Blockchain Development Services
Webisoft builds complete blockchain products, from the smart contracts on chain to the web apps, APIs, and infrastructure around them. One senior Montreal team owns the entire stack so nothing falls between a contract shop and a frontend agency.
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What we build
Every layer of a production blockchain product
A token or protocol is not a product until users can actually reach it. We design and ship the full system: on-chain logic, off-chain services, and the interfaces that tie them together.
Web3 Frontends
React and Next.js applications with wallet connection, transaction signing, and clear state handling for pending, confirmed, and failed transactions.Backend and Indexing
APIs, event indexers, and databases that read chain state fast, so your app is not making users wait on RPC calls for every screen.Protocol Architecture
Token models, staking and vesting mechanics, and governance systems designed on paper and stress-tested in simulation before a line of contract code is written.Integrations and Bridges
Oracles, cross-chain messaging, fiat on-ramps, and exchange or custody integrations wired into your product with the failure modes handled.DevOps and Monitoring
Node infrastructure, CI pipelines with contract checks, and production monitoring that alerts you when on-chain behavior deviates from expected patterns.
How we work
From protocol design to mainnet
(4)- 1
Architecture and Threat Modeling
We map the full system, on chain and off, define trust boundaries, and decide what belongs in a contract versus a backend. This document becomes the contract for the build. - 2
Contracts First
Smart contracts are written, tested against forked mainnet state, and frozen for review early, because they are the hardest layer to change after launch. - 3
Application Build
Frontend, APIs, and indexing are built against the testnet deployment in parallel sprints, with weekly demos of working software rather than status decks. - 4
Audit, Launch, Operate
We support your external audit, remediate findings, run the mainnet deployment, and stay on for monitoring and iteration after launch.
Why Webisoft
One team accountable for the whole stack
Most blockchain projects fail at the seams, where the contract team's assumptions meet the app team's reality. We remove the seams.
Senior North American Engineers
Your product is built by experienced engineers in Montreal, not handed to a rotating bench. The people who scope the work write the code.Security as a Default
Test coverage requirements, forked-state testing, and audit preparation are part of every engagement, not a paid add-on you discover later.Product Thinking
We have shipped conventional software for years, so the wallet flows, error states, and onboarding get the same care as the contracts.Engineering Led
Scoping, estimates, and trade-off decisions come from the engineers building the system, which keeps timelines honest and architecture sound.
FAQ
Common questions about full stack blockchain builds
(4)- Cost is driven by smart contract complexity, the number of integrations, and audit scope. A focused MVP with a small contract surface and a web app is a materially smaller engagement than a multi-contract protocol with bridges and governance. Most teams scope the work in a fixed-price architecture phase first, which produces a concrete estimate before the full build is funded. Audit fees from independent firms are usually budgeted separately and can be significant for value-bearing contracts.
- The largest share of production work happens on EVM chains using Solidity, followed by Solana using Rust and the Anchor framework. The right choice depends on where the target users are, fee tolerance, and the ecosystem integrations the product needs, such as wallets, oracles, and liquidity. Choosing a chain based on user and cost data tends to produce better outcomes than following whichever ecosystem is loudest at the moment.
- Security review works best as an independent step. The development team prepares the codebase for audit with full test coverage and documentation, an external auditing firm performs the review, and the developers then remediate the findings. Having the same team both write and audit the contracts is a conflict of interest, so independent third-party audits are the standard practice for anything holding user funds. Clean, well-tested code going into audit keeps the process short and the findings minor.
- Yes, project takeovers are common in blockchain work. A takeover normally begins with a technical review of the contracts, infrastructure, and application code, followed by a written assessment of risks, gaps, and technical debt. From there the incoming team stabilizes the codebase and plans new work around what already exists. Handing over deployment access, documentation, and any prior audit reports makes the transition significantly faster.
Where we add value
One team across contracts, backend, and interface
Most blockchain projects stall in the gaps between specialists: a contract team that ships Solidity and leaves, a web team that has never handled a wallet. We build the whole stack as one system, so the product that launches is usable, indexed, and operable, not a proof of concept.
