Build vs Buy: Should You Build Your Own Contract Tool?

"Build vs buy" for contract management usually means one of three things: a spreadsheet tracking contract status with files in a shared drive, an internal tool a company's own engineers write, or a workflow someone stitches together by calling an AI API directly. All three are "build." Buying means a subscription to software someone else maintains, Adira among the options, worth stating plainly here: Adira, which publishes this guide, sells the buy-side option, and this comparison is written to hold up even if build is right for you. The honest short answer is that most small teams underestimate what build costs once security, e-signature, and evidence requirements are counted in, and a smaller number of large teams with unusual workflows are right to build anyway. What follows is what changes that answer, and where.

What "build" actually looks like

The three versions of build are not equally serious commitments.

A spreadsheet and shared drive costs nothing to start and needs no engineering time. It has no obligation logic (nothing reminds you a renewal notice period has started), no version control beyond filenames, and no audit trail of who changed what. It works for low volume because a person can hold the whole picture in their head.

An internal app is a real engineering project: a database of contracts, a review workflow, some notion of status and approvals. It costs real developer time to build and, more importantly, real developer time forever afterward, because a system that stops getting maintained quietly becomes a liability.

An AI API wrapper is the newest version: a team calls a large language model's API to draft or review clauses and writes a thin interface around it. Fast to prototype, sometimes a weekend's work, but the model call is a small fraction of what a contract tool does. Drafting or flagging a clause is not tracking who signed what, when a renewal notice is due, or what happens when a dispute lands three years later and someone asks for the record.

Who should even be weighing this decision

Below roughly ten contracts a month, with one or two people involved, the decision barely matters: a disciplined spreadsheet and drive, formalised with a simple playbook, is fine, and buying is premature. Between ten and a hundred, or once more than a couple of people approve or negotiate, gaps in a spreadsheet start costing real time and risk, and this is the band where the decision is live. Past a hundred a month, most teams have already decided, and the question is whether that was deliberate or by default.

The real cost of building it yourself

Engineering time you did not budget for

A workable first version, review workflow, status tracking, basic e-signature, reminders, is realistically a few engineer-months, not a weekend, even for a team honest about scope. The bigger cost comes after: a tool touching money, deadlines, and personal data cannot be left alone the way an internal dashboard can. Teams usually underweight the ongoing share, ballpark a fifth to a third of one engineer's time indefinitely, for a system that is not the company's core product and always competes for attention with things that are.

Security and DPDP compliance land on you either way

Section 8(5) of the Digital Personal Data Protection Act, 2023 states:

"A Data Fiduciary shall protect personal data in its possession or under its control, including in respect of any processing undertaken by it or on its behalf by a Data Processor, by taking reasonable security safeguards to prevent personal data breach."

Read the section on Indian Kanoon. A contract is full of personal data: counterparty names, signatory emails, salary figures in an offer letter, bank details in a vendor form. You are the Data Fiduciary the moment you process that data, whether the tool is a spreadsheet you built or a vendor's platform you pay for. Building means implementing encryption, access controls, and breach-detection logging yourself, with no vendor security team behind you. Buying does not remove the obligation, Section 8 keeps it with you regardless of who wrote the software, but a vendor's existing controls and terms do part of the work a build would otherwise leave entirely to your own team.

E-signature integration is not "add an API"

Section 5 of the Information Technology Act, 2000 gives electronic signatures legal recognition:

"Where any law provides that information or any other matter shall be authenticated by affixing the signature or any document shall be signed or bear the signature of any person, then, notwithstanding anything contained in such law, such requirement shall be deemed to have been satisfied, if such information or matter is authenticated by means of electronic signature affixed in such manner as may be prescribed by the Central Government."

Read it on Indian Kanoon. Two things follow that a build project usually discovers late. First, the Act's First Schedule excludes some documents from electronic execution altogether: negotiable instruments other than cheques, powers of attorney, trusts, wills, and contracts for sale or transfer of immovable property, so no build or buy tool can e-sign these, they still need a wet signature. Second, for everything else, an e-signature's legal strength depends on it being "in such manner as may be prescribed," which in practice means a licensed Certifying Authority or Aadhaar eSign, not a homegrown "type your name in a box" flow. Building a compliant e-signature experience almost always means integrating a licensed provider anyway, so build is not avoiding a vendor here, it is adding an integration project instead of buying a finished one.

