The 2025 Mid-Market HR Tech Stack Guide: Architecture Decisions That Actually Matter

PeopleOps Journal | December 2025

The Uncomfortable Truth About HR Tech Stacks

Here's what most HR tech guides won't tell you: the vendors you're evaluating are increasingly trying to eat each other's lunch, and the "best of breed vs. suite" framing that dominated the last decade is now almost useless.

Rippling added an ATS. Deel launched a free HRIS and acquired a performance management platform. Lattice built an HRIS (then killed it). Ashby keeps expanding beyond applicant tracking. The category boundaries that made stack decisions straightforward in 2020 have dissolved into a messy competitive free-for-all.

For mid-market HR teams—those managing 100 to 500 employees with maybe two to four people in the function—this creates a genuine strategic problem. You can't evaluate tools in isolation anymore. Every vendor selection is now a bet on which company will successfully expand into adjacent territory and which will retreat to their core.

This guide is built around that reality. We're not going to walk you through feature checklists. Instead, we'll map the actual architecture decisions you face, where the competitive overlaps create real tension, and how to think about building a stack that won't require painful migrations in 18 months.

The Five Layers of a Modern HR Stack

Before diving into vendor specifics, it helps to understand what you're actually building. A functional mid-market HR tech stack has five distinct layers, and the strategic question is how many vendors you want touching each one:

Layer 1: System of Record (Employee Data) Where employee information lives as the canonical source. Every other system pulls from or pushes to this layer.

Layer 2: Compensation & Payroll Infrastructure How people get paid, including salary benchmarking, payroll processing, and equity administration.

Layer 3: Talent Acquisition How candidates become employees—sourcing, tracking, scheduling, and hiring decisions.

Layer 4: Performance & Development How you measure contribution, facilitate feedback, and develop people over time.

Layer 5: Engagement & Culture Measurement How you understand what employees actually think and whether your culture matches your intentions.

The architectural question isn't "which tool is best for each layer" but rather "how many layers should a single vendor own?"

The Three Viable Architectures for 2025

Based on how the vendor landscape has evolved, mid-market companies now face three realistic architectural patterns. Each has genuine trade-offs that depend on your specific situation.

Architecture A: The Rippling Maximalist Approach

What it looks like: Rippling as your foundation across Layers 1, 2, and potentially reaching into 3, 4, and 5 through its expanding module set.

The case for it: If you're a 150-person company with a two-person HR team, consolidation isn't a luxury—it's survival. Rippling's core value proposition is that one system handles employee records, payroll, benefits, device management, and increasingly, recruiting and performance. The automation that flows from unified data is real: onboarding that provisions laptops, creates accounts, enrolls benefits, and sets up payroll from a single action genuinely saves hours per hire.

The IT integration angle is underappreciated. Most HR platforms treat device management and SSO as someone else's problem. Rippling treats them as fundamentally connected to employee lifecycle management—because they are. For companies with significant SaaS sprawl (and which mid-market tech company doesn't have this?), that connection matters.

The honest trade-off: Rippling's expanding modules are good enough for most use cases but rarely best-in-class. Their ATS won't match Ashby's depth. Their performance tools won't match Lattice's sophistication. Their engagement features won't match Culture Amp's research foundation. You're trading specialized capability for operational simplicity.

Who should consider this: Companies where HR headcount is genuinely constrained, where IT and HR coordination is a real pain point, and where "good enough across everything" beats "excellent in one area, chaotic in others."

Architecture B: The Specialized Layer Cake

What it looks like: A core HRIS (Rippling, BambooHR, or similar) handling Layer 1, with purpose-built tools at each additional layer: Ashby for recruiting, Lattice or Culture Amp for performance and engagement, Pave for compensation intelligence.

The case for it: Specialized tools exist because generalist platforms make real compromises. Ashby's recruiting analytics let talent teams understand pipeline velocity, source quality, and conversion patterns in ways that bolted-on ATS modules simply don't support. Lattice's integration of goals, feedback, reviews, and engagement data creates a performance picture that standalone review tools can't match. Pave's real-time compensation benchmarking—refreshed continuously through HRIS integrations rather than annual surveys—enables pay decisions that static data can't support.

When you're competing for talent against companies with dedicated recruiting ops, compensation analysts, and people analytics teams, specialized tools help level the playing field. You're essentially buying capabilities you can't afford to build internally.

The honest trade-off: Integration is the tax you pay for specialization. Even with modern APIs and pre-built connectors, data synchronization between five or six systems requires ongoing attention. Employee records need to flow correctly. Organizational changes need to propagate. Someone on your team needs to own the plumbing, and when things break—and they will occasionally break—you're troubleshooting across multiple vendor support queues.

The cost math also compounds. Rippling at $25-35 per employee per month covers a lot of ground. Add Ashby, Lattice, Pave, and you're potentially looking at $50-60 per employee monthly across your stack. For a 300-person company, that's the difference between $90K and $180K annually in HR tech spend.

Who should consider this: Companies with at least one person who can own HR systems administration, where specific functional excellence (particularly in recruiting or performance) is a competitive differentiator, and where the budget supports premium tooling.