Smart contract engineering
We write contracts in Solidity for EVM chains and Rust for Solana and Cosmos targets, using audited building blocks like OpenZeppelin rather than novel code where a standard exists. Every contract ships with a full test suite in Foundry or Hardhat, documented upgrade strategy, and a threat model prepared before any external audit.Indexing and data infrastructure
Reading directly from a node is too slow and limited for real products. We build the indexing layer with subgraphs or custom indexers that stream chain events into PostgreSQL, giving your app fast queries, history, and analytics. This is the unglamorous piece that separates a working product from a demo.Wallets and user onboarding
We integrate wallet connections across MetaMask, WalletConnect, and Coinbase Wallet, and implement account abstraction or embedded wallets when your audience is not crypto native. Session handling, signature prompts, and transaction status feedback are designed deliberately, because clumsy wallet UX is the most common reason users abandon a dApp.Off-chain backend and hybrid logic
Real products keep most logic off-chain: user accounts, notifications, fiat payments, KYC flows, admin tools, and anything that must change faster than a contract can. We design the split between on-chain and off-chain deliberately, keeping on-chain what needs trust guarantees and off-chain what needs iteration speed and low cost.Security across the whole surface
Audits cover contracts, but exploits also come through frontends, signing flows, compromised keys, and oracle inputs. We handle the full surface: reentrancy and access control in contracts, transaction simulation before signing, key management for operational wallets, and monitoring that flags anomalous on-chain activity after launch.Tokenomics and mechanism review
Before we build, we pressure test the token or protocol design itself: incentive alignment, attack economics, regulatory exposure, and whether a token is even necessary for the product to work. Clients sometimes leave this review with a simpler design and a smaller contract surface, which means less to audit and less to defend.
Our approach
How a full stack blockchain build runs
(4)- 1
Protocol and product design
We start with a design phase that produces the protocol specification, the on-chain versus off-chain split, chain selection with reasoning, and the economic and threat models. This document becomes the reference for the build and the external audit, and it is where expensive mistakes are cheapest to fix. - 2
Contracts first, on testnet early
Smart contracts are built and tested first, with high branch coverage, fuzzing on state transitions, and invariant tests on the properties that must never break. We deploy to a public testnet within the first weeks so backend and frontend work proceeds against real chain behavior rather than mocks. - 3
Full product assembly
With contracts stable, we build the indexer, backend services, and interface in parallel, integrating continuously on testnet. Milestones are demoed as working software: connect a wallet, execute the core flow, see it reflected in the app. Audit preparation runs alongside, so the audit slot is booked before code freeze rather than discovered as a two month wait. - 4
Audit, mainnet, and operations
We support the external audit, remediate findings, and run the mainnet deployment with rehearsed scripts, verified contracts, and multisig or timelock controls on privileged functions. After launch we monitor contract activity and infrastructure, and hand over keys, documentation, and runbooks under an ownership structure you control.
FAQ
Questions buyers ask about full stack blockchain builds
(6)- The biggest variables are the novelty of the contract logic, the number of user facing flows, and the security bar you need to clear. A product assembled from proven standards like ERC-20 or ERC-721 with custom logic around them costs far less than a novel protocol design, because both engineering and audit scope shrink. External audits are a separate line item, typically tens of thousands of dollars depending on contract size and the firm. We give you the build and audit numbers separately so the total is visible up front.
- It depends on where your users and liquidity are, your fee tolerance, and your throughput needs. Ethereum mainnet suits high value, lower frequency transactions; L2s like Arbitrum and Base give EVM compatibility with much lower fees; Solana fits high frequency, low fee applications. Because we work across EVM and Solana, the recommendation follows your product economics rather than our stack preference, and we put the reasoning in writing so you can defend the choice to investors or partners.
- Audits from independent firms are a separate cost, and keeping them independent is the point. Our job is to make the audit cheap and fast: full test coverage, clean specifications, a threat model, and internal review before the auditors start, so they spend time on deep issues instead of basics. We book the audit slot early because good firms have long queues, then remediate findings and support the re-review. For lower budget launches, we help you weigh a smaller audit scope against contract simplification.
- Only if upgradeability is designed in, and that is a real trade-off. Proxy patterns let you upgrade logic but concentrate power in whoever holds the upgrade keys, which users and auditors scrutinize. We design the governance around upgrades explicitly: multisig ownership, timelocks so users can see changes coming, and immutability for components where trust matters most. The right answer differs between a DeFi protocol holding user funds and an internal enterprise chain application, and we set it per component rather than globally.
- We are engineers, not your law firm, but we build to the constraints your counsel sets and we know what those conversations involve. Practically that means KYC and sanctions screening integrations where required, geofencing, transaction monitoring hooks, and data handling that respects GDPR or Law 25 even when addresses are pseudonymous. Token design has securities law implications in most jurisdictions, so we encourage legal review during the design phase, when changing the mechanism is still cheap.
- Plan for three ongoing concerns: infrastructure like RPC nodes and indexers, key and multisig ceremony management, and monitoring of both contracts and services. We hand over infrastructure as code, runbooks, and access under your ownership, and we train your team on the operational rituals like signing procedures. Teams without in-house blockchain experience usually keep us on a retainer for operations and iteration; teams with engineers can take over fully, and the handover package is built for that.