Evidence in a dispute depends on more than a saved PDF

Section 63 of the Bharatiya Sakshya Adhiniyam, 2023, which replaced Section 65B of the Indian Evidence Act, 1872 from 1 July 2024, sets the rule for using an electronic record as evidence: computer output is admissible without the original being produced, but only with a certificate identifying the record, describing the device and process that produced it, and confirming the conditions of reliable production, signed by someone responsible for that device. Read the section on Indian Kanoon. The Supreme Court had already made the certificate mandatory under the old Section 65B in Arjun Panditrao Khotkar v Kailash Kushanrao Gorantyal (Supreme Court, judgment dated 14 July 2020), holding that no electronic record can be admitted as secondary evidence without it, overruling contrary views that had allowed oral testimony to substitute. A spreadsheet-and-drive setup, or a homemade app built without this in mind, usually cannot produce those elements years later: nobody logged the device, nobody kept a hash at signature, nobody was assigned to confirm the conditions. That gap becomes visible the day a dispute starts, exactly the day it is too late to fix.

Obligation logic and the long tail

Reminder logic looks simple for one contract type and one renewal date. It stops being simple once obligations span payment milestones, notice periods measured from delivery rather than signature, amendments that shift a renewal date without anyone updating the master record, and escalation rules for who gets notified when a deadline is missed. This is the part of build that grows fastest and shows up last, because the first ten contracts never expose it.

The real cost of buying

Buying trades a large uncertain cost for a smaller predictable one, but not free of trade-offs. A subscription is a recurring cost that scales with seats or volume. Customisation is bounded by what the vendor supports, so an unusual workflow may not fit cleanly. Switching vendors later means migrating data and rebuilding templates, a real cost easy to ignore at signup. And buying does not remove your legal responsibility: under Section 8 you remain the Data Fiduciary, so a buyer still needs to review the vendor's data processing terms rather than assume the fee covers compliance by itself.

Red flags, either way

Normal	Red flag	Why it matters
Build estimate includes ongoing maintenance	"Quick MVP" estimate, no maintenance line	A tool touching personal data and money degrades quietly without upkeep, until a dispute exposes the gap
Spreadsheet and drive used only below a stated volume threshold	Kept indefinitely because "it still technically works"	It works until a reminder doesn't fire, or a version gets overwritten, and by then the damage is done
E-signature runs through a licensed Certifying Authority or Aadhaar eSign	An in-house "type your name to agree" checkbox	A weak signature process undermines the legal recognition Section 5 is meant to give it
A named person owns DPDP compliance, build or buy	Nobody owns it, "the vendor handles it" or "we built it so it's ours"	Section 8 obligations sit with the Data Fiduciary either way; the tool does not absorb the responsibility
Vendor's data processing terms reviewed before signing	Vendor chosen on price and features, terms never read	Without reviewing those terms you cannot show reasonable steps under Section 8(5)
Build has a documented owner and a handover plan	One engineer wrote it, and nobody else can maintain it	A tool only one person can touch becomes a real liability once the company depends on it
Export and migration terms agreed before signing	No stated way to get data out if you switch vendors	Lock-in turns a subscription into a multi-year commitment nobody consciously chose

A record-keeping clause written badly, and well

Most build projects skip writing down how contract records will be kept in a way that survives a Section 63 certificate request years later. Here is the same clause, from an internal execution policy, written badly and then well.

Bad version, written in five minutes and never revisited:

"All contracts will be signed electronically and stored in the company drive."

This says nothing about the e-signature method used, whether it meets the "under sole control" standard, or what technical detail would exist if a Section 63 certificate were ever needed.

Better version, naming the specifics a court would actually ask for:

"All contracts are executed through [named e-signature provider], which records signer identity verification, IP address, timestamp, and a document hash for each signature. Executed documents and their metadata are retained for [stated period] in a system that preserves the original file, the device and process details needed to produce a certificate under Section 63 of the Bharatiya Sakshya Adhiniyam, 2023, and a log of any edits made after execution."

What changed: it names a specific, auditable signature channel instead of "electronically," states a retention period, and calls out the exact details Section 63(4) asks a certificate to cover. That is what turns "we have a saved PDF" into a record a court can use.