Architecture C: The Global-First Stack

What it looks like: Deel as the foundation for international employment, potentially as the HRIS even for domestic employees, with specialized tools layered on top for recruiting and performance.

The case for it: If you're hiring across borders—and increasingly, mid-market companies are—the traditional architecture inverts. Your primary constraint isn't which HRIS has the best onboarding workflow; it's which platform can legally employ someone in Portugal, process payroll in Singapore, and ensure compliance in Brazil without you becoming an expert in three countries' labor law.

Deel's Employer of Record model handles this complexity by serving as the legal employer in 150+ countries through owned entities. For companies that went from "occasional international hire" to "20% of our workforce is outside the US" over the past three years, this isn't a nice-to-have—it's the only viable path that doesn't require building an international HR function from scratch.

The 2025 addition of free HRIS functionality changes the calculus further. If you're using Deel for international payroll anyway, consolidating domestic employee records there eliminates one integration point and one vendor relationship. Add the acquired Zavvy platform for performance management, and you're approaching Rippling-style consolidation but with global employment as the foundation rather than US-centric HR.

The honest trade-off: Deel's HRIS and performance modules are newer and less mature than established players. If your workforce is 90% US-based with occasional international contractors, you're paying an architectural tax for global capabilities you rarely use. The $599 per employee per month for EOR is also dramatically more expensive than domestic payroll—justified when you're avoiding entity setup costs and compliance risk, but worth scrutinizing if you're at scale in specific countries where your own entity might make sense.

Who should consider this: Companies where international hiring is a consistent need (not just occasional), where the HR team lacks international employment expertise, and where speed to hire globally matters more than optimizing domestic HR workflows.

The Overlap Zones: Where Vendors Compete Directly

Here's where stack decisions get genuinely complicated. These aren't complementary tools occupying different layers—they're direct competitors for the same budget.

Recruiting: Rippling vs. Ashby

Rippling's ATS checks the basic boxes: job postings, candidate tracking, interview scheduling, offer management. For companies making 20-30 hires per year with straightforward processes, it's sufficient and eliminates one integration.

Ashby is built for companies that treat recruiting as a strategic function. The analytics depth—understanding which sources produce candidates who actually succeed, where your pipeline bottlenecks, how interview load distributes across your team—creates visibility that Rippling's module doesn't approach. The automation capabilities (one customer reported 80% of onboarding tasks automated) and the AI-assisted features (natural language candidate search, automated outreach personalization) reflect a platform built by people who think about recruiting all day.

Decision framework: If recruiting is a core competency for your company—if hiring velocity and quality directly drive business outcomes—Ashby justifies its cost and integration overhead. If recruiting is important but not differentiating, Rippling's module is good enough and you're better off investing your HR tech budget elsewhere.

Performance & Engagement: Lattice vs. Culture Amp vs. Rippling vs. Deel

This is the messiest competitive overlap in the stack.

Lattice combines performance management (reviews, goals, feedback) with engagement measurement in a genuinely integrated way. A manager can see how their team's engagement scores correlate with performance outcomes. The AI-assisted review writing reportedly cuts review drafting time in half. The emphasis on continuous feedback—weekly check-ins, real-time recognition—positions formal reviews as summaries rather than surprises.

Culture Amp leads with research credibility. Questions are validated by organizational psychologists. Recommendations tie to evidence about what actually moves engagement scores. For HR leaders who need to make the case to skeptical executives, that research foundation provides ammunition that "we surveyed people and here's what they said" doesn't.

Rippling's performance and survey tools exist but are clearly younger. They work for basic needs but lack the sophistication of dedicated platforms.

Deel's acquired Zavvy platform (now Deel Engage) adds performance, goals, and learning to their global employment foundation. It's too early to evaluate how well this integrates and whether it approaches Lattice or Culture Amp capability.

Decision framework: If you're choosing between Lattice and Culture Amp, the honest answer is that both are strong and your decision might come down to which demo resonates more with your team. Lattice slightly edges toward performance management sophistication; Culture Amp slightly edges toward engagement measurement depth. If you're trying to decide whether you need either one versus using Rippling's built-in tools, the question is whether performance and engagement are strategic priorities worth dedicated investment or functional requirements you just need to check off.

Compensation: Pave vs. Everyone Else

Pave occupies a somewhat unique position. Rippling doesn't offer comparable compensation benchmarking intelligence. Deel doesn't either. Neither does Lattice or Culture Amp. For real-time market data on what companies are actually paying—not what they reported in a survey 18 months ago—Pave is effectively the only mid-market-accessible option with this specific capability.

The question isn't "Pave vs. competitor X" but rather "do we need dedicated compensation intelligence at all?" If you're making fewer than 30 offers a year and compensation isn't a regular competitive disadvantage, annual survey data might be sufficient. If you're hiring continuously in competitive markets and regularly losing candidates to compensation gaps, Pave's real-time benchmarking pays for itself in prevented mis-hires.

The total rewards portal—helping employees understand the full value of their compensation package—addresses a different problem: the perception gap where employees undervalue what they receive because equity, benefits, and other components aren't clearly communicated. Whether that problem is acute for your company depends on your workforce composition and whether retention is a live issue.

Integration Reality: What The Vendors Won't Emphasize

Every platform claims robust integrations. Here's what actually matters:

Depth of data sync matters more than breadth of connectors. Having a "Greenhouse integration" means little if it only syncs candidate names and emails rather than full application data, interview feedback, and offer details. Before committing, verify exactly what data flows between systems you plan to connect.

Bidirectional sync is harder than it sounds. Most integrations are one-way: data flows from System A to System B. When you need changes in either system to reflect in the other—employee title changes that should update access permissions, for instance—confirm that the integration supports this rather than requiring manual reconciliation.

Someone needs to own the plumbing. If you're running five systems, you need someone on your team who understands how data flows between them, monitors for sync failures, and troubleshoots when things break. For a two-person HR team, this overhead might be the deciding factor toward consolidation even if you'd prefer specialized tools.

Rippling's integration advantage is real but not absolute. The 600+ integrations and the workflow automation that spans across modules is a genuine differentiator. But "integration exists" and "integration works exactly as you need" aren't always the same thing. Several reviewers have noted difficulties syncing Rippling with specific accounting systems beyond basic fields.

The Build Sequence: What Order To Implement

If you're building or rebuilding your stack, sequencing matters:

Phase 1: Nail your system of record first. Everything else depends on clean employee data. Whether that's Rippling, Deel, BambooHR, or another HRIS, get this stable before adding layers. Migrating your core employee database is disruptive; you want to do it once.

Phase 2: Solve your most acute pain point second. If hiring is your bottleneck, implement Ashby before worrying about performance management. If engagement measurement is your blind spot, Culture Amp before compensation intelligence. Don't try to implement everything simultaneously—it overwhelms your team and extends time-to-value for everything.

Phase 3: Add capabilities as you actually need them. Pave is powerful, but if you're making 15 hires a year, you might not need real-time benchmarking yet. Deel's EOR is essential if you're hiring internationally, unnecessary if you're not. Buy tools for the problems you have today, not the problems you might have in two years.

What's Coming: 2026 Trends Worth Watching

Three developments will reshape these decisions over the next 12-18 months:

The AI capability gap will widen. Ashby, Lattice, and Culture Amp are investing heavily in AI features—natural language querying, automated feedback drafting, theme extraction from survey responses. Platforms that underinvest here will feel increasingly dated. Watch which vendors ship AI capabilities that actually save time versus which ship AI marketing copy.

Rippling and Deel will collide more directly. Both are expanding toward "unified workforce platform for global companies." Rippling is adding international capabilities; Deel is adding domestic HR sophistication. Within two years, they'll be much more directly competitive than they are today. If you're choosing between them, you're partly betting on which company executes better on their expansion roadmap.

The HRIS layer will commoditize further. Deel offering free HRIS is the most aggressive move, but it signals a broader trend: basic employee record-keeping is becoming table stakes rather than a revenue driver. Expect more vendors to use HRIS as a wedge for higher-value products, which benefits buyers but also creates pressure to upsell.

The Stack Configurations That Actually Work

For mid-market HR leaders who want concrete recommendations rather than frameworks:

The "Lean Team, Maximum Automation" Stack: Rippling (full platform) + keep your existing best-of-breed tool if you have one that's working

This works when you have fewer than three people in HR, when IT coordination is a real problem, and when operational simplicity trumps functional perfection.

The "Recruiting-Centric" Stack: HRIS of choice + Ashby + lightweight performance management (possibly Lattice Grow or built-in HRIS features)

This works when hiring volume and quality are your primary competitive battleground.

The "Culture-Forward" Stack: HRIS of choice + Lattice or Culture Amp + Pave (if competing for talent in hot markets)

This works when retention is a primary concern, when leadership has bought into people development as strategy, and when you have bandwidth to actually act on engagement data.

The "Global-First" Stack: Deel (EOR + HRIS + Engage) + Ashby (if recruiting volume warrants)

This works when international employment is a consistent need and when you want one vendor relationship for global workforce complexity.

Final Thought: The Best Stack Is the One You Actually Use

The HR tech industry generates endless content about features, integrations, and capabilities. What gets less attention is the activation reality: most companies use 40-60% of the features they pay for. The unused capabilities are pure cost.

The right stack isn't the one with the most impressive feature list. It's the one your team will actually learn deeply, configure properly, and use to drive better outcomes. A well-implemented Rippling deployment that automates everything possible beats a theoretically superior five-tool stack where each system is partially configured and nobody owns the integration layer.

Start with the problem you're solving and the capacity you have to implement solutions. The vendors will always be there selling more.

This guide was produced by PeopleOps Journal's research team based on vendor research briefs, customer reviews, and analyst conversations. Our analysis reflects genuine assessment, but readers should conduct their own evaluation for their specific contexts.

That's roughly 3,000 words. Want me to adjust the length, add specific sections (like a comparison table that doesn't feel too generic), or shift the emphasis anywhere?