A decision framework, by team size, volume, and engineering capacity

Under ten contracts a month, with no dedicated engineers, a spreadsheet and shared drive, run against a written playbook, is right. Buying is premature; testing whether AI-assisted review helps at all is cheaper first, and you can mark up a contract clause by clause for free in Weave, Adira's free browser-based tool, with no account needed.

In the ten-to-hundred range, with no dedicated engineering team, buying is almost always right. This is the band where the real cost of build, security controls, a properly integrated e-signature provider, obligation logic that keeps working as contracts get complex, and records that would survive a Section 63 certificate request, consistently outweighs a subscription, and where a homegrown app becomes the single-point-of-failure risk flagged above.

Past a hundred contracts a month, with real in-house engineering capacity and a genuinely unusual workflow, for example contracts generated programmatically inside another product, build can be right. These cases are a minority, sharing two traits: a workflow that does not resemble a normal contract lifecycle, and an engineering team that would maintain the system anyway as part of the core product. Even then, budget for what it includes: security controls meeting Section 8(5), a signature integration that still means paying a licensed Certifying Authority, obligation logic maintained as a real product with an owner, and a records policy that would hold up years later. Teams that price all of that in, and still find it cheaper at their scale, are the correct build cases. Teams that stop at "we'll wire up an API this weekend" have not weighed the same decision at all.

Where to go next

If buying looks right, How to Choose a CLM: A Buyer's Checklist covers evaluating vendors. If volume is still small enough that neither build nor a paid platform is clearly worth it yet, Free CLM Alternatives for Small Teams covers lightweight options to run meanwhile.

US and global contrast

US federal law recognises electronic signatures through the ESIGN Act and, at state level, the Uniform Electronic Transactions Act, on a similar functional-equivalence idea to Section 5: a signature counts if the parties intended it to. But US evidence rules carry no direct equivalent to the Section 63 certificate; admissibility runs through the Federal Rules of Evidence's authentication provisions, more flexible than India's certificate-or-original rule. On data protection, the US has no single federal law resembling the DPDP Act; obligations vary by state and sector. A US-origin checklist that assumes "we captured an e-signature" is enough, or that data protection is one settled standard, misses both the certificate requirement and the data fiduciary obligations that apply in India regardless of where the software was built.

FAQ

Is a spreadsheet and shared drive good enough to start? Yes, for low volume with one or two people involved. It stops being enough once obligation tracking, multiple approvers, or dispute-ready evidence become real requirements.

What does something built in-house need at minimum to be DPDP-compliant? Reasonable security safeguards under Section 8(5), encryption and access controls at a minimum, a named owner for that compliance, and equivalent safeguards required by contract if any processing is outsourced. None of this is optional just because the tool is homegrown.

Can we just wire up an LLM API and call that our CLM? That covers drafting and review assistance, a real part of the job, but not obligation tracking, signature evidence, or records that survive a dispute years later. Most teams trying this end up building the rest of a CLM around the API call anyway, which is the actual cost.

Does buying a CLM remove our DPDP obligations? No. Section 8 keeps the Data Fiduciary's obligations with your company regardless of who built the software. Buying can make meeting them easier if the vendor's controls and terms are solid, but it does not transfer the legal responsibility away from you.

What is the biggest cost teams miss when they decide to build? The certificate-ready evidence trail under Section 63 of the Bharatiya Sakshya Adhiniyam. Teams budget for drafting and storage, then discover during an actual dispute that nobody logged the device, hash, or process details a certificate needs.

Is Weave a build or a buy option? Neither. It is a free tool for marking up and reviewing a contract clause by clause in the browser, useful for testing whether AI-assisted review helps at all before committing engineering time or a subscription budget.

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This guide explains what build costs against what buying costs, and where DPDP security obligations, e-signature validity, and evidence certificates land on each path. It does not tell you whether your team's workflow, volume, or engineering capacity makes build or buy correct for you, or whether a build already underway meets the legal requirements described here. For that, before committing engineering time to an in-house tool or signing a multi-year vendor contract, get someone who has reviewed your actual setup, a lawyer for the compliance and evidence questions, an engineer for the build estimate, to look at it directly. This is not legal advice.